diff --git a/app/scripts/abi.sh b/app/scripts/abi.sh
index 4a92977c63..824915972f 100644
--- a/app/scripts/abi.sh
+++ b/app/scripts/abi.sh
@@ -8,10 +8,10 @@ nix build .#evm-contracts --print-build-logs
 
 IBC_HANDLER=$(jq --slurp 'map(.abi) | add' \
     result/out/IBCClient.sol/IBCClient.json \
-    result/out/IBCPacket.sol/IBCPacket.json \
-    result/out/IBCConnection.sol/IBCConnection.json \
+    result/out/IBCPacket.sol/IBCPacketImpl.json \
+    result/out/IBCConnection.sol/IBCConnectionImpl.json \
     result/out/OwnableIBCHandler.sol/OwnableIBCHandler.json \
-    result/out/IBCChannelHandshake.sol/IBCChannelHandshake.json)
+    result/out/IBCChannel.sol/IBCChannelImpl.json)
 
 echo "export const ibcHandlerAbi = <const>${IBC_HANDLER}" >| app/src/lib/abi/ibc-handler.ts
 
diff --git a/evm/ARCHITECTURE.md b/evm/ARCHITECTURE.md
index 7d4e05e4d8..5b6373f6a9 100644
--- a/evm/ARCHITECTURE.md
+++ b/evm/ARCHITECTURE.md
@@ -67,7 +67,7 @@ sequenceDiagram
 
 ```
 
-To relax the contract size limit of ethereum, each ICS implementation is split into [IBCClient](contracts/core/02-client/IBCClient.sol), [IBCConnection](contracts/core/03-connection/IBCConnection.sol), [IBCChannel](contracts/core/04-channel/IBCChannelHandshake.sol), [IBCPacket](contracts/core/04-channel/IBCPacket.sol), and [IBCHandler](contracts/core/25-handler/IBCHandler.sol) contracts, as shown in the above figure.
+To relax the contract size limit of ethereum, each ICS implementation is split into [IBCClient](contracts/core/02-client/IBCClient.sol), [IBCConnection](contracts/core/03-connection/IBCConnection.sol), [IBCChannel](contracts/core/04-channel/IBCChannel.sol), [IBCPacket](contracts/core/04-channel/IBCPacket.sol), and [IBCHandler](contracts/core/25-handler/IBCHandler.sol) contracts, as shown in the above figure.
 
 In general, such a design causes storage splitting, so it is required to implement unnecessary authentication and accessors for inter-contract calls.
 
diff --git a/evm/contracts/apps/Base.sol b/evm/contracts/apps/Base.sol
index 71a2fbbc27..38eebde07f 100644
--- a/evm/contracts/apps/Base.sol
+++ b/evm/contracts/apps/Base.sol
@@ -38,12 +38,11 @@ abstract contract IBCAppBase is IIBCModule {
      * NOTE: You should apply an `onlyIBC` modifier to the function if a derived contract overrides it.
      */
     function onChanOpenInit(
-        IbcCoreChannelV1GlobalEnums.Order,
-        string[] calldata connectionHops,
-        string calldata portId,
-        string calldata channelId,
-        IbcCoreChannelV1Counterparty.Data calldata counterpartyEndpoint,
-        string calldata version,
+        IBCChannelOrder ordering,
+        uint32 connectionId,
+        uint32 channelId,
+        IBCChannelCounterparty calldata counterpartyEndpoint,
+        bytes32 version,
         address relayer
     ) external virtual override onlyIBC {}
 
@@ -53,13 +52,12 @@ abstract contract IBCAppBase is IIBCModule {
      * NOTE: You should apply an `onlyIBC` modifier to the function if a derived contract overrides it.
      */
     function onChanOpenTry(
-        IbcCoreChannelV1GlobalEnums.Order,
-        string[] calldata connectionHops,
-        string calldata portId,
-        string calldata channelId,
-        IbcCoreChannelV1Counterparty.Data calldata counterpartyEndpoint,
-        string calldata version,
-        string calldata counterpartyVersion,
+        IBCChannelOrder ordering,
+        uint32 connectionId,
+        uint32 channelId,
+        IBCChannelCounterparty calldata counterpartyEndpoint,
+        bytes32 version,
+        bytes32 counterpartyVersion,
         address relayer
     ) external virtual override onlyIBC {}
 
@@ -69,10 +67,9 @@ abstract contract IBCAppBase is IIBCModule {
      * NOTE: You should apply an `onlyIBC` modifier to the function if a derived contract overrides it.
      */
     function onChanOpenAck(
-        string calldata portId,
-        string calldata channelId,
-        string calldata counterpartyChannelId,
-        string calldata counterpartyVersion,
+        uint32 channelId,
+        uint32 counterpartyChannelId,
+        bytes32 counterpartyVersion,
         address relayer
     ) external virtual override onlyIBC {}
 
@@ -82,8 +79,7 @@ abstract contract IBCAppBase is IIBCModule {
      * NOTE: You should apply an `onlyIBC` modifier to the function if a derived contract overrides it.
      */
     function onChanOpenConfirm(
-        string calldata portId,
-        string calldata channelId,
+        uint32 channelId,
         address relayer
     ) external virtual override onlyIBC {}
 
@@ -93,8 +89,7 @@ abstract contract IBCAppBase is IIBCModule {
      * NOTE: You should apply an `onlyIBC` modifier to the function if a derived contract overrides it.
      */
     function onChanCloseInit(
-        string calldata portId,
-        string calldata channelId,
+        uint32 channelId,
         address relayer
     ) external virtual override onlyIBC {}
 
@@ -104,8 +99,7 @@ abstract contract IBCAppBase is IIBCModule {
      * NOTE: You should apply an `onlyIBC` modifier to the function if a derived contract overrides it.
      */
     function onChanCloseConfirm(
-        string calldata portId,
-        string calldata channelId,
+        uint32 channelId,
         address relayer
     ) external virtual override onlyIBC {}
 
@@ -115,7 +109,7 @@ abstract contract IBCAppBase is IIBCModule {
      * NOTE: You should apply an `onlyIBC` modifier to the function if a derived contract overrides it.
      */
     function onRecvPacket(
-        IbcCoreChannelV1Packet.Data calldata packet,
+        IBCPacket calldata packet,
         address relayer
     )
         external
@@ -131,7 +125,7 @@ abstract contract IBCAppBase is IIBCModule {
      * NOTE: You should apply an `onlyIBC` modifier to the function if a derived contract overrides it.
      */
     function onAcknowledgementPacket(
-        IbcCoreChannelV1Packet.Data calldata packet,
+        IBCPacket calldata packet,
         bytes calldata acknowledgement,
         address relayer
     ) external virtual override onlyIBC {}
@@ -142,7 +136,7 @@ abstract contract IBCAppBase is IIBCModule {
      * NOTE: You should apply an `onlyIBC` modifier to the function if a derived contract overrides it.
      */
     function onTimeoutPacket(
-        IbcCoreChannelV1Packet.Data calldata packet,
+        IBCPacket calldata packet,
         address relayer
     ) external virtual override onlyIBC {}
 }
diff --git a/evm/contracts/clients/CometblsClientV2.sol b/evm/contracts/clients/CometblsClientV2.sol
index 27b051f5b8..5193d0078c 100644
--- a/evm/contracts/clients/CometblsClientV2.sol
+++ b/evm/contracts/clients/CometblsClientV2.sol
@@ -20,7 +20,15 @@ import "../lib/ICS23.sol";
 import "./ICS23MembershipVerifier.sol";
 import "./Verifier.sol";
 
-struct OptimizedConsensusState {
+struct ClientState {
+    string chainId;
+    uint64 trustingPeriod;
+    uint64 maxClockDrift;
+    IBCHeight frozenHeight;
+    IBCHeight latestHeight;
+}
+
+struct ConsensusState {
     uint64 timestamp;
     bytes32 appHash;
     bytes32 nextValidatorsHash;
@@ -39,6 +47,8 @@ library CometblsClientLib {
     error ErrInvalidMisbehaviorHeadersSequence();
     error ErrInvalidMisbehavior();
     error ErrClientFrozen();
+    error ErrChainIdTooLong();
+    error ErrInvalidInitialConsensusState();
 
     function isExpired(
         uint64 headerTime,
@@ -82,32 +92,33 @@ library CometblsClientLib {
         return header;
     }
 
-    function encodeMemory(
-        UnionIbcLightclientsCometblsV1ClientState.Data memory clientState
-    ) internal pure returns (bytes memory) {
+    function encodeMemory(ClientState memory clientState)
+        internal
+        pure
+        returns (bytes memory)
+    {
         return abi.encode(
-            clientState.chain_id,
-            clientState.trusting_period,
-            clientState.unbonding_period,
-            clientState.max_clock_drift,
-            clientState.frozen_height,
-            clientState.latest_height
+            clientState.chainId,
+            clientState.trustingPeriod,
+            clientState.maxClockDrift,
+            clientState.frozenHeight,
+            clientState.latestHeight
         );
     }
 
     function decodeClientState(bytes calldata bz)
         internal
         pure
-        returns (UnionIbcLightclientsCometblsV1ClientState.Data calldata)
+        returns (ClientState calldata)
     {
-        UnionIbcLightclientsCometblsV1ClientState.Data calldata clientState;
+        ClientState calldata clientState;
         assembly {
             clientState := bz.offset
         }
         return clientState;
     }
 
-    function encodeMemory(OptimizedConsensusState memory consensusState)
+    function encodeMemory(ConsensusState memory consensusState)
         internal
         pure
         returns (bytes memory)
@@ -122,9 +133,9 @@ library CometblsClientLib {
     function decodeConsensusState(bytes calldata bz)
         internal
         pure
-        returns (OptimizedConsensusState calldata)
+        returns (ConsensusState calldata)
     {
-        OptimizedConsensusState calldata consensusState;
+        ConsensusState calldata consensusState;
         assembly {
             consensusState := bz.offset
         }
@@ -134,9 +145,9 @@ library CometblsClientLib {
     function decodeConsensusStateMemory(bytes memory bz)
         internal
         pure
-        returns (OptimizedConsensusState memory)
+        returns (ConsensusState memory)
     {
-        OptimizedConsensusState memory consensusState;
+        ConsensusState memory consensusState;
         (uint64 timestamp, bytes32 appHash, bytes32 nextValidatorsHash) =
             abi.decode(bz, (uint64, bytes32, bytes32));
         consensusState.timestamp = timestamp;
@@ -145,7 +156,7 @@ library CometblsClientLib {
         return consensusState;
     }
 
-    function commit(OptimizedConsensusState memory consensusState)
+    function commit(ConsensusState memory consensusState)
         internal
         pure
         returns (bytes32)
@@ -153,9 +164,11 @@ library CometblsClientLib {
         return keccak256(encodeMemory(consensusState));
     }
 
-    function commit(
-        UnionIbcLightclientsCometblsV1ClientState.Data memory clientState
-    ) internal pure returns (bytes32) {
+    function commit(ClientState memory clientState)
+        internal
+        pure
+        returns (bytes32)
+    {
         return keccak256(encodeMemory(clientState));
     }
 }
@@ -168,16 +181,15 @@ contract CometblsClient is
     PausableUpgradeable
 {
     using BytesLib for bytes;
-    using IBCHeight for IbcCoreClientV1Height.Data;
+    using IBCHeightLib for *;
     using CometblsClientLib for *;
 
     address private ibcHandler;
 
-    mapping(string => UnionIbcLightclientsCometblsV1ClientState.Data) private
-        clientStates;
-    mapping(string => mapping(uint128 => OptimizedConsensusState)) private
+    mapping(uint32 => ClientState) private clientStates;
+    mapping(uint32 => mapping(uint128 => ConsensusState)) private
         consensusStates;
-    mapping(string => mapping(uint128 => ProcessedMoment)) private
+    mapping(uint32 => mapping(uint128 => ProcessedMoment)) private
         processedMoments;
 
     constructor() {
@@ -193,82 +205,74 @@ contract CometblsClient is
     }
 
     function createClient(
-        string calldata clientId,
+        uint32 clientId,
         bytes calldata clientStateBytes,
         bytes calldata consensusStateBytes
-    )
-        external
-        override
-        onlyIBC
-        returns (
-            bytes32 clientStateCommitment,
-            ConsensusStateUpdate memory update,
-            bool ok
-        )
-    {
-        UnionIbcLightclientsCometblsV1ClientState.Data calldata clientState =
-            clientStateBytes.decodeClientState();
-        OptimizedConsensusState calldata consensusState =
+    ) external override onlyIBC returns (ConsensusStateUpdate memory update) {
+        ClientState calldata clientState = clientStateBytes.decodeClientState();
+        ConsensusState calldata consensusState =
             consensusStateBytes.decodeConsensusState();
         if (
-            clientState.latest_height.revision_height == 0
+            clientState.latestHeight.revisionHeight == 0
                 || consensusState.timestamp == 0
         ) {
-            return (clientStateCommitment, update, false);
+            revert CometblsClientLib.ErrInvalidInitialConsensusState();
         }
         // ChainID can't exceed 31 bytes (ensures its big-endian repr fit in F_r)
-        if (bytes(clientState.chain_id).length > 31) {
-            return (clientStateCommitment, update, false);
+        if (bytes(clientState.chainId).length > 31) {
+            revert CometblsClientLib.ErrChainIdTooLong();
         }
         clientStates[clientId] = clientState;
-        uint128 latestHeight = clientState.latest_height.toUint128();
+        uint128 latestHeight = clientState.latestHeight.toUint128();
         consensusStates[clientId][latestHeight] = consensusState;
         // Normalize to nanosecond because ibc-go recvPacket expects nanos...
         processedMoments[clientId][latestHeight] = ProcessedMoment({
             timestamp: block.timestamp * 1e9,
             height: block.number
         });
-        return (
-            clientState.commit(),
-            ConsensusStateUpdate({
-                consensusStateCommitment: consensusState.commit(),
-                height: clientState.latest_height
-            }),
-            true
-        );
+        return ConsensusStateUpdate({
+            clientStateCommitment: clientState.commit(),
+            consensusStateCommitment: consensusState.commit(),
+            height: clientState.latestHeight
+        });
     }
 
     function misbehavior(
-        string calldata clientId,
+        uint32 clientId,
         UnionIbcLightclientsCometblsV1Header.Data calldata headerA,
         UnionIbcLightclientsCometblsV1Header.Data calldata headerB
     ) public {
-        UnionIbcLightclientsCometblsV1ClientState.Data storage clientState =
-            clientStates[clientId];
+        ClientState storage clientState = clientStates[clientId];
         bool fraud = checkMisbehavior(clientId, clientState, headerA, headerB);
         if (!fraud) {
             revert CometblsClientLib.ErrInvalidMisbehavior();
         }
         // Similar to tendermint https://github.com/cosmos/ibc-go/blob/bbdcc8c6e965c8a2f607dfb2b61cd13712dd966a/modules/light-clients/07-tendermint/misbehaviour.go#L19
-        clientState.frozen_height =
-            IbcCoreClientV1Height.Data({revision_number: 0, revision_height: 1});
+        clientState.frozenHeight =
+            IBCHeight({revisionNumber: 0, revisionHeight: 1});
     }
 
     function checkMisbehavior(
-        string calldata clientId,
-        UnionIbcLightclientsCometblsV1ClientState.Data storage clientState,
+        uint32 clientId,
+        ClientState storage clientState,
         UnionIbcLightclientsCometblsV1Header.Data calldata headerA,
         UnionIbcLightclientsCometblsV1Header.Data calldata headerB
     ) internal returns (bool) {
         // Ensures that A >= B to simplify the misbehavior of time violation check
-        if (!headerA.trusted_height.gte(headerB.trusted_height)) {
+        if (
+            !headerA.trusted_height.convert().gte(
+                headerB.trusted_height.convert()
+            )
+        ) {
             revert CometblsClientLib.ErrInvalidMisbehaviorHeadersSequence();
         }
 
-        OptimizedConsensusState storage consensusStateA =
-            consensusStates[clientId][headerA.trusted_height.toUint128()];
-        OptimizedConsensusState storage consensusStateB =
-            consensusStates[clientId][headerB.trusted_height.toUint128()];
+        ConsensusState storage consensusStateA = consensusStates[clientId][headerA
+            .trusted_height
+            .convert().toUint128()];
+        ConsensusState storage consensusStateB = consensusStates[clientId][headerB
+            .trusted_height
+            .convert().toUint128()];
 
         // Check that the headers would have been accepted in an update
         (, uint64 untrustedTimestampA,) =
@@ -276,7 +280,11 @@ contract CometblsClient is
         (, uint64 untrustedTimestampB,) =
             verifyHeader(headerB, consensusStateB, clientState);
 
-        if (headerA.trusted_height.eq(headerB.trusted_height)) {
+        if (
+            headerA.trusted_height.convert().eq(
+                headerB.trusted_height.convert()
+            )
+        ) {
             bytes32 hashA = keccak256(abi.encode(headerA.signed_header));
             bytes32 hashB = keccak256(abi.encode(headerB.signed_header));
             if (hashA != hashB) {
@@ -295,8 +303,8 @@ contract CometblsClient is
 
     function verifyHeader(
         UnionIbcLightclientsCometblsV1Header.Data calldata header,
-        OptimizedConsensusState storage consensusState,
-        UnionIbcLightclientsCometblsV1ClientState.Data storage clientState
+        ConsensusState storage consensusState,
+        ClientState storage clientState
     ) internal returns (uint64, uint64, bytes32) {
         if (consensusState.timestamp == 0) {
             revert CometblsClientLib.ErrTrustedConsensusStateNotFound();
@@ -320,13 +328,13 @@ contract CometblsClient is
         uint64 currentTime = uint64(block.timestamp * 1e9);
         if (
             CometblsClientLib.isExpired(
-                untrustedTimestamp, clientState.trusting_period, currentTime
+                untrustedTimestamp, clientState.trustingPeriod, currentTime
             )
         ) {
             revert CometblsClientLib.ErrHeaderExpired();
         }
 
-        uint64 maxClockDrift = currentTime + clientState.max_clock_drift;
+        uint64 maxClockDrift = currentTime + clientState.maxClockDrift;
 
         if (untrustedTimestamp >= maxClockDrift) {
             revert CometblsClientLib.ErrMaxClockDriftExceeded();
@@ -351,7 +359,7 @@ contract CometblsClient is
 
         bool ok = internalVerifyZKP(
             header.zero_knowledge_proof,
-            clientState.chain_id,
+            clientState.chainId,
             trustedValidatorsHash,
             header.signed_header
         );
@@ -364,38 +372,32 @@ contract CometblsClient is
     }
 
     function updateClient(
-        string calldata clientId,
+        uint32 clientId,
         bytes calldata clientMessageBytes
-    )
-        external
-        override
-        onlyIBC
-        returns (bytes32, ConsensusStateUpdate[] memory)
-    {
+    ) external override onlyIBC returns (ConsensusStateUpdate memory) {
         UnionIbcLightclientsCometblsV1Header.Data calldata header =
             clientMessageBytes.decodeHeader();
-        UnionIbcLightclientsCometblsV1ClientState.Data storage clientState =
-            clientStates[clientId];
+        ClientState storage clientState = clientStates[clientId];
 
-        if (!clientState.frozen_height.isZero()) {
+        if (!clientState.frozenHeight.isZero()) {
             revert CometblsClientLib.ErrClientFrozen();
         }
 
-        OptimizedConsensusState storage consensusState =
-            consensusStates[clientId][header.trusted_height.toUint128()];
+        ConsensusState storage consensusState = consensusStates[clientId][header
+            .trusted_height
+            .convert().toUint128()];
 
         (uint64 untrustedHeightNumber, uint64 untrustedTimestamp,) =
             verifyHeader(header, consensusState, clientState);
 
         // Update states
-        if (untrustedHeightNumber > clientState.latest_height.revision_height) {
-            clientState.latest_height.revision_height = untrustedHeightNumber;
+        if (untrustedHeightNumber > clientState.latestHeight.revisionHeight) {
+            clientState.latestHeight.revisionHeight = untrustedHeightNumber;
         }
 
-        IbcCoreClientV1Height.Data memory untrustedHeight =
-        IbcCoreClientV1Height.Data({
-            revision_number: header.trusted_height.revision_number,
-            revision_height: untrustedHeightNumber
+        IBCHeight memory untrustedHeight = IBCHeight({
+            revisionNumber: header.trusted_height.revision_number,
+            revisionHeight: untrustedHeightNumber
         });
 
         uint128 untrustedHeightIndex = untrustedHeight.toUint128();
@@ -411,18 +413,16 @@ contract CometblsClient is
         processed.timestamp = block.timestamp * 1e9;
         processed.height = block.number;
 
-        ConsensusStateUpdate[] memory updates = new ConsensusStateUpdate[](1);
-        updates[0] = ConsensusStateUpdate({
+        return ConsensusStateUpdate({
+            clientStateCommitment: clientState.commit(),
             consensusStateCommitment: consensusState.commit(),
             height: untrustedHeight
         });
-
-        return (clientState.commit(), updates);
     }
 
     function verifyMembership(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height,
+        uint32 clientId,
+        IBCHeight calldata height,
         uint64 delayPeriodTime,
         uint64 delayPeriodBlocks,
         bytes calldata proof,
@@ -442,8 +442,8 @@ contract CometblsClient is
     }
 
     function verifyNonMembership(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height,
+        uint32 clientId,
+        IBCHeight calldata height,
         uint64 delayPeriodTime,
         uint64 delayPeriodBlocks,
         bytes calldata proof,
@@ -462,12 +462,12 @@ contract CometblsClient is
     }
 
     function validateDelayPeriod(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height,
+        uint32 clientId,
+        IBCHeight calldata height,
         uint64 delayPeriodTime,
         uint64 delayPeriodBlocks
     ) internal view returns (bytes32) {
-        OptimizedConsensusState storage consensusState =
+        ConsensusState storage consensusState =
             consensusStates[clientId][height.toUint128()];
         if (consensusState.timestamp == 0) {
             revert CometblsClientLib.ErrTrustedConsensusStateNotFound();
@@ -487,7 +487,7 @@ contract CometblsClient is
         return consensusState.appHash;
     }
 
-    function getClientState(string calldata clientId)
+    function getClientState(uint32 clientId)
         external
         view
         returns (bytes memory)
@@ -496,43 +496,34 @@ contract CometblsClient is
     }
 
     function getConsensusState(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height
+        uint32 clientId,
+        IBCHeight calldata height
     ) external view returns (bytes memory) {
         return consensusStates[clientId][height.toUint128()].encodeMemory();
     }
 
     function getTimestampAtHeight(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height
+        uint32 clientId,
+        IBCHeight calldata height
     ) external view override returns (uint64) {
         return consensusStates[clientId][height.toUint128()].timestamp;
     }
 
-    function getLatestHeight(string calldata clientId)
+    function getLatestHeight(uint32 clientId)
         external
         view
         override
-        returns (IbcCoreClientV1Height.Data memory)
+        returns (IBCHeight memory)
     {
-        return clientStates[clientId].latest_height;
+        return clientStates[clientId].latestHeight;
     }
 
-    function isFrozen(string calldata clientId)
-        external
-        view
-        virtual
-        returns (bool)
-    {
+    function isFrozen(uint32 clientId) external view virtual returns (bool) {
         return isFrozenImpl(clientId);
     }
 
-    function isFrozenImpl(string calldata clientId)
-        internal
-        view
-        returns (bool)
-    {
-        return !clientStates[clientId].frozen_height.isZero();
+    function isFrozenImpl(uint32 clientId) internal view returns (bool) {
+        return !clientStates[clientId].frozenHeight.isZero();
     }
 
     // ZKP VERIFICATION
@@ -629,7 +620,7 @@ contract CometblsClient is
         onlyOwner
     {}
 
-    function _onlyIBC() private view {
+    function _onlyIBC() internal view {
         if (msg.sender != ibcHandler) {
             revert CometblsClientLib.ErrNotIBC();
         }
diff --git a/evm/contracts/clients/CosmosInCosmosClient.sol b/evm/contracts/clients/CosmosInCosmosClient.sol
index 28ef2bad32..1dd25c7e28 100644
--- a/evm/contracts/clients/CosmosInCosmosClient.sol
+++ b/evm/contracts/clients/CosmosInCosmosClient.sol
@@ -16,10 +16,6 @@ import {IbcLightclientsTendermintV1ConsensusState as TendermintConsensusState}
 import "../proto/cosmos/ics23/v1/proofs.sol";
 import "../proto/tendermint/types/types.sol";
 import "../proto/tendermint/types/canonical.sol";
-import {
-    UnionIbcLightclientsCosmosincosmosV1ClientState as CosmosInCosmosClientState,
-    UnionIbcLightclientsCosmosincosmosV1Header as CosmosInCosmosHeader
-} from "../proto/union/ibc/lightclients/cosmosincosmos/v1/cosmosincosmos.sol";
 import {UnionIbcLightclientsCometblsV1ClientState as CometblsClientState} from
     "../proto/union/ibc/lightclients/cometbls/v1/cometbls.sol";
 import "../proto/ibc/lightclients/wasm/v1/wasm.sol";
@@ -27,7 +23,21 @@ import "../lib/ICS23.sol";
 import "./ICS23MembershipVerifier.sol";
 import {ProcessedMoment} from "../lib/Common.sol";
 
-struct OptimizedCosmosInCosmosConsensusState {
+struct Header {
+    IBCHeight l1Height;
+    IBCHeight l2Height;
+    bytes l2InclusionProof;
+    bytes l2ConsensusState;
+}
+
+struct ClientState {
+    string l2ChainId;
+    uint32 l1ClientId;
+    uint32 l2ClientId;
+    IBCHeight latestHeight;
+}
+
+struct ConsensusState {
     uint64 timestamp;
     bytes32 appHash;
 }
@@ -38,8 +48,9 @@ library CosmosInCosmosLib {
     error ErrDelayPeriodNotExpired();
     error ErrClientFrozen();
     error ErrInvalidL1Proof();
+    error ErrInvalidInitialConsensusState();
 
-    function encode(OptimizedCosmosInCosmosConsensusState memory consensusState)
+    function encode(ConsensusState memory consensusState)
         internal
         pure
         returns (bytes memory)
@@ -47,20 +58,20 @@ library CosmosInCosmosLib {
         return abi.encode(consensusState.timestamp, consensusState.appHash);
     }
 
-    function encode(CosmosInCosmosClientState.Data memory clientState)
+    function encode(ClientState memory clientState)
         internal
         pure
         returns (bytes memory)
     {
         return abi.encode(
-            clientState.l2_chain_id,
-            clientState.l1_client_id,
-            clientState.l2_client_id,
-            clientState.latest_height
+            clientState.l2ChainId,
+            clientState.l1ClientId,
+            clientState.l2ClientId,
+            clientState.latestHeight
         );
     }
 
-    function commit(OptimizedCosmosInCosmosConsensusState memory consensusState)
+    function commit(ConsensusState memory consensusState)
         internal
         pure
         returns (bytes32)
@@ -68,7 +79,7 @@ library CosmosInCosmosLib {
         return keccak256(encode(consensusState));
     }
 
-    function commit(CosmosInCosmosClientState.Data memory clientState)
+    function commit(ClientState memory clientState)
         internal
         pure
         returns (bytes32)
@@ -85,15 +96,15 @@ contract CosmosInCosmosClient is
     PausableUpgradeable
 {
     using BytesLib for bytes;
-    using IBCHeight for IbcCoreClientV1Height.Data;
+    using IBCHeightLib for IBCHeight;
     using CosmosInCosmosLib for *;
 
     address private ibcHandler;
 
-    mapping(string => CosmosInCosmosClientState.Data) private clientStates;
-    mapping(string => mapping(uint128 => OptimizedCosmosInCosmosConsensusState))
-        private consensusStates;
-    mapping(string => mapping(uint128 => ProcessedMoment)) private
+    mapping(uint32 => ClientState) private clientStates;
+    mapping(uint32 => mapping(uint128 => ConsensusState)) private
+        consensusStates;
+    mapping(uint32 => mapping(uint128 => ProcessedMoment)) private
         processedMoments;
 
     constructor() {
@@ -109,49 +120,37 @@ contract CosmosInCosmosClient is
     }
 
     function createClient(
-        string calldata clientId,
+        uint32 clientId,
         bytes calldata clientStateBytes,
         bytes calldata consensusStateBytes
-    )
-        external
-        override
-        onlyIBC
-        returns (
-            bytes32 clientStateCommitment,
-            ConsensusStateUpdate memory update,
-            bool ok
-        )
-    {
-        CosmosInCosmosClientState.Data calldata clientState;
+    ) external override onlyIBC returns (ConsensusStateUpdate memory update) {
+        ClientState calldata clientState;
         assembly {
             clientState := clientStateBytes.offset
         }
-        OptimizedCosmosInCosmosConsensusState calldata consensusState;
+        ConsensusState calldata consensusState;
         assembly {
             consensusState := consensusStateBytes.offset
         }
         if (
-            clientState.latest_height.revision_height == 0
+            clientState.latestHeight.revisionHeight == 0
                 || consensusState.timestamp == 0
         ) {
-            return (clientStateCommitment, update, false);
+            revert CosmosInCosmosLib.ErrInvalidInitialConsensusState();
         }
         clientStates[clientId] = clientState;
-        uint128 latestHeight = clientState.latest_height.toUint128();
+        uint128 latestHeight = clientState.latestHeight.toUint128();
         consensusStates[clientId][latestHeight] = consensusState;
         // Normalize to nanosecond because ibc-go recvPacket expects nanos...
         processedMoments[clientId][latestHeight] = ProcessedMoment({
             timestamp: block.timestamp * 1e9,
             height: block.number
         });
-        return (
-            clientState.commit(),
-            ConsensusStateUpdate({
-                consensusStateCommitment: consensusState.commit(),
-                height: clientState.latest_height
-            }),
-            true
-        );
+        return ConsensusStateUpdate({
+            clientStateCommitment: clientState.commit(),
+            consensusStateCommitment: consensusState.commit(),
+            height: clientState.latestHeight
+        });
     }
 
     /*
@@ -159,49 +158,43 @@ contract CosmosInCosmosClient is
      * Given an L₂ and L₁ heights (H₂, H₁), we prove that L₂[H₂] ∈ L₁[H₁].
      */
     function updateClient(
-        string calldata clientId,
+        uint32 clientId,
         bytes calldata clientMessageBytes
-    )
-        external
-        override
-        onlyIBC
-        returns (bytes32, ConsensusStateUpdate[] memory)
-    {
-        CosmosInCosmosHeader.Data calldata header;
+    ) external override onlyIBC returns (ConsensusStateUpdate memory) {
+        Header calldata header;
         assembly {
             header := clientMessageBytes.offset
         }
-        CosmosInCosmosClientState.Data memory clientState =
-            clientStates[clientId];
+        ClientState memory clientState = clientStates[clientId];
         ILightClient l1Client =
-            IBCStore(ibcHandler).getClient(clientState.l1_client_id);
+            IBCStore(ibcHandler).getClient(clientState.l1ClientId);
         // L₂[H₂] ∈ L₁[H₁]
         if (
             !l1Client.verifyMembership(
-                clientState.l1_client_id,
-                header.l1_height,
+                clientState.l1ClientId,
+                header.l1Height,
                 0,
                 0,
-                header.l2_inclusion_proof,
-                bytes(IBCStoreLib.COMMITMENT_PREFIX),
+                header.l2InclusionProof,
+                abi.encodePacked(IBCStoreLib.COMMITMENT_PREFIX),
                 IBCCommitment.consensusStatePath(
-                    clientState.l2_client_id,
-                    header.l2_height.revision_number,
-                    header.l2_height.revision_height
+                    clientState.l2ClientId,
+                    header.l2Height.revisionNumber,
+                    header.l2Height.revisionHeight
                 ),
-                header.l2_consensus_state
+                header.l2ConsensusState
             )
         ) {
             revert CosmosInCosmosLib.ErrInvalidL1Proof();
         }
         TendermintConsensusState.Data memory l2ConsensusState =
-            TendermintConsensusState.decode(header.l2_consensus_state);
+            TendermintConsensusState.decode(header.l2ConsensusState);
 
-        if (header.l2_height.gt(clientState.latest_height)) {
-            clientState.latest_height = header.l2_height;
+        if (header.l2Height.gt(clientState.latestHeight)) {
+            clientState.latestHeight = header.l2Height;
         }
 
-        uint128 l2HeightIndex = header.l2_height.toUint128();
+        uint128 l2HeightIndex = header.l2Height.toUint128();
 
         // Cosmos expects nanos...
         uint64 l2Timestamp = uint64(l2ConsensusState.timestamp.secs) * 1e9
@@ -210,7 +203,7 @@ contract CosmosInCosmosClient is
         // L₂[H₂] = optimize(S₂)
         // The default tendermint consensus state is stored as protobuf.
         // We use ethereum native encoding to make it more efficient.
-        OptimizedCosmosInCosmosConsensusState storage consensusState =
+        ConsensusState storage consensusState =
             consensusStates[clientId][l2HeightIndex];
         consensusState.timestamp = l2Timestamp;
         consensusState.appHash = l2ConsensusState.root.hash.toBytes32(0);
@@ -222,18 +215,16 @@ contract CosmosInCosmosClient is
         processed.height = block.number;
 
         // commit(optimize(S₂))
-        ConsensusStateUpdate[] memory updates = new ConsensusStateUpdate[](1);
-        updates[0] = ConsensusStateUpdate({
+        return ConsensusStateUpdate({
+            clientStateCommitment: clientState.commit(),
             consensusStateCommitment: consensusState.commit(),
-            height: header.l2_height
+            height: header.l2Height
         });
-
-        return (clientState.commit(), updates);
     }
 
     function verifyMembership(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height,
+        uint32 clientId,
+        IBCHeight calldata height,
         uint64 delayPeriodTime,
         uint64 delayPeriodBlocks,
         bytes calldata proof,
@@ -253,8 +244,8 @@ contract CosmosInCosmosClient is
     }
 
     function verifyNonMembership(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height,
+        uint32 clientId,
+        IBCHeight calldata height,
         uint64 delayPeriodTime,
         uint64 delayPeriodBlocks,
         bytes calldata proof,
@@ -273,12 +264,12 @@ contract CosmosInCosmosClient is
     }
 
     function validateDelayPeriod(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height,
+        uint32 clientId,
+        IBCHeight calldata height,
         uint64 delayPeriodTime,
         uint64 delayPeriodBlocks
     ) internal view returns (bytes32) {
-        OptimizedCosmosInCosmosConsensusState storage consensusState =
+        ConsensusState storage consensusState =
             consensusStates[clientId][height.toUint128()];
         if (consensusState.timestamp == 0) {
             revert CosmosInCosmosLib.ErrTrustedConsensusStateNotFound();
@@ -298,7 +289,7 @@ contract CosmosInCosmosClient is
         return consensusState.appHash;
     }
 
-    function getClientState(string calldata clientId)
+    function getClientState(uint32 clientId)
         external
         view
         returns (bytes memory)
@@ -307,43 +298,34 @@ contract CosmosInCosmosClient is
     }
 
     function getConsensusState(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height
+        uint32 clientId,
+        IBCHeight calldata height
     ) external view returns (bytes memory) {
         return consensusStates[clientId][height.toUint128()].encode();
     }
 
     function getTimestampAtHeight(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height
+        uint32 clientId,
+        IBCHeight calldata height
     ) external view override returns (uint64) {
         return consensusStates[clientId][height.toUint128()].timestamp;
     }
 
-    function getLatestHeight(string calldata clientId)
+    function getLatestHeight(uint32 clientId)
         external
         view
         override
-        returns (IbcCoreClientV1Height.Data memory)
+        returns (IBCHeight memory)
     {
-        return clientStates[clientId].latest_height;
+        return clientStates[clientId].latestHeight;
     }
 
-    function isFrozen(string calldata clientId)
-        external
-        view
-        virtual
-        returns (bool)
-    {
+    function isFrozen(uint32 clientId) external view virtual returns (bool) {
         return isFrozenImpl(clientId);
     }
 
-    function isFrozenImpl(string calldata clientId)
-        internal
-        view
-        returns (bool)
-    {
-        string memory l1ClientId = clientStates[clientId].l1_client_id;
+    function isFrozenImpl(uint32 clientId) internal view returns (bool) {
+        uint32 l1ClientId = clientStates[clientId].l1ClientId;
         return IBCStore(ibcHandler).getClient(l1ClientId).isFrozen(l1ClientId);
     }
 
@@ -353,7 +335,7 @@ contract CosmosInCosmosClient is
         onlyOwner
     {}
 
-    function _onlyIBC() private view {
+    function _onlyIBC() internal view {
         if (msg.sender != ibcHandler) {
             revert CosmosInCosmosLib.ErrNotIBC();
         }
diff --git a/evm/contracts/core/02-client/IBCClient.sol b/evm/contracts/core/02-client/IBCClient.sol
index b883e2896d..1dcfca501e 100644
--- a/evm/contracts/core/02-client/IBCClient.sol
+++ b/evm/contracts/core/02-client/IBCClient.sol
@@ -1,34 +1,30 @@
 pragma solidity ^0.8.23;
 
-import "@openzeppelin/utils/Strings.sol";
 import "./ILightClient.sol";
 import "../25-handler/IBCMsgs.sol";
 import "../24-host/IBCStore.sol";
 import "../24-host/IBCCommitment.sol";
 import "../02-client/IIBCClient.sol";
-import "../../proto/ibc/core/client/v1/client.sol";
 
 library IBCClientLib {
-    event ClientRegistered(string clientType, address clientAddress);
-    event ClientCreated(string clientId);
-    event ClientUpdated(string clientId, IbcCoreClientV1Height.Data height);
+    event ClientRegistered(bytes32 clientType, address clientAddress);
+    event ClientCreated(uint32 clientId);
+    event ClientUpdated(uint32 clientId, IBCHeight height);
 
     error ErrClientTypeAlreadyExists();
     error ErrClientMustNotBeSelf();
     error ErrClientTypeNotFound();
-    error ErrFailedToCreateClient();
-    error ErrFailedToUpdateClient();
 }
 
 /**
  * @dev IBCClient is a contract that implements [ICS-2](https://github.com/cosmos/ibc/tree/main/spec/core/ics-002-client-semantics).
  */
-contract IBCClient is IBCStore, IIBCClient {
+abstract contract IBCClient is IBCStore, IIBCClient {
     /**
      * @dev registerClient registers a new client type into the client registry
      */
     function registerClient(
-        string calldata clientType,
+        bytes32 clientType,
         ILightClient client
     ) external override {
         if (address(clientRegistry[clientType]) != address(0)) {
@@ -38,7 +34,6 @@ contract IBCClient is IBCStore, IIBCClient {
             revert IBCClientLib.ErrClientMustNotBeSelf();
         }
         clientRegistry[clientType] = address(client);
-
         emit IBCClientLib.ClientRegistered(clientType, address(client));
     }
 
@@ -48,37 +43,23 @@ contract IBCClient is IBCStore, IIBCClient {
     function createClient(IBCMsgs.MsgCreateClient calldata msg_)
         external
         override
-        returns (string memory clientId)
+        returns (uint32)
     {
         address clientImpl = clientRegistry[msg_.clientType];
         if (clientImpl == address(0)) {
             revert IBCClientLib.ErrClientTypeNotFound();
         }
-        clientId = generateClientIdentifier(msg_.clientType);
+        uint32 clientId = generateClientIdentifier();
         clientTypes[clientId] = msg_.clientType;
         clientImpls[clientId] = clientImpl;
-        (
-            bytes32 clientStateCommitment,
-            ConsensusStateUpdate memory update,
-            bool ok
-        ) = ILightClient(clientImpl).createClient(
-            clientId, msg_.clientStateBytes, msg_.consensusStateBytes
-        );
-        if (!ok) {
-            revert IBCClientLib.ErrFailedToCreateClient();
-        }
-
-        // update commitments
+        ConsensusStateUpdate memory update = ILightClient(clientImpl)
+            .createClient(clientId, msg_.clientStateBytes, msg_.consensusStateBytes);
         commitments[keccak256(IBCCommitment.clientStatePath(clientId))] =
-            clientStateCommitment;
+            update.clientStateCommitment;
         commitments[IBCCommitment.consensusStateCommitmentKey(
-            clientId,
-            update.height.revision_number,
-            update.height.revision_height
+            clientId, update.height.revisionNumber, update.height.revisionHeight
         )] = update.consensusStateCommitment;
-
         emit IBCClientLib.ClientCreated(clientId);
-
         return clientId;
     }
 
@@ -89,47 +70,23 @@ contract IBCClient is IBCStore, IIBCClient {
         external
         override
     {
-        if (
-            commitments[IBCCommitment.clientStateCommitmentKey(msg_.clientId)]
-                == bytes32(0)
-        ) {
-            revert IBCStoreLib.ErrClientNotFound();
-        }
-        (bytes32 clientStateCommitment, ConsensusStateUpdate[] memory updates) =
-        getClient(msg_.clientId).updateClient(msg_.clientId, msg_.clientMessage);
-        uint256 updatesLength = updates.length;
-        if (updatesLength == 0) {
-            revert IBCClientLib.ErrFailedToUpdateClient();
-        }
-
-        // update commitments
+        ConsensusStateUpdate memory update = getClientInternal(msg_.clientId)
+            .updateClient(msg_.clientId, msg_.clientMessage);
         commitments[keccak256(IBCCommitment.clientStatePath(msg_.clientId))] =
-            clientStateCommitment;
-        for (uint256 i; i < updatesLength; i++) {
-            commitments[IBCCommitment.consensusStateCommitmentKey(
-                msg_.clientId,
-                updates[i].height.revision_number,
-                updates[i].height.revision_height
-            )] = updates[i].consensusStateCommitment;
-            emit IBCClientLib.ClientUpdated(msg_.clientId, updates[i].height);
-        }
+            update.clientStateCommitment;
+        commitments[IBCCommitment.consensusStateCommitmentKey(
+            msg_.clientId,
+            update.height.revisionNumber,
+            update.height.revisionHeight
+        )] = update.consensusStateCommitment;
+        emit IBCClientLib.ClientUpdated(msg_.clientId, update.height);
     }
 
-    function generateClientIdentifier(string calldata clientType)
-        private
-        returns (string memory)
-    {
-        uint256 nextClientSequence =
-            uint256(commitments[nextClientSequencePath]);
-
-        string memory identifier = string(
-            abi.encodePacked(
-                clientType, "-", Strings.toString(nextClientSequence)
-            )
-        );
-
-        commitments[nextClientSequencePath] = bytes32(nextClientSequence + 1);
-
-        return identifier;
+    function generateClientIdentifier() internal returns (uint32) {
+        uint32 nextClientSequence =
+            uint32(uint256(commitments[nextClientSequencePath]));
+        commitments[nextClientSequencePath] =
+            bytes32(uint256(nextClientSequence + 1));
+        return nextClientSequence;
     }
 }
diff --git a/evm/contracts/core/02-client/IBCHeight.sol b/evm/contracts/core/02-client/IBCHeight.sol
index f6d7cb8d31..7885afbe61 100644
--- a/evm/contracts/core/02-client/IBCHeight.sol
+++ b/evm/contracts/core/02-client/IBCHeight.sol
@@ -1,89 +1,93 @@
 pragma solidity ^0.8.23;
 
 import "../../proto/ibc/core/client/v1/client.sol";
+import "../Types.sol";
 
-library IBCHeight {
-    function toUint128(IbcCoreClientV1Height.Data memory self)
+library IBCHeightLib {
+    function convert(IbcCoreClientV1Height.Data memory self)
         internal
         pure
-        returns (uint128)
+        returns (IBCHeight memory)
     {
-        return (uint128(self.revision_number) << 64)
-            | uint128(self.revision_height);
+        return IBCHeight({
+            revisionNumber: self.revision_number,
+            revisionHeight: self.revision_height
+        });
+    }
+
+    function toUint128(IBCHeight memory self) internal pure returns (uint128) {
+        return
+            (uint128(self.revisionNumber) << 64) | uint128(self.revisionHeight);
     }
 
     function fromUint128(uint128 composite)
         internal
         pure
-        returns (IbcCoreClientV1Height.Data memory)
+        returns (IBCHeight memory)
     {
-        return IbcCoreClientV1Height.Data({
-            revision_number: uint64(composite >> 64),
-            revision_height: uint64(composite)
+        return IBCHeight({
+            revisionNumber: uint64(composite >> 64),
+            revisionHeight: uint64(composite)
         });
     }
 
-    function isZero(IbcCoreClientV1Height.Data memory self)
-        internal
-        pure
-        returns (bool)
-    {
-        return self.revision_number == 0 && self.revision_height == 0;
+    function isZero(IBCHeight memory self) internal pure returns (bool) {
+        return self.revisionNumber == 0 && self.revisionHeight == 0;
     }
 
     function lt(
-        IbcCoreClientV1Height.Data memory self,
-        IbcCoreClientV1Height.Data memory other
+        IBCHeight memory self,
+        IBCHeight memory other
     ) internal pure returns (bool) {
-        return self.revision_number < other.revision_number
+        return self.revisionNumber < other.revisionNumber
             || (
-                self.revision_number == other.revision_number
-                    && self.revision_height < other.revision_height
+                self.revisionNumber == other.revisionNumber
+                    && self.revisionHeight < other.revisionHeight
             );
     }
 
     function lte(
-        IbcCoreClientV1Height.Data memory self,
-        IbcCoreClientV1Height.Data memory other
+        IBCHeight memory self,
+        IBCHeight memory other
     ) internal pure returns (bool) {
-        return self.revision_number < other.revision_number
+        return self.revisionNumber < other.revisionNumber
             || (
-                self.revision_number == other.revision_number
-                    && self.revision_height <= other.revision_height
+                self.revisionNumber == other.revisionNumber
+                    && self.revisionHeight <= other.revisionHeight
             );
     }
 
     function eq(
-        IbcCoreClientV1Height.Data memory self,
-        IbcCoreClientV1Height.Data memory other
+        IBCHeight memory self,
+        IBCHeight memory other
     ) internal pure returns (bool) {
-        return self.revision_number == other.revision_number
-            && self.revision_height == other.revision_height;
+        return self.revisionNumber == other.revisionNumber
+            && self.revisionHeight == other.revisionHeight;
     }
 
     function gt(
-        IbcCoreClientV1Height.Data memory self,
-        IbcCoreClientV1Height.Data memory other
+        IBCHeight memory self,
+        IBCHeight memory other
     ) internal pure returns (bool) {
-        return self.revision_number > other.revision_number
+        return self.revisionNumber > other.revisionNumber
             || (
-                self.revision_number == other.revision_number
-                    && self.revision_height > other.revision_height
+                self.revisionNumber == other.revisionNumber
+                    && self.revisionHeight > other.revisionHeight
             );
     }
 
     function gte(
-        IbcCoreClientV1Height.Data memory self,
-        IbcCoreClientV1Height.Data memory other
+        IBCHeight memory self,
+        IBCHeight memory other
     ) internal pure returns (bool) {
-        return self.revision_number > other.revision_number
+        return self.revisionNumber > other.revisionNumber
             || (
-                self.revision_number == other.revision_number
-                    && self.revision_height >= other.revision_height
+                self.revisionNumber == other.revisionNumber
+                    && self.revisionHeight >= other.revisionHeight
             );
     }
 
-    function zero() internal pure returns (IbcCoreClientV1Height.Data memory) {
+    function zero() internal pure returns (IBCHeight memory) {
         return fromUint128(0);
     }
 }
diff --git a/evm/contracts/core/02-client/IIBCClient.sol b/evm/contracts/core/02-client/IIBCClient.sol
index ac0fc74494..ca355f7356 100644
--- a/evm/contracts/core/02-client/IIBCClient.sol
+++ b/evm/contracts/core/02-client/IIBCClient.sol
@@ -7,17 +7,14 @@ interface IIBCClient {
     /**
      * @dev registerClient registers a new client type into the client registry
      */
-    function registerClient(
-        string calldata clientType,
-        ILightClient client
-    ) external;
+    function registerClient(bytes32 clientType, ILightClient client) external;
 
     /**
      * @dev createClient creates a new client state and populates it with a given consensus state
      */
     function createClient(IBCMsgs.MsgCreateClient calldata msg_)
         external
-        returns (string memory clientId);
+        returns (uint32 clientId);
 
     /**
      * @dev updateClient updates the consensus state and the state root from a provided header
diff --git a/evm/contracts/core/02-client/ILightClient.sol b/evm/contracts/core/02-client/ILightClient.sol
index 4e38c762cd..8e07da3cae 100644
--- a/evm/contracts/core/02-client/ILightClient.sol
+++ b/evm/contracts/core/02-client/ILightClient.sol
@@ -1,12 +1,11 @@
 pragma solidity ^0.8.23;
 
-import "../../proto/ibc/core/client/v1/client.sol";
+import "../Types.sol";
 
 struct ConsensusStateUpdate {
-    // commitment for updated consensusState
+    bytes32 clientStateCommitment;
     bytes32 consensusStateCommitment;
-    // updated height
-    IbcCoreClientV1Height.Data height;
+    IBCHeight height;
 }
 
 /**
@@ -19,32 +18,26 @@ interface ILightClient {
      * If succeeded, it returns a commitment for the initial state.
      */
     function createClient(
-        string calldata clientId,
+        uint32 clientId,
         bytes calldata clientStateBytes,
         bytes calldata consensusStateBytes
-    )
-        external
-        returns (
-            bytes32 clientStateCommitment,
-            ConsensusStateUpdate memory update,
-            bool ok
-        );
+    ) external returns (ConsensusStateUpdate memory update);
 
     /**
      * @dev getTimestampAtHeight returns the timestamp of the consensus state at the given height.
      */
     function getTimestampAtHeight(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height
+        uint32 clientId,
+        IBCHeight calldata height
     ) external view returns (uint64);
 
     /**
      * @dev getLatestHeight returns the latest height of the client state corresponding to `clientId`.
      */
-    function getLatestHeight(string calldata clientId)
+    function getLatestHeight(uint32 clientId)
         external
         view
-        returns (IbcCoreClientV1Height.Data memory);
+        returns (IBCHeight memory);
 
     /**
      * @dev updateClient updates the client corresponding to `clientId`.
@@ -59,22 +52,17 @@ interface ILightClient {
      * 5. persist the state(s) on the host
      */
     function updateClient(
-        string calldata clientId,
+        uint32 clientId,
         bytes calldata clientMessageBytes
-    )
-        external
-        returns (
-            bytes32 clientStateCommitment,
-            ConsensusStateUpdate[] memory updates
-        );
+    ) external returns (ConsensusStateUpdate memory update);
 
     /**
      * @dev verifyMembership is a generic proof verification method which verifies a proof of the existence of a value at a given CommitmentPath at the specified height.
      * The caller is expected to construct the full CommitmentPath from a CommitmentPrefix and a standardized path (as defined in ICS 24).
      */
     function verifyMembership(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height,
+        uint32 clientId,
+        IBCHeight calldata height,
         uint64 delayTimePeriod,
         uint64 delayBlockPeriod,
         bytes calldata proof,
@@ -88,8 +76,8 @@ interface ILightClient {
      * The caller is expected to construct the full CommitmentPath from a CommitmentPrefix and a standardized path (as defined in ICS 24).
      */
     function verifyNonMembership(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height,
+        uint32 clientId,
+        IBCHeight calldata height,
         uint64 delayTimePeriod,
         uint64 delayBlockPeriod,
         bytes calldata proof,
@@ -100,7 +88,7 @@ interface ILightClient {
     /**
      * @dev getClientState returns the clientState corresponding to `clientId`.
      */
-    function getClientState(string calldata clientId)
+    function getClientState(uint32 clientId)
         external
         view
         returns (bytes memory);
@@ -109,12 +97,12 @@ interface ILightClient {
      * @dev getConsensusState returns the consensusState corresponding to `clientId` and `height`.
      */
     function getConsensusState(
-        string calldata clientId,
-        IbcCoreClientV1Height.Data calldata height
+        uint32 clientId,
+        IBCHeight calldata height
     ) external view returns (bytes memory);
 
     /**
      * @dev isFrozen returns whether the `clientId` is frozen or not.
      */
-    function isFrozen(string calldata clientId) external view returns (bool);
+    function isFrozen(uint32 clientId) external view returns (bool);
 }
diff --git a/evm/contracts/core/03-connection/IBCConnection.sol b/evm/contracts/core/03-connection/IBCConnection.sol
index 4d0c9a7e8d..d4d96c6abb 100644
--- a/evm/contracts/core/03-connection/IBCConnection.sol
+++ b/evm/contracts/core/03-connection/IBCConnection.sol
@@ -1,335 +1,41 @@
 pragma solidity ^0.8.23;
 
-import "solady/utils/LibString.sol";
-import "@openzeppelin/utils/Strings.sol";
-import "../../proto/ibc/core/client/v1/client.sol";
-import "../../proto/ibc/core/connection/v1/connection.sol";
-import "../25-handler/IBCMsgs.sol";
 import "../24-host/IBCStore.sol";
+import "../25-handler/IBCMsgs.sol";
 import "../24-host/IBCCommitment.sol";
 import "../03-connection/IIBCConnection.sol";
 
 library IBCConnectionLib {
     event ConnectionOpenInit(
-        string connectionId, string clientId, string counterpartyClientId
+        uint32 connectionId, uint32 clientId, uint32 counterpartyClientId
     );
     event ConnectionOpenTry(
-        string connectionId,
-        string clientId,
-        string counterpartyClientId,
-        string counterpartyConnectionId
+        uint32 connectionId,
+        uint32 clientId,
+        uint32 counterpartyClientId,
+        uint32 counterpartyConnectionId
     );
     event ConnectionOpenAck(
-        string connectionId,
-        string clientId,
-        string counterpartyClientId,
-        string counterpartyConnectionId
+        uint32 connectionId,
+        uint32 clientId,
+        uint32 counterpartyClientId,
+        uint32 counterpartyConnectionId
     );
     event ConnectionOpenConfirm(
-        string connectionId,
-        string clientId,
-        string counterpartyClientId,
-        string counterpartyConnectionId
+        uint32 connectionId,
+        uint32 clientId,
+        uint32 counterpartyClientId,
+        uint32 counterpartyConnectionId
     );
 
-    error ErrConnectionAlreadyExists();
-    error ErrValidateSelfClient();
-    error ErrNoCounterpartyVersion();
-    error ErrUnsupportedVersion();
-    error ErrVersionMustBeUnset();
     error ErrInvalidProof();
     error ErrInvalidConnectionState();
-
-    // yes, these are all defined as strings in the ibc spec
-    string internal constant IBC_VERSION_IDENTIFIER = "1";
-    string internal constant ORDER_ORDERED = "ORDER_ORDERED";
-    string internal constant ORDER_UNORDERED = "ORDER_UNORDERED";
-
-    /**
-     * @dev defaultIBCVersion returns the latest supported version of IBC used in connection version negotiation
-     */
-    function defaultIBCVersion()
-        internal
-        pure
-        returns (IbcCoreConnectionV1Version.Data memory)
-    {
-        IbcCoreConnectionV1Version.Data memory version =
-        IbcCoreConnectionV1Version.Data({
-            identifier: IBC_VERSION_IDENTIFIER,
-            features: new string[](2)
-        });
-        version.features[0] = ORDER_ORDERED;
-        version.features[1] = ORDER_UNORDERED;
-        return version;
-    }
-
-    /**
-     * @dev setSupportedVersions sets the supported versions to a given array.
-     *
-     * NOTE: `dst` must be an empty array
-     */
-    function setSupportedVersions(
-        IbcCoreConnectionV1Version.Data[] memory supportedVersions,
-        IbcCoreConnectionV1Version.Data[] storage dst
-    ) internal {
-        if (dst.length != 0) {
-            revert ErrVersionMustBeUnset();
-        }
-        uint256 supportedVersionsLength = supportedVersions.length;
-        for (uint256 i; i < supportedVersionsLength; i++) {
-            dst.push(supportedVersions[i]);
-        }
-    }
-
-    /**
-     * @dev isSupportedVersion returns true if the proposed version has a matching version
-     * identifier and its entire feature set is supported or the version identifier
-     * supports an empty feature set.
-     */
-    function isSupportedVersion(
-        IbcCoreConnectionV1Version.Data[] memory supportedVersions,
-        IbcCoreConnectionV1Version.Data memory version
-    ) internal pure returns (bool) {
-        (IbcCoreConnectionV1Version.Data memory supportedVersion, bool found) =
-            findSupportedVersion(version, supportedVersions);
-        if (!found) {
-            return false;
-        }
-        return verifyProposedVersion(supportedVersion, version);
-    }
-
-    function isSupported(
-        IbcCoreConnectionV1Version.Data[] storage supportedVersions,
-        string memory feature
-    ) internal view returns (bool) {
-        uint256 supportedVersionsLength = supportedVersions.length;
-        for (uint256 i; i < supportedVersionsLength; i++) {
-            if (verifySupportedFeature(supportedVersions[i], feature)) {
-                return true;
-            }
-        }
-        return false;
-    }
-
-    /**
-     * @dev verifyProposedVersion verifies that the entire feature set in the
-     * proposed version is supported by this chain. If the feature set is
-     * empty it verifies that this is allowed for the specified version
-     * identifier.
-     */
-    function verifyProposedVersion(
-        IbcCoreConnectionV1Version.Data memory supportedVersion,
-        IbcCoreConnectionV1Version.Data memory proposedVersion
-    ) internal pure returns (bool) {
-        if (
-            keccak256(abi.encodePacked(proposedVersion.identifier))
-                != keccak256(abi.encodePacked(supportedVersion.identifier))
-        ) {
-            return false;
-        }
-        uint256 proposedVersionFeaturesLength = proposedVersion.features.length;
-        if (proposedVersionFeaturesLength == 0) {
-            return false;
-        }
-        for (uint256 i; i < proposedVersionFeaturesLength; i++) {
-            if (
-                !contains(proposedVersion.features[i], supportedVersion.features)
-            ) {
-                return false;
-            }
-        }
-        return true;
-    }
-
-    /**
-     * @dev findSupportedVersion returns the version with a matching version identifier
-     * if it exists. The returned boolean is true if the version is found and
-     * false otherwise.
-     */
-    function findSupportedVersion(
-        IbcCoreConnectionV1Version.Data memory version,
-        IbcCoreConnectionV1Version.Data[] memory supportedVersions
-    )
-        internal
-        pure
-        returns (
-            IbcCoreConnectionV1Version.Data memory supportedVersion,
-            bool found
-        )
-    {
-        uint256 supportedVersionsLength = supportedVersions.length;
-        for (uint256 i; i < supportedVersionsLength; i++) {
-            supportedVersion = supportedVersions[i];
-            if (
-                keccak256(abi.encodePacked(supportedVersion.identifier))
-                    == keccak256(abi.encodePacked(version.identifier))
-            ) {
-                return (supportedVersion, true);
-            }
-        }
-        return (supportedVersion, false);
-    }
-
-    function pickVersion(
-        IbcCoreConnectionV1Version.Data[] memory supportedVersions,
-        IbcCoreConnectionV1Version.Data[] memory counterpartyVersions
-    ) internal pure returns (IbcCoreConnectionV1Version.Data memory) {
-        uint256 supportedVersionsLength = supportedVersions.length;
-        for (uint256 i; i < supportedVersionsLength; i++) {
-            IbcCoreConnectionV1Version.Data memory supportedVersion =
-                supportedVersions[i];
-            (
-                IbcCoreConnectionV1Version.Data memory counterpartyVersion,
-                bool found
-            ) = findSupportedVersion(supportedVersion, counterpartyVersions);
-            if (!found) {
-                continue;
-            }
-            string[] memory featureSet = getFeatureSetIntersection(
-                supportedVersion.features, counterpartyVersion.features
-            );
-            if (featureSet.length > 0) {
-                return IbcCoreConnectionV1Version.Data({
-                    identifier: supportedVersion.identifier,
-                    features: featureSet
-                });
-            }
-        }
-        revert ErrUnsupportedVersion();
-    }
-
-    /**
-     * @dev copyVersions copies `src` to `dst`
-     */
-    function copyVersions(
-        IbcCoreConnectionV1Version.Data[] memory src,
-        IbcCoreConnectionV1Version.Data[] storage dst
-    ) internal {
-        uint256 srcLength = src.length;
-        uint256 dstLength = dst.length;
-        if (srcLength == dstLength) {
-            for (uint256 i; i < srcLength; i++) {
-                copyVersion(src[i], dst[i]);
-            }
-        } else if (srcLength > dstLength) {
-            for (uint256 i; i < dstLength; i++) {
-                copyVersion(src[i], dst[i]);
-            }
-            for (uint256 i = dstLength; i < srcLength; i++) {
-                dst.push(src[i]);
-            }
-        } else {
-            for (uint256 i; i < srcLength; i++) {
-                copyVersion(src[i], dst[i]);
-            }
-            for (uint256 i = srcLength; i < dstLength; i++) {
-                dst.pop();
-            }
-        }
-    }
-
-    /**
-     * @dev newVersions returns a new array with a given version
-     */
-    function newVersions(IbcCoreConnectionV1Version.Data memory version)
-        internal
-        pure
-        returns (IbcCoreConnectionV1Version.Data[] memory ret)
-    {
-        ret = new IbcCoreConnectionV1Version.Data[](1);
-        ret[0] = version;
-    }
-
-    /**
-     * @dev verifySupportedFeature takes in a version and feature string and returns
-     * true if the feature is supported by the version and false otherwise.
-     */
-    function verifySupportedFeature(
-        IbcCoreConnectionV1Version.Data memory version,
-        string memory feature
-    ) internal pure returns (bool) {
-        bytes32 hashedFeature = keccak256(bytes(feature));
-        uint256 versionFeaturesLength = version.features.length;
-        for (uint256 i; i < versionFeaturesLength; i++) {
-            if (keccak256(bytes(version.features[i])) == hashedFeature) {
-                return true;
-            }
-        }
-        return false;
-    }
-
-    function getFeatureSetIntersection(
-        string[] memory sourceFeatureSet,
-        string[] memory counterpartyFeatureSet
-    ) private pure returns (string[] memory) {
-        uint256 sourceFeatureSetLength = sourceFeatureSet.length;
-        string[] memory featureSet = new string[](sourceFeatureSetLength);
-        uint256 featureSetLength;
-        for (uint256 i; i < sourceFeatureSetLength; i++) {
-            if (contains(sourceFeatureSet[i], counterpartyFeatureSet)) {
-                featureSet[featureSetLength] = sourceFeatureSet[i];
-                featureSetLength++;
-            }
-        }
-        string[] memory ret = new string[](featureSetLength);
-        for (uint256 i; i < featureSetLength; i++) {
-            ret[i] = featureSet[i];
-        }
-        return ret;
-    }
-
-    function copyVersion(
-        IbcCoreConnectionV1Version.Data memory src,
-        IbcCoreConnectionV1Version.Data storage dst
-    ) private {
-        dst.identifier = src.identifier;
-        uint256 srcLength = src.features.length;
-        uint256 dstLength = dst.features.length;
-
-        if (srcLength == dstLength) {
-            for (uint256 i; i < srcLength; i++) {
-                dst.features[i] = src.features[i];
-            }
-        } else if (srcLength > dstLength) {
-            for (uint256 i; i < dstLength; i++) {
-                dst.features[i] = src.features[i];
-            }
-            for (uint256 i = dstLength; i < srcLength; i++) {
-                dst.features.push(src.features[i]);
-            }
-        } else {
-            for (uint256 i; i < srcLength; i++) {
-                dst.features[i] = src.features[i];
-            }
-            for (uint256 i = srcLength; i < dstLength; i++) {
-                dst.features.pop();
-            }
-        }
-    }
-
-    function contains(
-        string memory elem,
-        string[] memory set
-    ) private pure returns (bool) {
-        bytes32 hashedElem = keccak256(bytes(elem));
-        uint256 setLength = set.length;
-        for (uint256 i; i < setLength; i++) {
-            if (keccak256(bytes(set[i])) == hashedElem) {
-                return true;
-            }
-        }
-        return false;
-    }
 }
 
 /**
  * @dev IBCConnection is a contract that implements [ICS-3](https://github.com/cosmos/ibc/tree/main/spec/core/ics-003-connection-semantics).
  */
-contract IBCConnection is IBCStore, IIBCConnectionHandshake {
-    using LibString for *;
-
-    /* Handshake functions */
-
+abstract contract IBCConnectionImpl is IBCStore, IIBCConnection {
     /**
      * @dev connectionOpenInit initialises a connection attempt on chain A. The generated connection identifier
      * is returned.
@@ -337,46 +43,18 @@ contract IBCConnection is IBCStore, IIBCConnectionHandshake {
     function connectionOpenInit(IBCMsgs.MsgConnectionOpenInit calldata msg_)
         external
         override
-        returns (string memory)
+        returns (uint32)
     {
-        string memory connectionId = generateConnectionIdentifier();
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection =
-            connections[connectionId];
-        if (
-            connection.state
-                != IbcCoreConnectionV1GlobalEnums
-                    .State
-                    .STATE_UNINITIALIZED_UNSPECIFIED
-        ) {
-            revert IBCConnectionLib.ErrConnectionAlreadyExists();
-        }
-
-        connection.client_id = msg_.clientId;
-
-        if (msg_.version.features.length > 0) {
-            if (
-                !IBCConnectionLib.isSupportedVersion(
-                    getCompatibleVersions(), msg_.version
-                )
-            ) {
-                revert IBCConnectionLib.ErrUnsupportedVersion();
-            }
-            connection.versions.push(msg_.version);
-        } else {
-            IBCConnectionLib.setSupportedVersions(
-                getCompatibleVersions(), connection.versions
-            );
-        }
-
-        connection.state = IbcCoreConnectionV1GlobalEnums.State.STATE_INIT;
-        connection.delay_period = msg_.delayPeriod;
+        uint32 connectionId = generateConnectionIdentifier();
+        IBCConnection storage connection = connections[connectionId];
+        connection.clientId = msg_.clientId;
+        connection.state = IBCConnectionState.Init;
+        connection.delayPeriod = msg_.delayPeriod;
         connection.counterparty = msg_.counterparty;
-        updateConnectionCommitment(connectionId);
-
+        commitConnection(connectionId, connection);
         emit IBCConnectionLib.ConnectionOpenInit(
-            connectionId, msg_.clientId, msg_.counterparty.client_id
+            connectionId, msg_.clientId, msg_.counterparty.clientId
         );
-
         return connectionId;
     }
 
@@ -387,85 +65,42 @@ contract IBCConnection is IBCStore, IIBCConnectionHandshake {
     function connectionOpenTry(IBCMsgs.MsgConnectionOpenTry calldata msg_)
         external
         override
-        returns (string memory)
+        returns (uint32)
     {
-        if (!validateSelfClient(msg_.clientStateBytes)) {
-            revert IBCConnectionLib.ErrValidateSelfClient();
-        }
-        if (msg_.counterpartyVersions.length == 0) {
-            revert IBCConnectionLib.ErrNoCounterpartyVersion();
-        }
-
-        string memory connectionId = generateConnectionIdentifier();
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection =
-            connections[connectionId];
-
-        if (
-            connection.state
-                != IbcCoreConnectionV1GlobalEnums
-                    .State
-                    .STATE_UNINITIALIZED_UNSPECIFIED
-        ) {
-            revert IBCConnectionLib.ErrConnectionAlreadyExists();
-        }
-
-        connection.client_id = msg_.clientId;
-        connection.versions.push(
-            IBCConnectionLib.pickVersion(
-                getCompatibleVersions(), msg_.counterpartyVersions
-            )
-        );
-        connection.state = IbcCoreConnectionV1GlobalEnums.State.STATE_TRYOPEN;
-        connection.delay_period = msg_.delayPeriod;
+        uint32 connectionId = generateConnectionIdentifier();
+        IBCConnection storage connection = connections[connectionId];
+        connection.clientId = msg_.clientId;
+        connection.state = IBCConnectionState.TryOpen;
+        connection.delayPeriod = msg_.delayPeriod;
         connection.counterparty = msg_.counterparty;
-
-        IbcCoreConnectionV1ConnectionEnd.Data memory expectedConnection =
-        IbcCoreConnectionV1ConnectionEnd.Data({
-            client_id: msg_.counterparty.client_id,
-            versions: msg_.counterpartyVersions,
-            state: IbcCoreConnectionV1GlobalEnums.State.STATE_INIT,
-            delay_period: msg_.delayPeriod,
-            counterparty: IbcCoreConnectionV1Counterparty.Data({
-                client_id: msg_.clientId,
-                connection_id: "",
-                prefix: IbcCoreCommitmentV1MerklePrefix.Data({
-                    key_prefix: bytes(COMMITMENT_PREFIX)
-                })
+        IBCConnection memory expectedConnection = IBCConnection({
+            clientId: msg_.counterparty.clientId,
+            state: IBCConnectionState.Init,
+            delayPeriod: msg_.delayPeriod,
+            counterparty: IBCConnectionCounterparty({
+                clientId: msg_.clientId,
+                connectionId: 0,
+                merklePrefix: COMMITMENT_PREFIX
             })
         });
-
         if (
             !verifyConnectionState(
                 connection,
                 msg_.proofHeight,
                 msg_.proofInit,
-                msg_.counterparty.connection_id,
+                msg_.counterparty.connectionId,
                 expectedConnection
             )
         ) {
             revert IBCConnectionLib.ErrInvalidProof();
         }
-        if (
-            !verifyClientState(
-                connection,
-                msg_.proofHeight,
-                IBCCommitment.clientStatePath(connection.counterparty.client_id),
-                msg_.proofClient,
-                msg_.clientStateBytes
-            )
-        ) {
-            revert IBCConnectionLib.ErrInvalidProof();
-        }
-
-        updateConnectionCommitment(connectionId);
-
+        commitConnection(connectionId, connection);
         emit IBCConnectionLib.ConnectionOpenTry(
             connectionId,
             msg_.clientId,
-            msg_.counterparty.client_id,
-            msg_.counterparty.connection_id
+            msg_.counterparty.clientId,
+            msg_.counterparty.connectionId
         );
-
         return connectionId;
     }
 
@@ -477,76 +112,41 @@ contract IBCConnection is IBCStore, IIBCConnectionHandshake {
         external
         override
     {
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection =
-            connections[msg_.connectionId];
-        if (connection.state != IbcCoreConnectionV1GlobalEnums.State.STATE_INIT)
-        {
+        IBCConnection storage connection = connections[msg_.connectionId];
+        if (connection.state != IBCConnectionState.Init) {
             revert IBCConnectionLib.ErrInvalidConnectionState();
         }
-        if (
-            !IBCConnectionLib.isSupportedVersion(
-                connection.versions, msg_.version
-            )
-        ) {
-            revert IBCConnectionLib.ErrUnsupportedVersion();
-        }
-        if (!validateSelfClient(msg_.clientStateBytes)) {
-            revert IBCConnectionLib.ErrValidateSelfClient();
-        }
-
-        IbcCoreConnectionV1Counterparty.Data memory expectedCounterparty =
-        IbcCoreConnectionV1Counterparty.Data({
-            client_id: connection.client_id,
-            connection_id: msg_.connectionId,
-            prefix: IbcCoreCommitmentV1MerklePrefix.Data({
-                key_prefix: bytes(COMMITMENT_PREFIX)
-            })
+        IBCConnectionCounterparty memory expectedCounterparty =
+        IBCConnectionCounterparty({
+            clientId: connection.clientId,
+            connectionId: msg_.connectionId,
+            merklePrefix: COMMITMENT_PREFIX
         });
-
-        IbcCoreConnectionV1ConnectionEnd.Data memory expectedConnection =
-        IbcCoreConnectionV1ConnectionEnd.Data({
-            client_id: connection.counterparty.client_id,
-            versions: IBCConnectionLib.newVersions(msg_.version),
-            state: IbcCoreConnectionV1GlobalEnums.State.STATE_TRYOPEN,
-            delay_period: connection.delay_period,
+        IBCConnection memory expectedConnection = IBCConnection({
+            clientId: connection.counterparty.clientId,
+            state: IBCConnectionState.TryOpen,
+            delayPeriod: connection.delayPeriod,
             counterparty: expectedCounterparty
         });
-
         if (
             !verifyConnectionState(
                 connection,
                 msg_.proofHeight,
                 msg_.proofTry,
-                msg_.counterpartyConnectionID,
+                msg_.counterpartyConnectionId,
                 expectedConnection
             )
         ) {
             revert IBCConnectionLib.ErrInvalidProof();
         }
-        if (
-            !verifyClientState(
-                connection,
-                msg_.proofHeight,
-                IBCCommitment.clientStatePath(connection.counterparty.client_id),
-                msg_.proofClient,
-                msg_.clientStateBytes
-            )
-        ) {
-            revert IBCConnectionLib.ErrInvalidProof();
-        }
-
-        connection.state = IbcCoreConnectionV1GlobalEnums.State.STATE_OPEN;
-        IBCConnectionLib.copyVersions(
-            expectedConnection.versions, connection.versions
-        );
-        connection.counterparty.connection_id = msg_.counterpartyConnectionID;
-        updateConnectionCommitment(msg_.connectionId);
-
+        connection.state = IBCConnectionState.Open;
+        connection.counterparty.connectionId = msg_.counterpartyConnectionId;
+        commitConnection(msg_.connectionId, connection);
         emit IBCConnectionLib.ConnectionOpenAck(
             msg_.connectionId,
-            connection.client_id,
-            connection.counterparty.client_id,
-            connection.counterparty.connection_id
+            connection.clientId,
+            connection.counterparty.clientId,
+            connection.counterparty.connectionId
         );
     }
 
@@ -557,145 +157,91 @@ contract IBCConnection is IBCStore, IIBCConnectionHandshake {
     function connectionOpenConfirm(
         IBCMsgs.MsgConnectionOpenConfirm calldata msg_
     ) external override {
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection =
-            connections[msg_.connectionId];
-        if (
-            connection.state
-                != IbcCoreConnectionV1GlobalEnums.State.STATE_TRYOPEN
-        ) {
+        IBCConnection storage connection = connections[msg_.connectionId];
+        if (connection.state != IBCConnectionState.TryOpen) {
             revert IBCConnectionLib.ErrInvalidConnectionState();
         }
-
-        IbcCoreConnectionV1Counterparty.Data memory expectedCounterparty =
-        IbcCoreConnectionV1Counterparty.Data({
-            client_id: connection.client_id,
-            connection_id: msg_.connectionId,
-            prefix: IbcCoreCommitmentV1MerklePrefix.Data({
-                key_prefix: bytes(COMMITMENT_PREFIX)
-            })
+        IBCConnectionCounterparty memory expectedCounterparty =
+        IBCConnectionCounterparty({
+            clientId: connection.clientId,
+            connectionId: msg_.connectionId,
+            merklePrefix: COMMITMENT_PREFIX
         });
-
-        IbcCoreConnectionV1ConnectionEnd.Data memory expectedConnection =
-        IbcCoreConnectionV1ConnectionEnd.Data({
-            client_id: connection.counterparty.client_id,
-            versions: connection.versions,
-            state: IbcCoreConnectionV1GlobalEnums.State.STATE_OPEN,
-            delay_period: connection.delay_period,
+        IBCConnection memory expectedConnection = IBCConnection({
+            clientId: connection.counterparty.clientId,
+            state: IBCConnectionState.Open,
+            delayPeriod: connection.delayPeriod,
             counterparty: expectedCounterparty
         });
-
         if (
             !verifyConnectionState(
                 connection,
                 msg_.proofHeight,
                 msg_.proofAck,
-                connection.counterparty.connection_id,
+                connection.counterparty.connectionId,
                 expectedConnection
             )
         ) {
             revert IBCConnectionLib.ErrInvalidProof();
         }
-
-        connection.state = IbcCoreConnectionV1GlobalEnums.State.STATE_OPEN;
-        updateConnectionCommitment(msg_.connectionId);
-
+        connection.state = IBCConnectionState.Open;
+        commitConnection(msg_.connectionId, connection);
         emit IBCConnectionLib.ConnectionOpenConfirm(
             msg_.connectionId,
-            connection.client_id,
-            connection.counterparty.client_id,
-            connection.counterparty.connection_id
+            connection.clientId,
+            connection.counterparty.clientId,
+            connection.counterparty.connectionId
         );
     }
 
-    function updateConnectionCommitment(string memory connectionId) private {
-        commitments[IBCCommitment.connectionCommitmentKey(connectionId)] =
-        keccak256(
-            IbcCoreConnectionV1ConnectionEnd.encode(connections[connectionId])
-        );
+    function encodeConnection(IBCConnection memory connection)
+        internal
+        pure
+        returns (bytes32)
+    {
+        return keccak256(abi.encode(connection));
     }
 
-    /* Verification functions */
+    function encodeConnectionStorage(IBCConnection storage connection)
+        internal
+        pure
+        returns (bytes32)
+    {
+        return keccak256(abi.encode(connection));
+    }
 
-    function verifyClientState(
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection,
-        IbcCoreClientV1Height.Data memory height,
-        bytes memory path,
-        bytes memory proof,
-        bytes memory clientStateBytes
-    ) private returns (bool) {
-        return getClient(connection.client_id).verifyMembership(
-            connection.client_id,
-            height,
-            0,
-            0,
-            proof,
-            connection.counterparty.prefix.key_prefix,
-            path,
-            clientStateBytes
-        );
+    function commitConnection(
+        uint32 connectionId,
+        IBCConnection storage connection
+    ) internal {
+        commitments[IBCCommitment.connectionCommitmentKey(connectionId)] =
+            encodeConnectionStorage(connection);
     }
 
     function verifyConnectionState(
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection,
-        IbcCoreClientV1Height.Data memory height,
-        bytes memory proof,
-        string memory connectionId,
-        IbcCoreConnectionV1ConnectionEnd.Data memory counterpartyConnection
-    ) private returns (bool) {
-        return getClient(connection.client_id).verifyMembership(
-            connection.client_id,
+        IBCConnection storage connection,
+        IBCHeight calldata height,
+        bytes calldata proof,
+        uint32 connectionId,
+        IBCConnection memory counterpartyConnection
+    ) internal returns (bool) {
+        return getClientInternal(connection.clientId).verifyMembership(
+            connection.clientId,
             height,
             0,
             0,
             proof,
-            connection.counterparty.prefix.key_prefix,
+            abi.encodePacked(connection.counterparty.merklePrefix),
             IBCCommitment.connectionPath(connectionId),
-            IbcCoreConnectionV1ConnectionEnd.encode(counterpartyConnection)
+            abi.encodePacked(encodeConnection(counterpartyConnection))
         );
     }
 
-    /* Internal functions */
-
-    function generateConnectionIdentifier() private returns (string memory) {
-        uint256 nextConnectionSequence =
-            uint256(commitments[nextConnectionSequencePath]);
-
-        string memory identifier = string(
-            abi.encodePacked(
-                "connection-", Strings.toString(nextConnectionSequence)
-            )
-        );
+    function generateConnectionIdentifier() internal returns (uint32) {
+        uint32 nextConnectionSequence =
+            uint32(uint256(commitments[nextConnectionSequencePath]));
         commitments[nextConnectionSequencePath] =
-            bytes32(nextConnectionSequence + 1);
-        return identifier;
-    }
-
-    /**
-     * @dev validateSelfClient validates the client parameters for a client of the host chain.
-     *
-     * NOTE: Developers can override this function to support an arbitrary EVM chain.
-     */
-    function validateSelfClient(bytes memory)
-        internal
-        view
-        virtual
-        returns (bool)
-    {
-        return true;
-    }
-
-    /**
-     * @dev getCompatibleVersions returns the supported versions of the host chain.
-     */
-    function getCompatibleVersions()
-        public
-        pure
-        virtual
-        returns (IbcCoreConnectionV1Version.Data[] memory)
-    {
-        IbcCoreConnectionV1Version.Data[] memory versions =
-            new IbcCoreConnectionV1Version.Data[](1);
-        versions[0] = IBCConnectionLib.defaultIBCVersion();
-        return versions;
+            bytes32(uint256(nextConnectionSequence + 1));
+        return nextConnectionSequence;
     }
 }
diff --git a/evm/contracts/core/03-connection/IIBCConnection.sol b/evm/contracts/core/03-connection/IIBCConnection.sol
index ab8094ecdc..5614cc352c 100644
--- a/evm/contracts/core/03-connection/IIBCConnection.sol
+++ b/evm/contracts/core/03-connection/IIBCConnection.sol
@@ -2,7 +2,7 @@ pragma solidity ^0.8.23;
 
 import "../25-handler/IBCMsgs.sol";
 
-interface IIBCConnectionHandshake {
+interface IIBCConnection {
     /* Handshake functions */
 
     /**
@@ -11,7 +11,7 @@ interface IIBCConnectionHandshake {
      */
     function connectionOpenInit(IBCMsgs.MsgConnectionOpenInit calldata msg_)
         external
-        returns (string memory);
+        returns (uint32);
 
     /**
      * @dev connectionOpenTry relays notice of a connection attempt on chain A to chain B (this
@@ -19,7 +19,7 @@ interface IIBCConnectionHandshake {
      */
     function connectionOpenTry(IBCMsgs.MsgConnectionOpenTry calldata msg_)
         external
-        returns (string memory);
+        returns (uint32);
 
     /**
      * @dev connectionOpenAck relays acceptance of a connection open attempt from chain B back
diff --git a/evm/contracts/core/04-channel/IBCChannel.sol b/evm/contracts/core/04-channel/IBCChannel.sol
new file mode 100644
index 0000000000..fc57c47686
--- /dev/null
+++ b/evm/contracts/core/04-channel/IBCChannel.sol
@@ -0,0 +1,422 @@
+pragma solidity ^0.8.23;
+
+import "../24-host/IBCStore.sol";
+import "../25-handler/IBCMsgs.sol";
+import "../02-client/IBCHeight.sol";
+import "../24-host/IBCCommitment.sol";
+import "../04-channel/IIBCChannel.sol";
+import "../05-port/IIBCModule.sol";
+
+library IBCChannelLib {
+    event ChannelOpenInit(
+        address portId,
+        uint32 channelId,
+        bytes32 counterpartyPortId,
+        uint32 connectionId,
+        bytes32 version
+    );
+    event ChannelOpenTry(
+        address portId,
+        uint32 channelId,
+        bytes32 counterpartyPortId,
+        uint32 counterpartyChannelId,
+        uint32 connectionId,
+        bytes32 version
+    );
+    event ChannelOpenAck(
+        address portId,
+        uint32 channelId,
+        bytes32 counterpartyPortId,
+        uint32 counterpartyChannelId,
+        uint32 connectionId
+    );
+    event ChannelOpenConfirm(
+        address portId,
+        uint32 channelId,
+        bytes32 counterpartyPortId,
+        uint32 counterpartyChannelId,
+        uint32 connectionId
+    );
+    event ChannelCloseInit(address portId, uint32 channelId);
+    event ChannelCloseConfirm(address portId, uint32 channelId);
+
+    error ErrPortIdMustBeLowercase();
+    error ErrConnNotSingleHop();
+    error ErrConnNotSingleVersion();
+    error ErrInvalidConnectionState();
+    error ErrUnsupportedFeature();
+    error ErrInvalidChannelState();
+    error ErrCounterpartyChannelNotEmpty();
+    error ErrInvalidProof();
+    error ErrInvalidChannelOrdering();
+}
+
+/**
+ * @dev IBCChannelHandshake is a contract that implements [ICS-4](https://github.com/cosmos/ibc/tree/main/spec/core/ics-004-channel-and-packet-semantics).
+ */
+abstract contract IBCChannelImpl is IBCStore, IIBCChannel {
+    using IBCHeightLib for IBCHeight;
+
+    /**
+     * @dev channelOpenInit is called by a module to initiate a channel opening handshake with a module on another chain.
+     */
+    function channelOpenInit(IBCMsgs.MsgChannelOpenInit calldata msg_)
+        external
+        override
+        returns (uint32)
+    {
+        if (msg_.channel.state != IBCChannelState.Init) {
+            revert IBCChannelLib.ErrInvalidChannelState();
+        }
+        if (
+            msg_.channel.ordering != IBCChannelOrder.Unordered
+                && msg_.channel.ordering != IBCChannelOrder.Ordered
+        ) {
+            revert IBCChannelLib.ErrInvalidChannelOrdering();
+        }
+        bytes32 normalizedPortId = keccak256(abi.encodePacked(msg_.portId));
+        uint32 channelId = generateChannelIdentifier();
+        channels[channelId] = msg_.channel;
+        initializeChannelSequences(normalizedPortId, channelId);
+        commitChannelCalldata(normalizedPortId, channelId, msg_.channel);
+        claimChannel(msg_.portId, channelId);
+        IIBCModule(msg_.portId).onChanOpenInit(
+            msg_.channel.ordering,
+            msg_.channel.connectionId,
+            channelId,
+            msg_.channel.counterparty,
+            msg_.channel.version,
+            msg_.relayer
+        );
+        emit IBCChannelLib.ChannelOpenInit(
+            msg_.portId,
+            channelId,
+            msg_.channel.counterparty.portId,
+            msg_.channel.connectionId,
+            msg_.channel.version
+        );
+        return channelId;
+    }
+
+    /**
+     * @dev channelOpenTry is called by a module to accept the first step of a channel opening handshake initiated by a module on another chain.
+     */
+    function channelOpenTry(IBCMsgs.MsgChannelOpenTry calldata msg_)
+        external
+        override
+        returns (uint32)
+    {
+        if (
+            msg_.channel.ordering != IBCChannelOrder.Unordered
+                && msg_.channel.ordering != IBCChannelOrder.Ordered
+        ) {
+            revert IBCChannelLib.ErrInvalidChannelOrdering();
+        }
+        if (msg_.channel.state != IBCChannelState.TryOpen) {
+            revert IBCChannelLib.ErrInvalidChannelState();
+        }
+        IBCConnection storage connection =
+            ensureConnectionState(msg_.channel.connectionId);
+        bytes32 normalizedPortId = keccak256(abi.encodePacked(msg_.portId));
+        IBCChannelCounterparty memory expectedCounterparty =
+            IBCChannelCounterparty({portId: normalizedPortId, channelId: 0});
+        IBCChannel memory expectedChannel = IBCChannel({
+            state: IBCChannelState.Init,
+            ordering: msg_.channel.ordering,
+            counterparty: expectedCounterparty,
+            connectionId: getCounterpartyConnection(msg_.channel.connectionId),
+            version: msg_.counterpartyVersion
+        });
+        if (
+            !verifyChannelState(
+                connection,
+                msg_.proofHeight,
+                msg_.proofInit,
+                msg_.channel.counterparty.portId,
+                msg_.channel.counterparty.channelId,
+                expectedChannel
+            )
+        ) {
+            revert IBCChannelLib.ErrInvalidProof();
+        }
+        uint32 channelId = generateChannelIdentifier();
+        channels[channelId] = msg_.channel;
+        initializeChannelSequences(normalizedPortId, channelId);
+        commitChannelCalldata(normalizedPortId, channelId, msg_.channel);
+        claimChannel(msg_.portId, channelId);
+        IIBCModule(msg_.portId).onChanOpenTry(
+            msg_.channel.ordering,
+            msg_.channel.connectionId,
+            channelId,
+            msg_.channel.counterparty,
+            msg_.channel.version,
+            msg_.counterpartyVersion,
+            msg_.relayer
+        );
+        emit IBCChannelLib.ChannelOpenTry(
+            msg_.portId,
+            channelId,
+            msg_.channel.counterparty.portId,
+            msg_.channel.counterparty.channelId,
+            msg_.channel.connectionId,
+            msg_.counterpartyVersion
+        );
+        return channelId;
+    }
+
+    /**
+     * @dev channelOpenAck is called by the handshake-originating module to acknowledge the acceptance of the initial request by the counterparty module on the other chain.
+     */
+    function channelOpenAck(IBCMsgs.MsgChannelOpenAck calldata msg_)
+        external
+        override
+    {
+        IBCChannel storage channel = channels[msg_.channelId];
+        if (channel.state != IBCChannelState.Init) {
+            revert IBCChannelLib.ErrInvalidChannelState();
+        }
+        IBCConnection storage connection =
+            ensureConnectionState(channel.connectionId);
+        bytes32 normalizedPortId = keccak256(abi.encodePacked(msg_.portId));
+        IBCChannelCounterparty memory expectedCounterparty =
+        IBCChannelCounterparty({
+            portId: normalizedPortId,
+            channelId: msg_.channelId
+        });
+        IBCChannel memory expectedChannel = IBCChannel({
+            state: IBCChannelState.TryOpen,
+            ordering: channel.ordering,
+            counterparty: expectedCounterparty,
+            connectionId: getCounterpartyConnection(channel.connectionId),
+            version: msg_.counterpartyVersion
+        });
+        if (
+            !verifyChannelState(
+                connection,
+                msg_.proofHeight,
+                msg_.proofTry,
+                channel.counterparty.portId,
+                msg_.counterpartyChannelId,
+                expectedChannel
+            )
+        ) {
+            revert IBCChannelLib.ErrInvalidProof();
+        }
+        channel.state = IBCChannelState.Open;
+        channel.version = msg_.counterpartyVersion;
+        channel.counterparty.channelId = msg_.counterpartyChannelId;
+        commitChannel(normalizedPortId, msg_.channelId, channel);
+        IIBCModule(msg_.portId).onChanOpenAck(
+            msg_.channelId,
+            msg_.counterpartyChannelId,
+            msg_.counterpartyVersion,
+            msg_.relayer
+        );
+        emit IBCChannelLib.ChannelOpenAck(
+            msg_.portId,
+            msg_.channelId,
+            channel.counterparty.portId,
+            msg_.counterpartyChannelId,
+            channel.connectionId
+        );
+    }
+
+    /**
+     * @dev channelOpenConfirm is called by the counterparty module to close their end of the channel, since the other end has been closed.
+     */
+    function channelOpenConfirm(IBCMsgs.MsgChannelOpenConfirm calldata msg_)
+        external
+        override
+    {
+        IBCChannel storage channel = channels[msg_.channelId];
+        if (channel.state != IBCChannelState.TryOpen) {
+            revert IBCChannelLib.ErrInvalidChannelState();
+        }
+        IBCConnection storage connection =
+            ensureConnectionState(channel.connectionId);
+        bytes32 normalizedPortId = keccak256(abi.encodePacked(msg_.portId));
+        IBCChannelCounterparty memory expectedCounterparty =
+        IBCChannelCounterparty({
+            portId: normalizedPortId,
+            channelId: msg_.channelId
+        });
+        IBCChannel memory expectedChannel = IBCChannel({
+            state: IBCChannelState.Open,
+            ordering: channel.ordering,
+            counterparty: expectedCounterparty,
+            connectionId: getCounterpartyConnection(channel.connectionId),
+            version: channel.version
+        });
+        if (
+            !verifyChannelState(
+                connection,
+                msg_.proofHeight,
+                msg_.proofAck,
+                channel.counterparty.portId,
+                channel.counterparty.channelId,
+                expectedChannel
+            )
+        ) {
+            revert IBCChannelLib.ErrInvalidProof();
+        }
+        channel.state = IBCChannelState.Open;
+        commitChannel(normalizedPortId, msg_.channelId, channel);
+        IIBCModule(msg_.portId).onChanOpenConfirm(msg_.channelId, msg_.relayer);
+        emit IBCChannelLib.ChannelOpenConfirm(
+            msg_.portId,
+            msg_.channelId,
+            channel.counterparty.portId,
+            channel.counterparty.channelId,
+            channel.connectionId
+        );
+    }
+
+    /**
+     * @dev channelCloseInit is called by either module to close their end of the channel. Once closed, channels cannot be reopened.
+     */
+    function channelCloseInit(IBCMsgs.MsgChannelCloseInit calldata msg_)
+        external
+        override
+    {
+        IBCChannel storage channel = channels[msg_.channelId];
+        if (channel.state != IBCChannelState.Open) {
+            revert IBCChannelLib.ErrInvalidChannelState();
+        }
+        ensureConnectionState(channel.connectionId);
+        channel.state = IBCChannelState.Closed;
+        bytes32 normalizedPortId = keccak256(abi.encodePacked(msg_.portId));
+        commitChannel(normalizedPortId, msg_.channelId, channel);
+        IIBCModule(msg_.portId).onChanCloseInit(msg_.channelId, msg_.relayer);
+        emit IBCChannelLib.ChannelCloseInit(msg_.portId, msg_.channelId);
+    }
+
+    /**
+     * @dev channelCloseConfirm is called by the counterparty module to close their end of the
+     * channel, since the other end has been closed.
+     */
+    function channelCloseConfirm(IBCMsgs.MsgChannelCloseConfirm calldata msg_)
+        external
+        override
+    {
+        IBCChannel storage channel = channels[msg_.channelId];
+        if (channel.state != IBCChannelState.Open) {
+            revert IBCChannelLib.ErrInvalidChannelState();
+        }
+        IBCConnection storage connection =
+            ensureConnectionState(channel.connectionId);
+        bytes32 normalizedPortId = keccak256(abi.encodePacked(msg_.portId));
+        IBCChannelCounterparty memory expectedCounterparty =
+        IBCChannelCounterparty({
+            portId: normalizedPortId,
+            channelId: msg_.channelId
+        });
+        IBCChannel memory expectedChannel = IBCChannel({
+            state: IBCChannelState.Closed,
+            ordering: channel.ordering,
+            counterparty: expectedCounterparty,
+            connectionId: getCounterpartyConnection(channel.connectionId),
+            version: channel.version
+        });
+        if (
+            !verifyChannelState(
+                connection,
+                msg_.proofHeight,
+                msg_.proofInit,
+                channel.counterparty.portId,
+                channel.counterparty.channelId,
+                expectedChannel
+            )
+        ) {
+            revert IBCChannelLib.ErrInvalidProof();
+        }
+        channel.state = IBCChannelState.Closed;
+        commitChannel(normalizedPortId, msg_.channelId, channel);
+        IIBCModule(msg_.portId).onChanCloseConfirm(msg_.channelId, msg_.relayer);
+        emit IBCChannelLib.ChannelCloseConfirm(msg_.portId, msg_.channelId);
+    }
+
+    function encodeChannel(IBCChannel memory channel)
+        internal
+        pure
+        returns (bytes32)
+    {
+        return keccak256(abi.encode(channel));
+    }
+
+    function commitChannel(
+        bytes32 portId,
+        uint32 channelId,
+        IBCChannel storage channel
+    ) internal {
+        commitments[IBCCommitment.channelCommitmentKey(portId, channelId)] =
+            encodeChannel(channel);
+    }
+
+    function encodeChannelCalldata(IBCChannel calldata channel)
+        internal
+        pure
+        returns (bytes32)
+    {
+        return keccak256(abi.encode(channel));
+    }
+
+    function commitChannelCalldata(
+        bytes32 portId,
+        uint32 channelId,
+        IBCChannel calldata channel
+    ) internal {
+        commitments[IBCCommitment.channelCommitmentKey(portId, channelId)] =
+            encodeChannelCalldata(channel);
+    }
+
+    function verifyChannelState(
+        IBCConnection storage connection,
+        IBCHeight calldata height,
+        bytes calldata proof,
+        bytes32 portId,
+        uint32 channelId,
+        IBCChannel memory channel
+    ) internal returns (bool) {
+        return getClientInternal(connection.clientId).verifyMembership(
+            connection.clientId,
+            height,
+            0,
+            0,
+            proof,
+            abi.encodePacked(connection.counterparty.merklePrefix),
+            IBCCommitment.channelPath(portId, channelId),
+            abi.encodePacked(encodeChannel(channel))
+        );
+    }
+
+    function getCounterpartyConnection(uint32 connectionId)
+        internal
+        view
+        returns (uint32)
+    {
+        return connections[connectionId].counterparty.connectionId;
+    }
+
+    function generateChannelIdentifier() internal returns (uint32) {
+        uint32 nextChannelSequence =
+            uint32(uint256(commitments[nextChannelSequencePath]));
+        commitments[nextChannelSequencePath] =
+            bytes32(uint256(nextChannelSequence + 1));
+        return nextChannelSequence;
+    }
+
+    function initializeChannelSequences(
+        bytes32 portId,
+        uint32 channelId
+    ) internal {
+        commitments[IBCCommitment.nextSequenceSendCommitmentKey(
+            portId, channelId
+        )] = bytes32(uint256(1));
+        commitments[IBCCommitment.nextSequenceRecvCommitmentKey(
+            portId, channelId
+        )] = bytes32(uint256(1));
+        commitments[IBCCommitment.nextSequenceAckCommitmentKey(
+            portId, channelId
+        )] = bytes32(uint256(1));
+    }
+}
diff --git a/evm/contracts/core/04-channel/IBCChannelHandshake.sol b/evm/contracts/core/04-channel/IBCChannelHandshake.sol
deleted file mode 100644
index 6c29e2ed0e..0000000000
--- a/evm/contracts/core/04-channel/IBCChannelHandshake.sol
+++ /dev/null
@@ -1,551 +0,0 @@
-pragma solidity ^0.8.23;
-
-import "@openzeppelin/utils/Strings.sol";
-import "solady/utils/LibString.sol";
-
-import "../../proto/ibc/core/channel/v1/channel.sol";
-import "../25-handler/IBCMsgs.sol";
-import "../02-client/IBCHeight.sol";
-import "../24-host/IBCCommitment.sol";
-import "../04-channel/IIBCChannel.sol";
-import "../05-port/ModuleManager.sol";
-import "../05-port/IIBCModule.sol";
-
-library IBCChannelLib {
-    event ChannelOpenInit(
-        string portId,
-        string channelId,
-        string counterpartyPortId,
-        string connectionId,
-        string version
-    );
-    event ChannelOpenTry(
-        string portId,
-        string channelId,
-        string counterpartyPortId,
-        string counterpartyChannelId,
-        string connectionId,
-        string version
-    );
-    event ChannelOpenAck(
-        string portId,
-        string channelId,
-        string counterpartyPortId,
-        string counterpartyChannelId,
-        string connectionId
-    );
-    event ChannelOpenConfirm(
-        string portId,
-        string channelId,
-        string counterpartyPortId,
-        string counterpartyChannelId,
-        string connectionId
-    );
-    event ChannelCloseInit(string channelId, string portId);
-    event ChannelCloseConfirm(string channelId, string portId);
-
-    error ErrPortIdMustBeLowercase();
-    error ErrConnNotSingleHop();
-    error ErrConnNotSingleVersion();
-    error ErrInvalidConnectionState();
-    error ErrUnsupportedFeature();
-    error ErrInvalidChannelState();
-    error ErrCounterpartyChannelNotEmpty();
-    error ErrInvalidProof();
-
-    string public constant ORDER_ORDERED = "ORDER_ORDERED";
-    string public constant ORDER_UNORDERED = "ORDER_UNORDERED";
-    string public constant ORDER_INVALID = "_ORDER_INVALID_";
-
-    function verifySupportedFeature(
-        IbcCoreConnectionV1Version.Data memory version,
-        string memory feature
-    ) internal pure returns (bool) {
-        bytes32 h = keccak256(bytes(feature));
-        for (uint256 i; i < version.features.length; i++) {
-            if (keccak256(bytes(version.features[i])) == h) {
-                return true;
-            }
-        }
-        return false;
-    }
-
-    function toString(IbcCoreChannelV1GlobalEnums.Order ordering)
-        internal
-        pure
-        returns (string memory)
-    {
-        if (ordering == IbcCoreChannelV1GlobalEnums.Order.ORDER_UNORDERED) {
-            return ORDER_UNORDERED;
-        } else if (ordering == IbcCoreChannelV1GlobalEnums.Order.ORDER_ORDERED)
-        {
-            return ORDER_ORDERED;
-        } else {
-            return ORDER_INVALID;
-        }
-    }
-}
-
-/**
- * @dev IBCChannelHandshake is a contract that implements [ICS-4](https://github.com/cosmos/ibc/tree/main/spec/core/ics-004-channel-and-packet-semantics).
- */
-contract IBCChannelHandshake is ModuleManager, IIBCChannelHandshake {
-    using IBCHeight for IbcCoreClientV1Height.Data;
-    using LibString for *;
-
-    /* Handshake functions */
-
-    /**
-     * @dev channelOpenInit is called by a module to initiate a channel opening handshake with a module on another chain.
-     */
-    function channelOpenInit(IBCMsgs.MsgChannelOpenInit calldata msg_)
-        external
-        override
-        returns (string memory)
-    {
-        if (!msg_.portId.lower().eq(msg_.portId)) {
-            revert IBCChannelLib.ErrPortIdMustBeLowercase();
-        }
-        (string memory connectionId,) = ensureConnectionFeature(
-            msg_.channel.connection_hops, msg_.channel.ordering
-        );
-        if (msg_.channel.state != IbcCoreChannelV1GlobalEnums.State.STATE_INIT)
-        {
-            revert IBCChannelLib.ErrInvalidChannelState();
-        }
-        if (bytes(msg_.channel.counterparty.channel_id).length != 0) {
-            revert IBCChannelLib.ErrCounterpartyChannelNotEmpty();
-        }
-
-        string memory channelId = generateChannelIdentifier();
-        channels[msg_.portId][channelId] = msg_.channel;
-
-        commitments[IBCCommitment.nextSequenceSendCommitmentKey(
-            msg_.portId, channelId
-        )] = bytes32(uint256(1));
-        commitments[IBCCommitment.nextSequenceRecvCommitmentKey(
-            msg_.portId, channelId
-        )] = bytes32(uint256(1));
-
-        commitments[IBCCommitment.nextSequenceAckCommitmentKey(
-            msg_.portId, channelId
-        )] = bytes32(uint256(1));
-
-        updateChannelCommitment(msg_.portId, channelId);
-
-        IIBCModule module = lookupModuleByPort(msg_.portId);
-
-        claimCapability(
-            channelCapabilityPath(msg_.portId, channelId), address(module)
-        );
-
-        module.onChanOpenInit(
-            msg_.channel.ordering,
-            msg_.channel.connection_hops,
-            msg_.portId,
-            channelId,
-            msg_.channel.counterparty,
-            msg_.channel.version,
-            msg_.relayer
-        );
-
-        emit IBCChannelLib.ChannelOpenInit(
-            msg_.portId,
-            channelId,
-            msg_.channel.counterparty.port_id,
-            connectionId,
-            msg_.channel.version
-        );
-
-        return channelId;
-    }
-
-    /**
-     * @dev channelOpenTry is called by a module to accept the first step of a channel opening handshake initiated by a module on another chain.
-     */
-    function channelOpenTry(IBCMsgs.MsgChannelOpenTry calldata msg_)
-        external
-        override
-        returns (string memory)
-    {
-        if (!msg_.portId.lower().eq(msg_.portId)) {
-            revert IBCChannelLib.ErrPortIdMustBeLowercase();
-        }
-        (
-            string memory connectionId,
-            IbcCoreConnectionV1ConnectionEnd.Data memory connection
-        ) = ensureConnectionFeature(
-            msg_.channel.connection_hops, msg_.channel.ordering
-        );
-        if (
-            msg_.channel.state
-                != IbcCoreChannelV1GlobalEnums.State.STATE_TRYOPEN
-        ) {
-            revert IBCChannelLib.ErrInvalidChannelState();
-        }
-
-        IbcCoreChannelV1Counterparty.Data memory expectedCounterparty =
-        IbcCoreChannelV1Counterparty.Data({port_id: msg_.portId, channel_id: ""});
-        IbcCoreChannelV1Channel.Data memory expectedChannel =
-        IbcCoreChannelV1Channel.Data({
-            state: IbcCoreChannelV1GlobalEnums.State.STATE_INIT,
-            ordering: msg_.channel.ordering,
-            counterparty: expectedCounterparty,
-            connection_hops: getCounterpartyHops(msg_.channel.connection_hops[0]),
-            version: msg_.counterpartyVersion
-        });
-
-        if (
-            !verifyChannelState(
-                connection,
-                msg_.proofHeight,
-                msg_.proofInit,
-                msg_.channel.counterparty.port_id,
-                msg_.channel.counterparty.channel_id,
-                IbcCoreChannelV1Channel.encode(expectedChannel)
-            )
-        ) {
-            revert IBCChannelLib.ErrInvalidProof();
-        }
-
-        string memory channelId = generateChannelIdentifier();
-
-        emit IBCChannelLib.ChannelOpenTry(
-            msg_.portId,
-            channelId,
-            msg_.channel.counterparty.port_id,
-            msg_.channel.counterparty.channel_id,
-            connectionId,
-            msg_.counterpartyVersion
-        );
-
-        channels[msg_.portId][channelId] = msg_.channel;
-        commitments[IBCCommitment.nextSequenceSendCommitmentKey(
-            msg_.portId, channelId
-        )] = bytes32(uint256(1));
-        commitments[IBCCommitment.nextSequenceRecvCommitmentKey(
-            msg_.portId, channelId
-        )] = bytes32(uint256(1));
-        commitments[IBCCommitment.nextSequenceAckCommitmentKey(
-            msg_.portId, channelId
-        )] = bytes32(uint256(1));
-        updateChannelCommitment(msg_.portId, channelId);
-
-        IIBCModule module = lookupModuleByPort(msg_.portId);
-
-        claimCapability(
-            channelCapabilityPath(msg_.portId, channelId), address(module)
-        );
-
-        module.onChanOpenTry(
-            msg_.channel.ordering,
-            msg_.channel.connection_hops,
-            msg_.portId,
-            channelId,
-            msg_.channel.counterparty,
-            msg_.channel.version,
-            msg_.counterpartyVersion,
-            msg_.relayer
-        );
-
-        return channelId;
-    }
-
-    /**
-     * @dev channelOpenAck is called by the handshake-originating module to acknowledge the acceptance of the initial request by the counterparty module on the other chain.
-     */
-    function channelOpenAck(IBCMsgs.MsgChannelOpenAck calldata msg_)
-        external
-        override
-    {
-        IbcCoreChannelV1Channel.Data storage channel =
-            channels[msg_.portId][msg_.channelId];
-        if (channel.state != IbcCoreChannelV1GlobalEnums.State.STATE_INIT) {
-            revert IBCChannelLib.ErrInvalidChannelState();
-        }
-
-        emit IBCChannelLib.ChannelOpenAck(
-            msg_.portId,
-            msg_.channelId,
-            channel.counterparty.port_id,
-            // haven't been saved yet, but we have to yield the even early to avoid overflowing the stack
-            msg_.counterpartyChannelId,
-            channel.connection_hops[0]
-        );
-
-        IbcCoreConnectionV1ConnectionEnd.Data memory connection =
-            ensureConnectionState(channel.connection_hops[0]);
-
-        IbcCoreChannelV1Counterparty.Data memory expectedCounterparty =
-        IbcCoreChannelV1Counterparty.Data({
-            port_id: msg_.portId,
-            channel_id: msg_.channelId
-        });
-        IbcCoreChannelV1Channel.Data memory expectedChannel =
-        IbcCoreChannelV1Channel.Data({
-            state: IbcCoreChannelV1GlobalEnums.State.STATE_TRYOPEN,
-            ordering: channel.ordering,
-            counterparty: expectedCounterparty,
-            connection_hops: getCounterpartyHops(channel.connection_hops[0]),
-            version: msg_.counterpartyVersion
-        });
-
-        if (
-            !verifyChannelState(
-                connection,
-                msg_.proofHeight,
-                msg_.proofTry,
-                channel.counterparty.port_id,
-                msg_.counterpartyChannelId,
-                IbcCoreChannelV1Channel.encode(expectedChannel)
-            )
-        ) {
-            revert IBCChannelLib.ErrInvalidProof();
-        }
-
-        channel.state = IbcCoreChannelV1GlobalEnums.State.STATE_OPEN;
-        channel.version = msg_.counterpartyVersion;
-        channel.counterparty.channel_id = msg_.counterpartyChannelId;
-        updateChannelCommitment(msg_.portId, msg_.channelId);
-
-        lookupModuleByPort(msg_.portId).onChanOpenAck(
-            msg_.portId,
-            msg_.channelId,
-            msg_.counterpartyChannelId,
-            msg_.counterpartyVersion,
-            msg_.relayer
-        );
-    }
-
-    /**
-     * @dev channelOpenConfirm is called by the counterparty module to close their end of the channel, since the other end has been closed.
-     */
-    function channelOpenConfirm(IBCMsgs.MsgChannelOpenConfirm calldata msg_)
-        external
-        override
-    {
-        IbcCoreChannelV1Channel.Data storage channel =
-            channels[msg_.portId][msg_.channelId];
-        if (channel.state != IbcCoreChannelV1GlobalEnums.State.STATE_TRYOPEN) {
-            revert IBCChannelLib.ErrInvalidChannelState();
-        }
-
-        emit IBCChannelLib.ChannelOpenConfirm(
-            msg_.portId,
-            msg_.channelId,
-            channel.counterparty.port_id,
-            channel.counterparty.channel_id,
-            channel.connection_hops[0]
-        );
-
-        IbcCoreConnectionV1ConnectionEnd.Data memory connection =
-            ensureConnectionState(channel.connection_hops[0]);
-
-        IbcCoreChannelV1Counterparty.Data memory expectedCounterparty =
-        IbcCoreChannelV1Counterparty.Data({
-            port_id: msg_.portId,
-            channel_id: msg_.channelId
-        });
-        IbcCoreChannelV1Channel.Data memory expectedChannel =
-        IbcCoreChannelV1Channel.Data({
-            state: IbcCoreChannelV1GlobalEnums.State.STATE_OPEN,
-            ordering: channel.ordering,
-            counterparty: expectedCounterparty,
-            connection_hops: getCounterpartyHops(channel.connection_hops[0]),
-            version: channel.version
-        });
-
-        if (
-            !verifyChannelState(
-                connection,
-                msg_.proofHeight,
-                msg_.proofAck,
-                channel.counterparty.port_id,
-                channel.counterparty.channel_id,
-                IbcCoreChannelV1Channel.encode(expectedChannel)
-            )
-        ) {
-            revert IBCChannelLib.ErrInvalidProof();
-        }
-
-        channel.state = IbcCoreChannelV1GlobalEnums.State.STATE_OPEN;
-        updateChannelCommitment(msg_.portId, msg_.channelId);
-
-        lookupModuleByPort(msg_.portId).onChanOpenConfirm(
-            msg_.portId, msg_.channelId, msg_.relayer
-        );
-    }
-
-    /**
-     * @dev channelCloseInit is called by either module to close their end of the channel. Once closed, channels cannot be reopened.
-     */
-    function channelCloseInit(IBCMsgs.MsgChannelCloseInit calldata msg_)
-        external
-        override
-    {
-        IbcCoreChannelV1Channel.Data storage channel =
-            channels[msg_.portId][msg_.channelId];
-        if (channel.state != IbcCoreChannelV1GlobalEnums.State.STATE_OPEN) {
-            revert IBCChannelLib.ErrInvalidChannelState();
-        }
-
-        ensureConnectionState(channel.connection_hops[0]);
-
-        channel.state = IbcCoreChannelV1GlobalEnums.State.STATE_CLOSED;
-        updateChannelCommitment(msg_.portId, msg_.channelId);
-
-        lookupModuleByPort(msg_.portId).onChanCloseInit(
-            msg_.portId, msg_.channelId, msg_.relayer
-        );
-
-        emit IBCChannelLib.ChannelCloseInit(msg_.channelId, msg_.portId);
-    }
-
-    /**
-     * @dev channelCloseConfirm is called by the counterparty module to close their end of the
-     * channel, since the other end has been closed.
-     */
-    function channelCloseConfirm(IBCMsgs.MsgChannelCloseConfirm calldata msg_)
-        external
-        override
-    {
-        IbcCoreChannelV1Channel.Data storage channel =
-            channels[msg_.portId][msg_.channelId];
-        if (channel.state != IbcCoreChannelV1GlobalEnums.State.STATE_OPEN) {
-            revert IBCChannelLib.ErrInvalidChannelState();
-        }
-
-        IbcCoreConnectionV1ConnectionEnd.Data memory connection =
-            ensureConnectionState(channel.connection_hops[0]);
-
-        IbcCoreChannelV1Counterparty.Data memory expectedCounterparty =
-        IbcCoreChannelV1Counterparty.Data({
-            port_id: msg_.portId,
-            channel_id: msg_.channelId
-        });
-        IbcCoreChannelV1Channel.Data memory expectedChannel =
-        IbcCoreChannelV1Channel.Data({
-            state: IbcCoreChannelV1GlobalEnums.State.STATE_CLOSED,
-            ordering: channel.ordering,
-            counterparty: expectedCounterparty,
-            connection_hops: getCounterpartyHops(channel.connection_hops[0]),
-            version: channel.version
-        });
-
-        if (
-            !verifyChannelState(
-                connection,
-                msg_.proofHeight,
-                msg_.proofInit,
-                channel.counterparty.port_id,
-                channel.counterparty.channel_id,
-                IbcCoreChannelV1Channel.encode(expectedChannel)
-            )
-        ) {
-            revert IBCChannelLib.ErrInvalidProof();
-        }
-
-        channel.state = IbcCoreChannelV1GlobalEnums.State.STATE_CLOSED;
-        updateChannelCommitment(msg_.portId, msg_.channelId);
-
-        lookupModuleByPort(msg_.portId).onChanCloseConfirm(
-            msg_.portId, msg_.channelId, msg_.relayer
-        );
-
-        emit IBCChannelLib.ChannelCloseConfirm(msg_.channelId, msg_.portId);
-    }
-
-    function updateChannelCommitment(
-        string memory portId,
-        string memory channelId
-    ) private {
-        commitments[IBCCommitment.channelCommitmentKey(portId, channelId)] =
-        keccak256(IbcCoreChannelV1Channel.encode(channels[portId][channelId]));
-    }
-
-    /* Verification functions */
-
-    function verifyChannelState(
-        IbcCoreConnectionV1ConnectionEnd.Data memory connection,
-        IbcCoreClientV1Height.Data calldata height,
-        bytes calldata proof,
-        string memory portId,
-        string memory channelId,
-        bytes memory channelBytes
-    ) private returns (bool) {
-        return getClient(connection.client_id).verifyMembership(
-            connection.client_id,
-            height,
-            0,
-            0,
-            proof,
-            connection.counterparty.prefix.key_prefix,
-            IBCCommitment.channelPath(portId, channelId),
-            channelBytes
-        );
-    }
-
-    /* Internal functions */
-
-    function getCounterpartyHops(string memory connectionId)
-        internal
-        view
-        returns (string[] memory hops)
-    {
-        hops = new string[](1);
-        hops[0] = connections[connectionId].counterparty.connection_id;
-        return hops;
-    }
-
-    function generateChannelIdentifier() internal returns (string memory) {
-        uint256 nextChannelSequence =
-            uint256(commitments[nextChannelSequencePath]);
-
-        string memory identifier = string(
-            abi.encodePacked("channel-", Strings.toString(nextChannelSequence))
-        );
-        commitments[nextChannelSequencePath] = bytes32(nextChannelSequence + 1);
-        return identifier;
-    }
-
-    function ensureConnectionState(string memory connectionId)
-        internal
-        view
-        returns (IbcCoreConnectionV1ConnectionEnd.Data memory)
-    {
-        IbcCoreConnectionV1ConnectionEnd.Data memory connection =
-            connections[connectionId];
-        if (connection.state != IbcCoreConnectionV1GlobalEnums.State.STATE_OPEN)
-        {
-            revert IBCChannelLib.ErrInvalidConnectionState();
-        }
-        return connection;
-    }
-
-    function ensureConnectionFeature(
-        string[] calldata connectionHops,
-        IbcCoreChannelV1GlobalEnums.Order ordering
-    )
-        internal
-        view
-        returns (string memory, IbcCoreConnectionV1ConnectionEnd.Data memory)
-    {
-        if (connectionHops.length != 1) {
-            revert IBCChannelLib.ErrConnNotSingleHop();
-        }
-        string memory connectionId = connectionHops[0];
-        IbcCoreConnectionV1ConnectionEnd.Data memory connection =
-            ensureConnectionState(connectionId);
-        if (connection.versions.length != 1) {
-            revert IBCChannelLib.ErrConnNotSingleVersion();
-        }
-        if (
-            !IBCChannelLib.verifySupportedFeature(
-                connection.versions[0], IBCChannelLib.toString(ordering)
-            )
-        ) {
-            revert IBCChannelLib.ErrUnsupportedFeature();
-        }
-        return (connectionId, connection);
-    }
-}
diff --git a/evm/contracts/core/04-channel/IBCPacket.sol b/evm/contracts/core/04-channel/IBCPacket.sol
index 90d76add50..fe6fa55422 100644
--- a/evm/contracts/core/04-channel/IBCPacket.sol
+++ b/evm/contracts/core/04-channel/IBCPacket.sol
@@ -1,34 +1,27 @@
 pragma solidity ^0.8.23;
 
-import "solady/utils/LibString.sol";
-import "@openzeppelin/utils/Strings.sol";
-
-import "../../proto/ibc/core/channel/v1/channel.sol";
+import "../24-host/IBCStore.sol";
 import "../25-handler/IBCMsgs.sol";
 import "../02-client/IBCHeight.sol";
 import "../24-host/IBCStore.sol";
 import "../24-host/IBCCommitment.sol";
 import "../04-channel/IIBCPacket.sol";
-import "../05-port/ModuleManager.sol";
 import "../05-port/IIBCModule.sol";
+import "../Types.sol";
 
 library IBCPacketLib {
     event SendPacket(
         uint64 sequence,
-        string sourcePort,
-        string sourceChannel,
-        IbcCoreClientV1Height.Data timeoutHeight,
+        address sourcePort,
+        uint32 sourceChannel,
+        IBCHeight timeoutHeight,
         uint64 timeoutTimestamp,
         bytes data
     );
-    event RecvPacket(IbcCoreChannelV1Packet.Data packet);
-    event WriteAcknowledgement(
-        IbcCoreChannelV1Packet.Data packet, bytes acknowledgement
-    );
-    event AcknowledgePacket(
-        IbcCoreChannelV1Packet.Data packet, bytes acknowledgement
-    );
-    event TimeoutPacket(IbcCoreChannelV1Packet.Data packet);
+    event RecvPacket(IBCPacket packet);
+    event WriteAcknowledgement(IBCPacket packet, bytes acknowledgement);
+    event AcknowledgePacket(IBCPacket packet, bytes acknowledgement);
+    event TimeoutPacket(IBCPacket packet);
 
     error ErrUnauthorized();
     error ErrInvalidChannelState();
@@ -47,7 +40,6 @@ library IBCPacketLib {
     error ErrInvalidProof();
     error ErrPacketAlreadyReceived();
     error ErrPacketSequenceNextSequenceMismatch();
-    error ErrUnknownChannelOrdering();
     error ErrAcknowledgementIsEmpty();
     error ErrAcknowledgementAlreadyExists();
     error ErrPacketCommitmentNotFound();
@@ -60,9 +52,8 @@ library IBCPacketLib {
 /**
  * @dev IBCPacket is a contract that implements [ICS-4](https://github.com/cosmos/ibc/tree/main/spec/core/ics-004-channel-and-packet-semantics).
  */
-contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
-    using IBCHeight for IbcCoreClientV1Height.Data;
-    using LibString for *;
+abstract contract IBCPacketImpl is IBCStore, IIBCPacket {
+    using IBCHeightLib for IBCHeight;
 
     /**
      * @dev sendPacket is called by a module in order to send an IBC packet on a channel.
@@ -70,84 +61,34 @@ contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
      * is returned if one occurs.
      */
     function sendPacket(
-        string calldata sourceChannel,
-        IbcCoreClientV1Height.Data calldata timeoutHeight,
+        uint32 sourceChannel,
+        IBCHeight calldata timeoutHeight,
         uint64 timeoutTimestamp,
         bytes calldata data
     ) external override returns (uint64) {
-        string memory sourcePort = msg.sender.toHexString();
-        if (
-            !authenticateCapability(
-                channelCapabilityPath(sourcePort, sourceChannel)
-            )
-        ) {
+        if (!authenticateChannelOwner(sourceChannel)) {
             revert IBCPacketLib.ErrUnauthorized();
         }
-
-        IbcCoreChannelV1Channel.Data storage channel =
-            ensureChannelState(sourcePort, sourceChannel);
-
+        ensureChannelState(sourceChannel);
         if (timeoutTimestamp == 0 && timeoutHeight.isZero()) {
             revert IBCPacketLib.ErrTimeoutMustBeSet();
         }
-
-        string memory clientId =
-            connections[channel.connection_hops[0]].client_id;
-        ILightClient client = getClient(clientId);
-
-        IbcCoreClientV1Height.Data memory latestHeight =
-            client.getLatestHeight(clientId);
-        if (latestHeight.revision_height == 0) {
-            revert IBCPacketLib.ErrLatestHeightNotFound();
-        }
-        if (!timeoutHeight.isZero() && latestHeight.gte(timeoutHeight)) {
-            revert IBCPacketLib.ErrInvalidTimeoutHeight();
-        }
-
-        uint64 latestTimestamp;
-        latestTimestamp = client.getTimestampAtHeight(clientId, latestHeight);
-        if (latestTimestamp == 0) {
-            revert IBCPacketLib.ErrLatestTimestampNotFound();
-        }
-        if (timeoutTimestamp != 0 && latestTimestamp >= timeoutTimestamp) {
-            revert IBCPacketLib.ErrInvalidTimeoutTimestamp();
-        }
-
-        uint64 packetSequence = uint64(
-            uint256(
-                commitments[IBCCommitment.nextSequenceSendCommitmentKey(
-                    sourcePort, sourceChannel
-                )]
-            )
-        );
-        commitments[IBCCommitment.nextSequenceSendCommitmentKey(
-            sourcePort, sourceChannel
-        )] = bytes32(uint256(packetSequence + 1));
+        address sourcePort = msg.sender;
+        bytes32 sourcePortNormalized = keccak256(abi.encodePacked(sourcePort));
+        uint64 sequence =
+            generatePacketSequence(sourcePortNormalized, sourceChannel);
         commitments[IBCCommitment.packetCommitmentKey(
-            sourcePort, sourceChannel, packetSequence
-        )] = keccak256(
-            abi.encodePacked(
-                sha256(
-                    abi.encodePacked(
-                        timeoutTimestamp,
-                        timeoutHeight.revision_number,
-                        timeoutHeight.revision_height,
-                        sha256(data)
-                    )
-                )
-            )
-        );
-
+            sourcePortNormalized, sourceChannel, sequence
+        )] = commitPacket(timeoutTimestamp, timeoutHeight, data);
         emit IBCPacketLib.SendPacket(
-            packetSequence,
+            sequence,
             sourcePort,
             sourceChannel,
             timeoutHeight,
             timeoutTimestamp,
             data
         );
-
-        return packetSequence;
+        return sequence;
     }
 
     /**
@@ -158,79 +99,56 @@ contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
         external
         override
     {
-        IbcCoreChannelV1Channel.Data storage channel = ensureChannelState(
-            msg_.packet.destination_port, msg_.packet.destination_channel
-        );
-
-        if (
-            hashString(msg_.packet.source_port)
-                != hashString(channel.counterparty.port_id)
-        ) {
+        IBCChannel storage channel =
+            ensureChannelState(msg_.packet.destinationChannel);
+        if (msg_.packet.sourcePort != channel.counterparty.portId) {
             revert IBCPacketLib.ErrSourceAndCounterpartyPortMismatch();
         }
-        if (
-            hashString(msg_.packet.source_channel)
-                != hashString(channel.counterparty.channel_id)
-        ) {
+        if (msg_.packet.sourceChannel != channel.counterparty.channelId) {
             revert IBCPacketLib.ErrSourceAndCounterpartyChannelMismatch();
         }
-
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection =
-            connections[channel.connection_hops[0]];
-        if (connection.state != IbcCoreConnectionV1GlobalEnums.State.STATE_OPEN)
-        {
-            revert IBCPacketLib.ErrInvalidConnectionState();
-        }
-
+        IBCConnection storage connection =
+            ensureConnectionState(channel.connectionId);
         if (
-            msg_.packet.timeout_height.revision_height != 0
-                && (block.number >= msg_.packet.timeout_height.revision_height)
+            msg_.packet.timeoutHeight.revisionHeight != 0
+                && (block.number >= msg_.packet.timeoutHeight.revisionHeight)
         ) {
             revert IBCPacketLib.ErrHeightTimeout();
         }
-
         // For some reason cosmos is using nanos, we try to follow their convention to avoid friction
         uint64 currentTimestamp = uint64(block.timestamp * 1e9);
         if (
-            msg_.packet.timeout_timestamp != 0
-                && (currentTimestamp >= msg_.packet.timeout_timestamp)
+            msg_.packet.timeoutTimestamp != 0
+                && (currentTimestamp >= msg_.packet.timeoutTimestamp)
         ) {
             revert IBCPacketLib.ErrTimestampTimeout();
         }
-
         if (
             !verifyCommitment(
                 connection,
                 msg_.proofHeight,
                 msg_.proof,
                 IBCCommitment.packetCommitmentPath(
-                    msg_.packet.source_port,
-                    msg_.packet.source_channel,
+                    msg_.packet.sourcePort,
+                    msg_.packet.sourceChannel,
                     msg_.packet.sequence
                 ),
                 abi.encodePacked(
-                    sha256(
-                        abi.encodePacked(
-                            msg_.packet.timeout_timestamp,
-                            msg_.packet.timeout_height.revision_number,
-                            msg_.packet.timeout_height.revision_height,
-                            sha256(msg_.packet.data)
-                        )
+                    commitPacket(
+                        msg_.packet.timeoutTimestamp,
+                        msg_.packet.timeoutHeight,
+                        msg_.packet.data
                     )
                 )
             )
         ) {
             revert IBCPacketLib.ErrInvalidProof();
         }
-
-        if (
-            channel.ordering
-                == IbcCoreChannelV1GlobalEnums.Order.ORDER_UNORDERED
-        ) {
+        if (channel.ordering == IBCChannelOrder.Unordered) {
             bytes32 receiptCommitmentKey = IBCCommitment
                 .packetReceiptCommitmentKey(
-                msg_.packet.destination_port,
-                msg_.packet.destination_channel,
+                msg_.packet.destinationPort,
+                msg_.packet.destinationChannel,
                 msg_.packet.sequence
             );
             bytes32 receipt = commitments[receiptCommitmentKey];
@@ -238,14 +156,12 @@ contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
                 revert IBCPacketLib.ErrPacketAlreadyReceived();
             }
             commitments[receiptCommitmentKey] = bytes32(uint256(1));
-        } else if (
-            channel.ordering == IbcCoreChannelV1GlobalEnums.Order.ORDER_ORDERED
-        ) {
+        } else if (channel.ordering == IBCChannelOrder.Ordered) {
             uint64 expectedRecvSequence = uint64(
                 uint256(
                     commitments[IBCCommitment.nextSequenceRecvCommitmentKey(
-                        msg_.packet.destination_port,
-                        msg_.packet.destination_channel
+                        msg_.packet.destinationPort,
+                        msg_.packet.destinationChannel
                     )]
                 )
             );
@@ -253,17 +169,12 @@ contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
                 revert IBCPacketLib.ErrPacketSequenceNextSequenceMismatch();
             }
             commitments[IBCCommitment.nextSequenceRecvCommitmentKey(
-                msg_.packet.destination_port, msg_.packet.destination_channel
+                msg_.packet.destinationPort, msg_.packet.destinationChannel
             )] = bytes32(uint256(expectedRecvSequence + 1));
-        } else {
-            revert IBCPacketLib.ErrUnknownChannelOrdering();
         }
-
-        IIBCModule module = lookupModuleByChannel(
-            msg_.packet.destination_port, msg_.packet.destination_channel
-        );
-        bytes memory acknowledgement =
-            module.onRecvPacket(msg_.packet, msg_.relayer);
+        bytes memory acknowledgement = lookupModuleByChannel(
+            msg_.packet.destinationChannel
+        ).onRecvPacket(msg_.packet, msg_.relayer);
         if (acknowledgement.length > 0) {
             _writeAcknowledgement(msg_.packet, acknowledgement);
         }
@@ -271,18 +182,12 @@ contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
     }
 
     function _writeAcknowledgement(
-        IbcCoreChannelV1Packet.Data calldata packet,
+        IBCPacket calldata packet,
         bytes memory acknowledgement
     ) internal {
-        if (acknowledgement.length == 0) {
-            revert IBCPacketLib.ErrAcknowledgementIsEmpty();
-        }
-
-        ensureChannelState(packet.destination_port, packet.destination_channel);
-
         bytes32 ackCommitmentKey = IBCCommitment
             .packetAcknowledgementCommitmentKey(
-            packet.destination_port, packet.destination_channel, packet.sequence
+            packet.destinationPort, packet.destinationChannel, packet.sequence
         );
         bytes32 ackCommitment = commitments[ackCommitmentKey];
         if (ackCommitment != bytes32(0)) {
@@ -290,7 +195,6 @@ contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
         }
         commitments[ackCommitmentKey] =
             keccak256(abi.encodePacked(sha256(acknowledgement)));
-
         emit IBCPacketLib.WriteAcknowledgement(packet, acknowledgement);
     }
 
@@ -299,19 +203,16 @@ contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
      * which will be verified by the counterparty chain using AcknowledgePacket.
      */
     function writeAcknowledgement(
-        IbcCoreChannelV1Packet.Data calldata packet,
+        IBCPacket calldata packet,
         bytes memory acknowledgement
     ) external override {
-        string memory destinationPort = msg.sender.toHexString();
-        if (
-            !authenticateCapability(
-                channelCapabilityPath(
-                    destinationPort, packet.destination_channel
-                )
-            )
-        ) {
+        if (acknowledgement.length == 0) {
+            revert IBCPacketLib.ErrAcknowledgementIsEmpty();
+        }
+        if (!authenticateChannelOwner(packet.destinationChannel)) {
             revert IBCPacketLib.ErrUnauthorized();
         }
+        ensureChannelState(packet.destinationChannel);
         _writeAcknowledgement(packet, acknowledgement);
     }
 
@@ -327,77 +228,38 @@ contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
         external
         override
     {
-        IbcCoreChannelV1Channel.Data storage channel = ensureChannelState(
-            msg_.packet.source_port, msg_.packet.source_channel
-        );
-
-        if (
-            hashString(msg_.packet.destination_port)
-                != hashString(channel.counterparty.port_id)
-        ) {
+        IBCChannel storage channel =
+            ensureChannelState(msg_.packet.sourceChannel);
+        if (msg_.packet.destinationPort != channel.counterparty.portId) {
             revert IBCPacketLib.ErrDestinationAndCounterpartyPortMismatch();
         }
-        if (
-            hashString(msg_.packet.destination_channel)
-                != hashString(channel.counterparty.channel_id)
-        ) {
+        if (msg_.packet.destinationChannel != channel.counterparty.channelId) {
             revert IBCPacketLib.ErrDestinationAndCounterpartyChannelMismatch();
         }
-
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection =
-            connections[channel.connection_hops[0]];
-        if (connection.state != IbcCoreConnectionV1GlobalEnums.State.STATE_OPEN)
-        {
-            revert IBCPacketLib.ErrInvalidConnectionState();
-        }
-
-        bytes32 packetCommitmentKey = IBCCommitment.packetCommitmentKey(
-            msg_.packet.source_port,
-            msg_.packet.source_channel,
-            msg_.packet.sequence
-        );
-        bytes32 expectedPacketCommitment = commitments[packetCommitmentKey];
-        if (expectedPacketCommitment == bytes32(0)) {
-            revert IBCPacketLib.ErrPacketCommitmentNotFound();
-        }
-        bytes32 packetCommitment = keccak256(
-            abi.encodePacked(
-                sha256(
-                    abi.encodePacked(
-                        msg_.packet.timeout_timestamp,
-                        msg_.packet.timeout_height.revision_number,
-                        msg_.packet.timeout_height.revision_height,
-                        sha256(msg_.packet.data)
-                    )
-                )
-            )
-        );
-        if (expectedPacketCommitment != packetCommitment) {
-            revert IBCPacketLib.ErrInvalidPacketCommitment();
-        }
-
+        IBCConnection storage connection =
+            ensureConnectionState(channel.connectionId);
+        bytes32 packetCommitmentKey = ensurePacketCommitment(msg_.packet);
+        delete commitments[packetCommitmentKey];
         if (
             !verifyCommitment(
                 connection,
                 msg_.proofHeight,
                 msg_.proof,
                 IBCCommitment.packetAcknowledgementCommitmentPath(
-                    msg_.packet.destination_port,
-                    msg_.packet.destination_channel,
+                    msg_.packet.destinationPort,
+                    msg_.packet.destinationChannel,
                     msg_.packet.sequence
                 ),
-                abi.encodePacked(sha256(msg_.acknowledgement))
+                abi.encodePacked(keccak256(msg_.acknowledgement))
             )
         ) {
             revert IBCPacketLib.ErrInvalidProof();
         }
-
-        if (channel.ordering == IbcCoreChannelV1GlobalEnums.Order.ORDER_ORDERED)
-        {
+        if (channel.ordering == IBCChannelOrder.Ordered) {
             uint64 expectedAckSequence = uint64(
                 uint256(
                     commitments[IBCCommitment.nextSequenceAckCommitmentKey(
-                        msg_.packet.source_port, msg_.packet.source_channel
+                        msg_.packet.sourcePort, msg_.packet.sourceChannel
                     )]
                 )
             );
@@ -405,104 +267,50 @@ contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
                 revert IBCPacketLib.ErrPacketSequenceNextSequenceMismatch();
             }
             commitments[IBCCommitment.nextSequenceAckCommitmentKey(
-                msg_.packet.source_port, msg_.packet.source_channel
+                msg_.packet.sourcePort, msg_.packet.sourceChannel
             )] = bytes32(uint256(expectedAckSequence + 1));
         }
-
-        delete commitments[packetCommitmentKey];
-
-        IIBCModule module = lookupModuleByChannel(
-            msg_.packet.source_port, msg_.packet.source_channel
-        );
-        module.onAcknowledgementPacket(
+        lookupModuleByChannel(msg_.packet.sourceChannel).onAcknowledgementPacket(
             msg_.packet, msg_.acknowledgement, msg_.relayer
         );
-
         emit IBCPacketLib.AcknowledgePacket(msg_.packet, msg_.acknowledgement);
     }
 
-    function hashString(string memory s) private pure returns (bytes32) {
-        return keccak256(abi.encodePacked(s));
-    }
-
     function timeoutPacket(IBCMsgs.MsgPacketTimeout calldata msg_)
         external
         override
     {
-        IbcCoreChannelV1Channel.Data storage channel = ensureChannelState(
-            msg_.packet.source_port, msg_.packet.source_channel
-        );
-
-        if (
-            hashString(msg_.packet.destination_port)
-                != hashString(channel.counterparty.port_id)
-        ) {
+        IBCChannel storage channel =
+            ensureChannelState(msg_.packet.sourceChannel);
+        if (msg_.packet.destinationPort != channel.counterparty.portId) {
             revert IBCPacketLib.ErrDestinationAndCounterpartyPortMismatch();
         }
-        if (
-            hashString(msg_.packet.destination_channel)
-                != hashString(channel.counterparty.channel_id)
-        ) {
+        if (msg_.packet.destinationChannel != channel.counterparty.channelId) {
             revert IBCPacketLib.ErrDestinationAndCounterpartyChannelMismatch();
         }
-
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection =
-            connections[channel.connection_hops[0]];
-        if (connection.state != IbcCoreConnectionV1GlobalEnums.State.STATE_OPEN)
-        {
-            revert IBCPacketLib.ErrInvalidConnectionState();
-        }
-
-        bytes32 packetCommitmentKey = IBCCommitment.packetCommitmentKey(
-            msg_.packet.source_port,
-            msg_.packet.source_channel,
-            msg_.packet.sequence
-        );
-        bytes32 expectedPacketCommitment = commitments[packetCommitmentKey];
-        if (expectedPacketCommitment == bytes32(0)) {
-            revert IBCPacketLib.ErrPacketCommitmentNotFound();
-        }
-        bytes32 packetCommitment = keccak256(
-            abi.encodePacked(
-                sha256(
-                    abi.encodePacked(
-                        msg_.packet.timeout_timestamp,
-                        msg_.packet.timeout_height.revision_number,
-                        msg_.packet.timeout_height.revision_height,
-                        sha256(msg_.packet.data)
-                    )
-                )
-            )
-        );
-        if (expectedPacketCommitment != packetCommitment) {
-            revert IBCPacketLib.ErrInvalidPacketCommitment();
-        }
-
-        ILightClient client = getClient(connection.client_id);
+        IBCConnection storage connection =
+            ensureConnectionState(channel.connectionId);
+        bytes32 packetCommitmentKey = ensurePacketCommitment(msg_.packet);
+        delete commitments[packetCommitmentKey];
+        ILightClient client = getClientInternal(connection.clientId);
         uint64 proofTimestamp =
-            client.getTimestampAtHeight(connection.client_id, msg_.proofHeight);
+            client.getTimestampAtHeight(connection.clientId, msg_.proofHeight);
         if (proofTimestamp == 0) {
             revert IBCPacketLib.ErrLatestTimestampNotFound();
         }
-
         if (
-            msg_.packet.timeout_timestamp > 0
-                && msg_.packet.timeout_timestamp >= proofTimestamp
+            msg_.packet.timeoutTimestamp > 0
+                && msg_.packet.timeoutTimestamp >= proofTimestamp
         ) {
             revert IBCPacketLib.ErrTimeoutTimestampNotReached();
         }
         if (
-            !msg_.packet.timeout_height.isZero()
-                && msg_.packet.timeout_height.gte(msg_.proofHeight)
+            !msg_.packet.timeoutHeight.isZero()
+                && msg_.packet.timeoutHeight.gte(msg_.proofHeight)
         ) {
             revert IBCPacketLib.ErrTimeoutHeightNotReached();
         }
-
-        bool isOrdered =
-            channel.ordering == IbcCoreChannelV1GlobalEnums.Order.ORDER_ORDERED;
-        bool isUnordered = channel.ordering
-            == IbcCoreChannelV1GlobalEnums.Order.ORDER_UNORDERED;
-        if (isOrdered) {
+        if (channel.ordering == IBCChannelOrder.Ordered) {
             if (msg_.nextSequenceRecv <= msg_.packet.sequence) {
                 revert
                     IBCPacketLib
@@ -514,89 +322,134 @@ contract IBCPacket is IBCStore, IIBCPacket, ModuleManager {
                     msg_.proofHeight,
                     msg_.proof,
                     IBCCommitment.nextSequenceRecvCommitmentPath(
-                        msg_.packet.destination_port,
-                        msg_.packet.destination_channel
+                        msg_.packet.destinationPort,
+                        msg_.packet.destinationChannel
                     ),
                     abi.encodePacked(msg_.nextSequenceRecv)
                 )
             ) {
                 revert IBCPacketLib.ErrInvalidProof();
             }
-            channel.state = IbcCoreChannelV1GlobalEnums.State.STATE_CLOSED;
-        } else if (isUnordered) {
+        } else if (channel.ordering == IBCChannelOrder.Unordered) {
             if (
                 !verifyAbsentCommitment(
                     connection,
                     msg_.proofHeight,
                     msg_.proof,
                     IBCCommitment.packetReceiptCommitmentPath(
-                        msg_.packet.destination_port,
-                        msg_.packet.destination_channel,
+                        msg_.packet.destinationPort,
+                        msg_.packet.destinationChannel,
                         msg_.packet.sequence
                     )
                 )
             ) {
                 revert IBCPacketLib.ErrInvalidProof();
             }
-        } else {
-            revert IBCPacketLib.ErrUnknownChannelOrdering();
         }
-
-        delete commitments[packetCommitmentKey];
-
-        IIBCModule module = lookupModuleByChannel(
-            msg_.packet.source_port, msg_.packet.source_channel
+        lookupModuleByChannel(msg_.packet.sourceChannel).onTimeoutPacket(
+            msg_.packet, msg_.relayer
         );
-        module.onTimeoutPacket(msg_.packet, msg_.relayer);
-
         emit IBCPacketLib.TimeoutPacket(msg_.packet);
     }
 
     function verifyCommitment(
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection,
-        IbcCoreClientV1Height.Data calldata height,
+        IBCConnection storage connection,
+        IBCHeight calldata height,
         bytes calldata proof,
         bytes memory path,
         bytes memory commitment
-    ) private returns (bool) {
-        return getClient(connection.client_id).verifyMembership(
-            connection.client_id,
+    ) internal returns (bool) {
+        return getClientInternal(connection.clientId).verifyMembership(
+            connection.clientId,
             height,
-            connection.delay_period,
+            connection.delayPeriod,
             0,
             proof,
-            connection.counterparty.prefix.key_prefix,
+            abi.encodePacked(connection.counterparty.merklePrefix),
             path,
             commitment
         );
     }
 
     function verifyAbsentCommitment(
-        IbcCoreConnectionV1ConnectionEnd.Data storage connection,
-        IbcCoreClientV1Height.Data calldata height,
+        IBCConnection storage connection,
+        IBCHeight calldata height,
         bytes calldata proof,
         bytes memory path
-    ) private returns (bool) {
-        return getClient(connection.client_id).verifyNonMembership(
-            connection.client_id,
+    ) internal returns (bool) {
+        return getClientInternal(connection.clientId).verifyNonMembership(
+            connection.clientId,
             height,
-            connection.delay_period,
+            connection.delayPeriod,
             0,
             proof,
-            connection.counterparty.prefix.key_prefix,
+            abi.encodePacked(connection.counterparty.merklePrefix),
             path
         );
     }
 
-    function ensureChannelState(
-        string memory portId,
-        string calldata channelId
-    ) internal view returns (IbcCoreChannelV1Channel.Data storage) {
-        IbcCoreChannelV1Channel.Data storage channel =
-            channels[portId][channelId];
-        if (channel.state != IbcCoreChannelV1GlobalEnums.State.STATE_OPEN) {
+    function ensureChannelState(uint32 channelId)
+        internal
+        view
+        returns (IBCChannel storage)
+    {
+        IBCChannel storage channel = channels[channelId];
+        if (channel.state != IBCChannelState.Open) {
             revert IBCPacketLib.ErrInvalidChannelState();
         }
         return channel;
     }
+
+    function generatePacketSequence(
+        bytes32 portId,
+        uint32 channelId
+    ) internal returns (uint64) {
+        uint64 seq = uint64(
+            uint256(
+                commitments[IBCCommitment.nextSequenceSendCommitmentKey(
+                    portId, channelId
+                )]
+            )
+        );
+        commitments[IBCCommitment.nextSequenceSendCommitmentKey(
+            portId, channelId
+        )] = bytes32(uint256(seq + 1));
+        return seq;
+    }
+
+    function ensurePacketCommitment(IBCPacket calldata packet)
+        internal
+        view
+        returns (bytes32)
+    {
+        bytes32 packetCommitmentKey = IBCCommitment.packetCommitmentKey(
+            packet.sourcePort, packet.sourceChannel, packet.sequence
+        );
+        bytes32 expectedPacketCommitment = commitments[packetCommitmentKey];
+        if (expectedPacketCommitment == bytes32(0)) {
+            revert IBCPacketLib.ErrPacketCommitmentNotFound();
+        }
+        bytes32 packetCommitment = commitPacket(
+            packet.timeoutTimestamp, packet.timeoutHeight, packet.data
+        );
+        if (expectedPacketCommitment != packetCommitment) {
+            revert IBCPacketLib.ErrInvalidPacketCommitment();
+        }
+        return packetCommitmentKey;
+    }
+
+    function commitPacket(
+        uint64 timeoutTimestamp,
+        IBCHeight calldata timeoutHeight,
+        bytes calldata data
+    ) internal pure returns (bytes32) {
+        return keccak256(
+            abi.encodePacked(
+                timeoutTimestamp,
+                timeoutHeight.revisionNumber,
+                timeoutHeight.revisionHeight,
+                data
+            )
+        );
+    }
 }
diff --git a/evm/contracts/core/04-channel/IIBCChannel.sol b/evm/contracts/core/04-channel/IIBCChannel.sol
index 970b3eeee8..22e982fc45 100644
--- a/evm/contracts/core/04-channel/IIBCChannel.sol
+++ b/evm/contracts/core/04-channel/IIBCChannel.sol
@@ -2,20 +2,20 @@ pragma solidity ^0.8.23;
 
 import "../25-handler/IBCMsgs.sol";
 
-interface IIBCChannelHandshake {
+interface IIBCChannel {
     /**
      * @dev channelOpenInit is called by a module to initiate a channel opening handshake with a module on another chain.
      */
     function channelOpenInit(IBCMsgs.MsgChannelOpenInit calldata msg_)
         external
-        returns (string memory);
+        returns (uint32);
 
     /**
      * @dev channelOpenTry is called by a module to accept the first step of a channel opening handshake initiated by a module on another chain.
      */
     function channelOpenTry(IBCMsgs.MsgChannelOpenTry calldata msg_)
         external
-        returns (string memory);
+        returns (uint32);
 
     /**
      * @dev channelOpenAck is called by the handshake-originating module to acknowledge the acceptance of the initial request by the counterparty module on the other chain.
diff --git a/evm/contracts/core/04-channel/IIBCPacket.sol b/evm/contracts/core/04-channel/IIBCPacket.sol
index c0f336d4a3..efad804be5 100644
--- a/evm/contracts/core/04-channel/IIBCPacket.sol
+++ b/evm/contracts/core/04-channel/IIBCPacket.sol
@@ -9,8 +9,8 @@ interface IIBCPacket {
      * is returned if one occurs.
      */
     function sendPacket(
-        string calldata sourceChannel,
-        IbcCoreClientV1Height.Data calldata timeoutHeight,
+        uint32 sourceChannel,
+        IBCHeight calldata timeoutHeight,
         uint64 timeoutTimestamp,
         bytes calldata data
     ) external returns (uint64);
@@ -26,7 +26,7 @@ interface IIBCPacket {
      * which will be verified by the counterparty chain using AcknowledgePacket.
      */
     function writeAcknowledgement(
-        IbcCoreChannelV1Packet.Data calldata packet,
+        IBCPacket calldata packet,
         bytes memory acknowledgement
     ) external;
 
diff --git a/evm/contracts/core/05-port/IIBCModule.sol b/evm/contracts/core/05-port/IIBCModule.sol
index b771206156..d8d98a5964 100644
--- a/evm/contracts/core/05-port/IIBCModule.sol
+++ b/evm/contracts/core/05-port/IIBCModule.sol
@@ -1,71 +1,53 @@
 pragma solidity ^0.8.23;
 
-import "../../proto/ibc/core/channel/v1/channel.sol";
+import "../Types.sol";
 
 // IIBCModule defines an interface that implements all the callbacks
 // that modules must define as specified in ICS-26
 // https://github.com/cosmos/ibc/blob/2921c5cec7b18e4ef77677e16a6b693051ae3b35/spec/core/ics-026-routing-module/README.md
 interface IIBCModule {
     function onChanOpenInit(
-        IbcCoreChannelV1GlobalEnums.Order,
-        string[] calldata connectionHops,
-        string calldata portId,
-        string calldata channelId,
-        IbcCoreChannelV1Counterparty.Data calldata counterparty,
-        string calldata version,
+        IBCChannelOrder,
+        uint32 connectionId,
+        uint32 channelId,
+        IBCChannelCounterparty calldata counterparty,
+        bytes32 version,
         address relayer
     ) external;
 
     function onChanOpenTry(
-        IbcCoreChannelV1GlobalEnums.Order,
-        string[] calldata connectionHops,
-        string calldata portId,
-        string calldata channelId,
-        IbcCoreChannelV1Counterparty.Data calldata counterparty,
-        string calldata version,
-        string calldata counterpartyVersion,
+        IBCChannelOrder,
+        uint32 connectionId,
+        uint32 channelId,
+        IBCChannelCounterparty calldata counterparty,
+        bytes32 version,
+        bytes32 counterpartyVersion,
         address relayer
     ) external;
 
     function onChanOpenAck(
-        string calldata portId,
-        string calldata channelId,
-        string calldata counterpartyChannelId,
-        string calldata counterpartyVersion,
+        uint32 channelId,
+        uint32 counterpartyChannelId,
+        bytes32 counterpartyVersion,
         address relayer
     ) external;
 
-    function onChanOpenConfirm(
-        string calldata portId,
-        string calldata channelId,
-        address relayer
-    ) external;
+    function onChanOpenConfirm(uint32 channelId, address relayer) external;
 
-    function onChanCloseInit(
-        string calldata portId,
-        string calldata channelId,
-        address relayer
-    ) external;
+    function onChanCloseInit(uint32 channelId, address relayer) external;
 
-    function onChanCloseConfirm(
-        string calldata portId,
-        string calldata channelId,
-        address relayer
-    ) external;
+    function onChanCloseConfirm(uint32 channelId, address relayer) external;
 
     function onRecvPacket(
-        IbcCoreChannelV1Packet.Data calldata,
+        IBCPacket calldata,
         address relayer
     ) external returns (bytes memory);
 
     function onAcknowledgementPacket(
-        IbcCoreChannelV1Packet.Data calldata,
+        IBCPacket calldata,
         bytes calldata acknowledgement,
         address relayer
     ) external;
 
-    function onTimeoutPacket(
-        IbcCoreChannelV1Packet.Data calldata,
-        address relayer
-    ) external;
+    function onTimeoutPacket(IBCPacket calldata, address relayer) external;
 }
diff --git a/evm/contracts/core/05-port/ModuleManager.sol b/evm/contracts/core/05-port/ModuleManager.sol
deleted file mode 100644
index a1fb80bb8f..0000000000
--- a/evm/contracts/core/05-port/ModuleManager.sol
+++ /dev/null
@@ -1,80 +0,0 @@
-pragma solidity ^0.8.23;
-
-import "./IIBCModule.sol";
-import "../24-host/IBCStore.sol";
-import "../../lib/Hex.sol";
-
-library ModuleManagerLib {
-    error ErrModuleNotFound();
-    error ErrCapabilityAlreadyClaimed();
-}
-
-/**
- * @dev ModuleManager is an abstract contract that provides the functions defined in [ICS 5](https://github.com/cosmos/ibc/tree/main/spec/core/ics-005-port-allocation) and [ICS 26](https://github.com/cosmos/ibc/blob/main/spec/core/ics-005-port-module/README.md).
- */
-abstract contract ModuleManager is IBCStore {
-    /**
-     * @dev lookupModuleByPort will return the IBCModule along with the capability associated with a given portID
-     */
-    function lookupModuleByPort(string memory portId)
-        internal
-        view
-        virtual
-        returns (IIBCModule)
-    {
-        return IIBCModule(Hex.hexToAddress(portId));
-    }
-
-    /**
-     * @dev lookupModuleByChannel will return the IBCModule along with the capability associated with a given channel defined by its portID and channelID
-     */
-    function lookupModuleByChannel(
-        string memory portId,
-        string memory channelId
-    ) internal view virtual returns (IIBCModule) {
-        address module = lookupModule(channelCapabilityPath(portId, channelId));
-        if (module == address(0)) {
-            revert ModuleManagerLib.ErrModuleNotFound();
-        }
-        return IIBCModule(module);
-    }
-
-    /**
-     * @dev channelCapabilityPath returns the path under which module address associated with a port and channel should be stored.
-     */
-    function channelCapabilityPath(
-        string memory portId,
-        string memory channelId
-    ) public pure returns (string memory) {
-        return string.concat(portId, "/", channelId);
-    }
-
-    /**
-     * @dev claimCapability allows the IBC app module to claim a capability that core IBC passes to it
-     */
-    function claimCapability(string memory name, address addr) internal {
-        if (capabilities[name] != address(0)) {
-            revert ModuleManagerLib.ErrCapabilityAlreadyClaimed();
-        }
-        capabilities[name] = addr;
-    }
-
-    /**
-     * @dev authenticateCapability attempts to authenticate a given name from a caller.
-     * It allows for a caller to check that a capability does in fact correspond to a particular name.
-     */
-    function authenticateCapability(string memory name)
-        internal
-        view
-        returns (bool)
-    {
-        return msg.sender == capabilities[name];
-    }
-
-    /**
-     * @dev lookupModule will return the IBCModule address bound to a given name.
-     */
-    function lookupModule(string memory name) internal view returns (address) {
-        return capabilities[name];
-    }
-}
diff --git a/evm/contracts/core/24-host/IBCCommitment.sol b/evm/contracts/core/24-host/IBCCommitment.sol
index e7f880c980..419e5fb2fc 100644
--- a/evm/contracts/core/24-host/IBCCommitment.sol
+++ b/evm/contracts/core/24-host/IBCCommitment.sol
@@ -3,123 +3,98 @@ pragma solidity ^0.8.23;
 import "solady/utils/LibString.sol";
 
 library IBCCommitment {
-    // Commitment path generators that comply with https://github.com/cosmos/ibc/tree/main/spec/core/ics-024-host-requirements#path-space
-
-    function clientStatePath(string memory clientId)
+    bytes1 public constant CLIENT_STATE = 0x00;
+    bytes1 public constant CONSENSUS_STATE = 0x01;
+    bytes1 public constant CONNECTIONS = 0x02;
+    bytes1 public constant CHANNELS = 0x05;
+    bytes1 public constant PACKETS = 0x06;
+    bytes1 public constant PACKET_ACKS = 0x07;
+    bytes1 public constant PACKET_RECEIPTS = 0x08;
+    bytes1 public constant NEXT_SEQ_SEND = 0x09;
+    bytes1 public constant NEXT_SEQ_RECV = 0x0A;
+    bytes1 public constant NEXT_SEQ_ACK = 0x0B;
+
+    function clientStatePath(uint32 clientId)
         internal
         pure
         returns (bytes memory)
     {
-        return abi.encodePacked("clients/", clientId, "/clientState");
+        return abi.encodePacked(CLIENT_STATE, clientId);
     }
 
     function consensusStatePath(
-        string memory clientId,
+        uint32 clientId,
         uint64 revisionNumber,
         uint64 revisionHeight
     ) internal pure returns (bytes memory) {
         return abi.encodePacked(
-            "clients/",
-            clientId,
-            "/consensusStates/",
-            LibString.toString(revisionNumber),
-            "-",
-            LibString.toString(revisionHeight)
+            CONSENSUS_STATE, clientId, revisionNumber, revisionHeight
         );
     }
 
-    function connectionPath(string memory connectionId)
+    function connectionPath(uint32 connectionId)
         internal
         pure
         returns (bytes memory)
     {
-        return abi.encodePacked("connections/", connectionId);
+        return abi.encodePacked(CONNECTIONS, connectionId);
     }
 
     function channelPath(
-        string memory portId,
-        string memory channelId
+        bytes32 portId,
+        uint32 channelId
     ) internal pure returns (bytes memory) {
-        return abi.encodePacked(
-            "channelEnds/ports/", portId, "/channels/", channelId
-        );
+        return abi.encodePacked(CHANNELS, portId, channelId);
     }
 
     function packetCommitmentPath(
-        string memory portId,
-        string memory channelId,
+        bytes32 portId,
+        uint32 channelId,
         uint64 sequence
     ) internal pure returns (bytes memory) {
-        return abi.encodePacked(
-            "commitments/ports/",
-            portId,
-            "/channels/",
-            channelId,
-            "/sequences/",
-            LibString.toString(sequence)
-        );
+        return abi.encodePacked(PACKETS, portId, channelId, sequence);
     }
 
     function packetAcknowledgementCommitmentPath(
-        string memory portId,
-        string memory channelId,
+        bytes32 portId,
+        uint32 channelId,
         uint64 sequence
     ) internal pure returns (bytes memory) {
-        return abi.encodePacked(
-            "acks/ports/",
-            portId,
-            "/channels/",
-            channelId,
-            "/sequences/",
-            LibString.toString(sequence)
-        );
+        return abi.encodePacked(PACKET_ACKS, portId, channelId, sequence);
     }
 
     function packetReceiptCommitmentPath(
-        string memory portId,
-        string memory channelId,
+        bytes32 portId,
+        uint32 channelId,
         uint64 sequence
     ) internal pure returns (bytes memory) {
-        return abi.encodePacked(
-            "receipts/ports/",
-            portId,
-            "/channels/",
-            channelId,
-            "/sequences/",
-            LibString.toString(sequence)
-        );
+        return abi.encodePacked(PACKET_RECEIPTS, portId, channelId, sequence);
     }
 
     function nextSequenceSendCommitmentPath(
-        string memory portId,
-        string memory channelId
+        bytes32 portId,
+        uint32 channelId
     ) internal pure returns (bytes memory) {
-        return abi.encodePacked(
-            "nextSequenceSend/ports/", portId, "/channels/", channelId
-        );
+        return abi.encodePacked(NEXT_SEQ_SEND, portId, channelId);
     }
 
     function nextSequenceRecvCommitmentPath(
-        string memory portId,
-        string memory channelId
+        bytes32 portId,
+        uint32 channelId
     ) internal pure returns (bytes memory) {
-        return abi.encodePacked(
-            "nextSequenceRecv/ports/", portId, "/channels/", channelId
-        );
+        return abi.encodePacked(NEXT_SEQ_RECV, portId, channelId);
     }
 
     function nextSequenceAckCommitmentPath(
-        string memory portId,
-        string memory channelId
+        bytes32 portId,
+        uint32 channelId
     ) internal pure returns (bytes memory) {
-        return abi.encodePacked(
-            "nextSequenceAck/ports/", portId, "/channels/", channelId
-        );
+        return abi.encodePacked(NEXT_SEQ_ACK, portId, channelId);
     }
 
     // Key generators for Commitment mapping
 
-    function clientStateCommitmentKey(string memory clientId)
+    function clientStateCommitmentKey(uint32 clientId)
         internal
         pure
         returns (bytes32)
@@ -128,7 +103,7 @@ library IBCCommitment {
     }
 
     function consensusStateCommitmentKey(
-        string memory clientId,
+        uint32 clientId,
         uint64 revisionNumber,
         uint64 revisionHeight
     ) internal pure returns (bytes32) {
@@ -137,7 +112,7 @@ library IBCCommitment {
         );
     }
 
-    function connectionCommitmentKey(string memory connectionId)
+    function connectionCommitmentKey(uint32 connectionId)
         internal
         pure
         returns (bytes32)
@@ -146,23 +121,23 @@ library IBCCommitment {
     }
 
     function channelCommitmentKey(
-        string memory portId,
-        string memory channelId
+        bytes32 portId,
+        uint32 channelId
     ) internal pure returns (bytes32) {
         return keccak256(channelPath(portId, channelId));
     }
 
     function packetCommitmentKey(
-        string memory portId,
-        string memory channelId,
+        bytes32 portId,
+        uint32 channelId,
         uint64 sequence
     ) internal pure returns (bytes32) {
         return keccak256(packetCommitmentPath(portId, channelId, sequence));
     }
 
     function packetAcknowledgementCommitmentKey(
-        string memory portId,
-        string memory channelId,
+        bytes32 portId,
+        uint32 channelId,
         uint64 sequence
     ) internal pure returns (bytes32) {
         return keccak256(
@@ -171,8 +146,8 @@ library IBCCommitment {
     }
 
     function packetReceiptCommitmentKey(
-        string memory portId,
-        string memory channelId,
+        bytes32 portId,
+        uint32 channelId,
         uint64 sequence
     ) internal pure returns (bytes32) {
         return
@@ -180,22 +155,22 @@ library IBCCommitment {
     }
 
     function nextSequenceSendCommitmentKey(
-        string memory portId,
-        string memory channelId
+        bytes32 portId,
+        uint32 channelId
     ) internal pure returns (bytes32) {
         return keccak256(nextSequenceSendCommitmentPath(portId, channelId));
     }
 
     function nextSequenceRecvCommitmentKey(
-        string memory portId,
-        string memory channelId
+        bytes32 portId,
+        uint32 channelId
     ) internal pure returns (bytes32) {
         return keccak256(nextSequenceRecvCommitmentPath(portId, channelId));
     }
 
     function nextSequenceAckCommitmentKey(
-        string memory portId,
-        string memory channelId
+        bytes32 portId,
+        uint32 channelId
     ) internal pure returns (bytes32) {
         return keccak256(nextSequenceAckCommitmentPath(portId, channelId));
     }
diff --git a/evm/contracts/core/24-host/IBCHost.sol b/evm/contracts/core/24-host/IBCHost.sol
deleted file mode 100644
index 65ae7808ab..0000000000
--- a/evm/contracts/core/24-host/IBCHost.sol
+++ /dev/null
@@ -1,24 +0,0 @@
-pragma solidity ^0.8.23;
-
-import "@openzeppelin/utils/Context.sol";
-import "../../proto/ibc/core/client/v1/client.sol";
-import "../02-client/ILightClient.sol";
-import "../24-host/IBCStore.sol";
-import "../05-port/ModuleManager.sol";
-
-function passthrough(address impl) {
-    assembly {
-        // copy function selector and any arguments
-        calldatacopy(0, 0, calldatasize())
-        // execute function call using the facet
-        let result := delegatecall(gas(), impl, 0, calldatasize(), 0, 0)
-        // get any return value
-        returndatacopy(0, 0, returndatasize())
-        // return any return value or error back to the caller
-        switch result
-        case 0 { revert(0, returndatasize()) }
-        default { return(0, returndatasize()) }
-    }
-}
-
-abstract contract IBCHost is ModuleManager {}
diff --git a/evm/contracts/core/24-host/IBCStore.sol b/evm/contracts/core/24-host/IBCStore.sol
index 1a53bfd10e..60dbc79043 100644
--- a/evm/contracts/core/24-host/IBCStore.sol
+++ b/evm/contracts/core/24-host/IBCStore.sol
@@ -1,28 +1,36 @@
 pragma solidity ^0.8.23;
 
-import "../../proto/ibc/core/connection/v1/connection.sol";
-import "../../proto/ibc/core/channel/v1/channel.sol";
 import "../02-client/ILightClient.sol";
+import "../05-port/IIBCModule.sol";
+import "../Types.sol";
 
 library IBCStoreLib {
-    string public constant COMMITMENT_PREFIX = "ibc";
+    bytes32 public constant COMMITMENT_PREFIX = keccak256("ethibc");
 
     error ErrClientNotFound();
+    error ErrModuleNotFound();
+    error ErrInvalidConnectionState();
 }
 
 abstract contract IBCStore {
+    bytes32 public constant COMMITMENT_PREFIX = IBCStoreLib.COMMITMENT_PREFIX;
+
     // Commitments
     // keccak256(IBC-compatible-store-path) => keccak256(IBC-compatible-commitment)
-    mapping(bytes32 => bytes32) public commitments;
+    mapping(bytes32 => bytes32) internal commitments;
 
-    // Store
-    mapping(string => address) public clientRegistry;
-    mapping(string => string) public clientTypes;
-    mapping(string => address) public clientImpls;
-    mapping(string => IbcCoreConnectionV1ConnectionEnd.Data) public connections;
-    mapping(string => mapping(string => IbcCoreChannelV1Channel.Data)) public
-        channels;
-    mapping(string => address) public capabilities;
+    // ClientType -> Address
+    mapping(bytes32 => address) internal clientRegistry;
+    // ClientId -> ClientType
+    mapping(uint32 => bytes32) internal clientTypes;
+    // ClientId -> Address
+    mapping(uint32 => address) internal clientImpls;
+    // ConnectionId -> Connection
+    mapping(uint32 => IBCConnection) internal connections;
+    // ChannelId -> Channel
+    mapping(uint32 => IBCChannel) internal channels;
+    // ChannelId -> PortId
+    mapping(uint32 => address) internal channelOwner;
 
     // Sequences for identifier
     bytes32 public constant nextClientSequencePath =
@@ -32,11 +40,12 @@ abstract contract IBCStore {
     bytes32 public constant nextChannelSequencePath =
         keccak256("nextChannelSequence");
 
-    string public constant COMMITMENT_PREFIX = IBCStoreLib.COMMITMENT_PREFIX;
+    function getClient(uint32 clientId) public view returns (ILightClient) {
+        return getClientInternal(clientId);
+    }
 
-    // Storage accessors
-    function getClient(string memory clientId)
-        public
+    function getClientInternal(uint32 clientId)
+        internal
         view
         returns (ILightClient)
     {
@@ -46,4 +55,41 @@ abstract contract IBCStore {
         }
         return ILightClient(clientImpl);
     }
+
+    function lookupModuleByChannel(uint32 channelId)
+        internal
+        view
+        virtual
+        returns (IIBCModule)
+    {
+        address module = channelOwner[channelId];
+        if (module == address(0)) {
+            revert IBCStoreLib.ErrModuleNotFound();
+        }
+        return IIBCModule(module);
+    }
+
+    function claimChannel(address portId, uint32 channelId) internal {
+        channelOwner[channelId] = portId;
+    }
+
+    function authenticateChannelOwner(uint32 channelId)
+        internal
+        view
+        returns (bool)
+    {
+        return msg.sender == channelOwner[channelId];
+    }
+
+    function ensureConnectionState(uint32 connectionId)
+        internal
+        view
+        returns (IBCConnection storage)
+    {
+        IBCConnection storage connection = connections[connectionId];
+        if (connection.state != IBCConnectionState.Open) {
+            revert IBCStoreLib.ErrInvalidConnectionState();
+        }
+        return connection;
+    }
 }
diff --git a/evm/contracts/core/25-handler/IBCChannelHandler.sol b/evm/contracts/core/25-handler/IBCChannelHandler.sol
deleted file mode 100644
index 64ddb6d079..0000000000
--- a/evm/contracts/core/25-handler/IBCChannelHandler.sol
+++ /dev/null
@@ -1,58 +0,0 @@
-pragma solidity ^0.8.23;
-
-import "../25-handler/IBCMsgs.sol";
-import "../24-host/IBCHost.sol";
-import "../04-channel/IIBCChannel.sol";
-import "../05-port/IIBCModule.sol";
-import "../05-port/ModuleManager.sol";
-
-/**
- * @dev IBCChannelHandler is a contract that calls a contract that implements `IIBCChannelHandshake` with delegatecall.
- */
-abstract contract IBCChannelHandler is IIBCChannelHandshake {
-    address ibcChannel;
-
-    function channelOpenInit(IBCMsgs.MsgChannelOpenInit calldata)
-        external
-        override
-        returns (string memory)
-    {
-        passthrough(ibcChannel);
-    }
-
-    function channelOpenTry(IBCMsgs.MsgChannelOpenTry calldata)
-        external
-        override
-        returns (string memory)
-    {
-        passthrough(ibcChannel);
-    }
-
-    function channelOpenAck(IBCMsgs.MsgChannelOpenAck calldata)
-        external
-        override
-    {
-        passthrough(ibcChannel);
-    }
-
-    function channelOpenConfirm(IBCMsgs.MsgChannelOpenConfirm calldata)
-        external
-        override
-    {
-        passthrough(ibcChannel);
-    }
-
-    function channelCloseInit(IBCMsgs.MsgChannelCloseInit calldata)
-        external
-        override
-    {
-        passthrough(ibcChannel);
-    }
-
-    function channelCloseConfirm(IBCMsgs.MsgChannelCloseConfirm calldata)
-        external
-        override
-    {
-        passthrough(ibcChannel);
-    }
-}
diff --git a/evm/contracts/core/25-handler/IBCClientHandler.sol b/evm/contracts/core/25-handler/IBCClientHandler.sol
deleted file mode 100644
index b8fead9be0..0000000000
--- a/evm/contracts/core/25-handler/IBCClientHandler.sol
+++ /dev/null
@@ -1,36 +0,0 @@
-pragma solidity ^0.8.23;
-
-import "../24-host/IBCHost.sol";
-import "../02-client/IIBCClient.sol";
-
-/**
- * @dev IBCClientHandler is a contract that calls a contract that implements `IIBCClient` with delegatecall.
- */
-abstract contract IBCClientHandler is IIBCClient {
-    address ibcClient;
-
-    /**
-     * @dev registerClient registers a new client type into the client registry
-     */
-    function registerClient(string calldata, ILightClient) public virtual {
-        passthrough(ibcClient);
-    }
-
-    /**
-     * @dev createClient creates a new client state and populates it with a given consensus state
-     */
-    function createClient(IBCMsgs.MsgCreateClient calldata)
-        external
-        override
-        returns (string memory)
-    {
-        passthrough(ibcClient);
-    }
-
-    /**
-     * @dev updateClient updates the consensus state and the state root from a provided header
-     */
-    function updateClient(IBCMsgs.MsgUpdateClient calldata) external override {
-        passthrough(ibcClient);
-    }
-}
diff --git a/evm/contracts/core/25-handler/IBCConnectionHandler.sol b/evm/contracts/core/25-handler/IBCConnectionHandler.sol
deleted file mode 100644
index a584f444f7..0000000000
--- a/evm/contracts/core/25-handler/IBCConnectionHandler.sol
+++ /dev/null
@@ -1,42 +0,0 @@
-pragma solidity ^0.8.23;
-
-import "../25-handler/IBCMsgs.sol";
-import "../24-host/IBCHost.sol";
-import "../03-connection/IIBCConnection.sol";
-
-/**
- * @dev IBCConnectionHandler is a contract that calls a contract that implements `IIBCConnectionHandshake` with delegatecall.
- */
-abstract contract IBCConnectionHandler is IIBCConnectionHandshake {
-    address ibcConnection;
-
-    function connectionOpenInit(IBCMsgs.MsgConnectionOpenInit calldata)
-        external
-        override
-        returns (string memory)
-    {
-        passthrough(ibcConnection);
-    }
-
-    function connectionOpenTry(IBCMsgs.MsgConnectionOpenTry calldata)
-        external
-        override
-        returns (string memory)
-    {
-        passthrough(ibcConnection);
-    }
-
-    function connectionOpenAck(IBCMsgs.MsgConnectionOpenAck calldata)
-        external
-        override
-    {
-        passthrough(ibcConnection);
-    }
-
-    function connectionOpenConfirm(IBCMsgs.MsgConnectionOpenConfirm calldata)
-        external
-        override
-    {
-        passthrough(ibcConnection);
-    }
-}
diff --git a/evm/contracts/core/25-handler/IBCHandler.sol b/evm/contracts/core/25-handler/IBCHandler.sol
index 86fb5bf05e..fc584116cd 100644
--- a/evm/contracts/core/25-handler/IBCHandler.sol
+++ b/evm/contracts/core/25-handler/IBCHandler.sol
@@ -1,16 +1,14 @@
 pragma solidity ^0.8.23;
 
-import "../24-host/IBCHost.sol";
-import "./IBCClientHandler.sol";
-import "./IBCConnectionHandler.sol";
-import "./IBCChannelHandler.sol";
-import "./IBCPacketHandler.sol";
-import "./IBCQuerier.sol";
+import "../24-host/IBCStore.sol";
+import "../02-client/IBCClient.sol";
+import "../03-connection/IBCConnection.sol";
+import "../04-channel/IBCChannel.sol";
+import "../04-channel/IBCPacket.sol";
 
 import "@openzeppelin-upgradeable/proxy/utils/Initializable.sol";
 import "@openzeppelin-upgradeable/proxy/utils/UUPSUpgradeable.sol";
 import "@openzeppelin-upgradeable/access/OwnableUpgradeable.sol";
-import "@openzeppelin-upgradeable/utils/PausableUpgradeable.sol";
 import "@openzeppelin-upgradeable/utils/ContextUpgradeable.sol";
 import "@openzeppelin/utils/Context.sol";
 
@@ -21,38 +19,19 @@ abstract contract IBCHandler is
     Initializable,
     UUPSUpgradeable,
     OwnableUpgradeable,
-    PausableUpgradeable,
-    IBCHost,
-    IBCClientHandler,
-    IBCConnectionHandler,
-    IBCChannelHandler,
-    IBCPacketHandler,
-    IBCQuerier
+    IBCStore,
+    IBCClient,
+    IBCConnectionImpl,
+    IBCChannelImpl,
+    IBCPacketImpl
 {
     constructor() {
         _disableInitializers();
     }
 
-    /**
-     * @dev The arguments of constructor must satisfy the followings:
-     * @param _ibcClient is the address of a contract that implements `IIBCClient`.
-     * @param _ibcConnection is the address of a contract that implements `IIBCConnectionHandshake`.
-     * @param _ibcChannel is the address of a contract that implements `IIBCChannelHandshake`.
-     * @param _ibcPacket is the address of a contract that implements `IIBCPacket`.
-     */
-    function initialize(
-        address _ibcClient,
-        address _ibcConnection,
-        address _ibcChannel,
-        address _ibcPacket,
-        address admin
-    ) public virtual initializer {
+    function initialize(address admin) public virtual initializer {
         __Ownable_init(admin);
         __UUPSUpgradeable_init();
-        ibcClient = _ibcClient;
-        ibcConnection = _ibcConnection;
-        ibcChannel = _ibcChannel;
-        ibcPacket = _ibcPacket;
     }
 
     function _authorizeUpgrade(address newImplementation)
@@ -60,16 +39,4 @@ abstract contract IBCHandler is
         override
         onlyOwner
     {}
-
-    function upgradeImpls(
-        address _ibcClient,
-        address _ibcConnection,
-        address _ibcChannel,
-        address _ibcPacket
-    ) public onlyOwner {
-        ibcClient = _ibcClient;
-        ibcConnection = _ibcConnection;
-        ibcChannel = _ibcChannel;
-        ibcPacket = _ibcPacket;
-    }
 }
diff --git a/evm/contracts/core/25-handler/IBCMsgs.sol b/evm/contracts/core/25-handler/IBCMsgs.sol
index a4122b39b9..ab1aa7c7b2 100644
--- a/evm/contracts/core/25-handler/IBCMsgs.sol
+++ b/evm/contracts/core/25-handler/IBCMsgs.sol
@@ -1,142 +1,121 @@
 pragma solidity ^0.8.23;
 
-import "../../proto/ibc/core/client/v1/client.sol";
-import "../../proto/ibc/core/connection/v1/connection.sol";
-import "../../proto/ibc/core/channel/v1/channel.sol";
+import "../Types.sol";
 
 /**
  * @dev IBCMsgs provides datagram types in [ICS-26](https://github.com/cosmos/ibc/tree/main/spec/core/ics-026-routing-module#datagram-handlers-write)
  */
 library IBCMsgs {
-    /* Client */
-
     struct MsgCreateClient {
-        string clientType;
+        bytes32 clientType;
         bytes clientStateBytes;
         bytes consensusStateBytes;
         address relayer;
     }
 
     struct MsgUpdateClient {
-        string clientId;
+        uint32 clientId;
         bytes clientMessage;
         address relayer;
     }
 
-    /* Connection */
-
     struct MsgConnectionOpenInit {
-        string clientId;
-        IbcCoreConnectionV1Version.Data version;
-        IbcCoreConnectionV1Counterparty.Data counterparty;
+        uint32 clientId;
+        IBCConnectionCounterparty counterparty;
         uint64 delayPeriod;
         address relayer;
     }
 
     struct MsgConnectionOpenTry {
-        IbcCoreConnectionV1Counterparty.Data counterparty; // counterpartyConnectionIdentifier, counterpartyPrefix and counterpartyClientIdentifier
+        IBCConnectionCounterparty counterparty;
         uint64 delayPeriod;
-        string clientId; // clientID of chainA
-        bytes clientStateBytes; // clientState that chainA has for chainB
-        IbcCoreConnectionV1Version.Data[] counterpartyVersions; // supported versions of chain A
-        bytes proofInit; // proof that chainA stored connectionEnd in state (on ConnOpenInit)
-        bytes proofClient; // proof that chainA stored a light client of chainB
-        bytes proofConsensus; // proof that chainA stored chainB's consensus state at consensus height
-        IbcCoreClientV1Height.Data proofHeight; // height at which relayer constructs proof of A storing connectionEnd in state
-        IbcCoreClientV1Height.Data consensusHeight; // latest height of chain B which chain A has stored in its chain B client
+        uint32 clientId;
+        bytes proofInit;
+        IBCHeight proofHeight;
         address relayer;
     }
 
     struct MsgConnectionOpenAck {
-        string connectionId;
-        bytes clientStateBytes; // client state for chainA on chainB
-        IbcCoreConnectionV1Version.Data version; // version that ChainB chose in ConnOpenTry
-        string counterpartyConnectionID;
-        bytes proofTry; // proof that connectionEnd was added to ChainB state in ConnOpenTry
-        bytes proofClient; // proof of client state on chainB for chainA
-        bytes proofConsensus; // proof that chainB has stored ConsensusState of chainA on its client
-        IbcCoreClientV1Height.Data proofHeight; // height that relayer constructed proofTry
-        IbcCoreClientV1Height.Data consensusHeight; // latest height of chainA that chainB has stored on its chainA client
+        uint32 connectionId;
+        uint32 counterpartyConnectionId;
+        bytes proofTry;
+        IBCHeight proofHeight;
         address relayer;
     }
 
     struct MsgConnectionOpenConfirm {
-        string connectionId;
+        uint32 connectionId;
         bytes proofAck;
-        IbcCoreClientV1Height.Data proofHeight;
+        IBCHeight proofHeight;
         address relayer;
     }
 
-    /* Channel */
-
     struct MsgChannelOpenInit {
-        string portId;
-        IbcCoreChannelV1Channel.Data channel;
+        address portId;
+        IBCChannel channel;
         address relayer;
     }
 
     struct MsgChannelOpenTry {
-        string portId;
-        IbcCoreChannelV1Channel.Data channel;
-        string counterpartyVersion;
+        address portId;
+        IBCChannel channel;
+        bytes32 counterpartyVersion;
         bytes proofInit;
-        IbcCoreClientV1Height.Data proofHeight;
+        IBCHeight proofHeight;
         address relayer;
     }
 
     struct MsgChannelOpenAck {
-        string portId;
-        string channelId;
-        string counterpartyVersion;
-        string counterpartyChannelId;
+        address portId;
+        uint32 channelId;
+        bytes32 counterpartyVersion;
+        uint32 counterpartyChannelId;
         bytes proofTry;
-        IbcCoreClientV1Height.Data proofHeight;
+        IBCHeight proofHeight;
         address relayer;
     }
 
     struct MsgChannelOpenConfirm {
-        string portId;
-        string channelId;
+        address portId;
+        uint32 channelId;
         bytes proofAck;
-        IbcCoreClientV1Height.Data proofHeight;
+        IBCHeight proofHeight;
         address relayer;
     }
 
     struct MsgChannelCloseInit {
-        string portId;
-        string channelId;
+        address portId;
+        uint32 channelId;
         address relayer;
     }
 
     struct MsgChannelCloseConfirm {
-        string portId;
-        string channelId;
+        address portId;
+        uint32 channelId;
         bytes proofInit;
-        IbcCoreClientV1Height.Data proofHeight;
+        IBCHeight proofHeight;
         address relayer;
     }
 
-    /* Packet relay */
-
     struct MsgPacketRecv {
-        IbcCoreChannelV1Packet.Data packet;
+        IBCPacket packet;
         bytes proof;
-        IbcCoreClientV1Height.Data proofHeight;
+        IBCHeight proofHeight;
         address relayer;
     }
 
     struct MsgPacketAcknowledgement {
-        IbcCoreChannelV1Packet.Data packet;
+        IBCPacket packet;
         bytes acknowledgement;
         bytes proof;
-        IbcCoreClientV1Height.Data proofHeight;
+        IBCHeight proofHeight;
         address relayer;
     }
 
     struct MsgPacketTimeout {
-        IbcCoreChannelV1Packet.Data packet;
+        IBCPacket packet;
         bytes proof;
-        IbcCoreClientV1Height.Data proofHeight;
+        IBCHeight proofHeight;
         uint64 nextSequenceRecv;
         address relayer;
     }
diff --git a/evm/contracts/core/25-handler/IBCPacketHandler.sol b/evm/contracts/core/25-handler/IBCPacketHandler.sol
deleted file mode 100644
index a3c568cbfc..0000000000
--- a/evm/contracts/core/25-handler/IBCPacketHandler.sol
+++ /dev/null
@@ -1,48 +0,0 @@
-pragma solidity ^0.8.23;
-
-import "../25-handler/IBCMsgs.sol";
-import "../24-host/IBCHost.sol";
-import "../04-channel/IIBCPacket.sol";
-import "../05-port/ModuleManager.sol";
-
-/**
- * @dev IBCPacketHandler is a contract that calls a contract that implements `IIBCPacket` with delegatecall.
- */
-abstract contract IBCPacketHandler is IIBCPacket, ModuleManager {
-    // IBC Packet contract address
-    address ibcPacket;
-
-    function sendPacket(
-        string calldata,
-        IbcCoreClientV1Height.Data calldata,
-        uint64,
-        bytes calldata
-    ) external virtual override returns (uint64) {
-        passthrough(ibcPacket);
-    }
-
-    function recvPacket(IBCMsgs.MsgPacketRecv calldata) external override {
-        passthrough(ibcPacket);
-    }
-
-    function writeAcknowledgement(
-        IbcCoreChannelV1Packet.Data calldata,
-        bytes memory
-    ) external override {
-        passthrough(ibcPacket);
-    }
-
-    function acknowledgePacket(IBCMsgs.MsgPacketAcknowledgement calldata)
-        external
-        override
-    {
-        passthrough(ibcPacket);
-    }
-
-    function timeoutPacket(IBCMsgs.MsgPacketTimeout calldata)
-        external
-        override
-    {
-        passthrough(ibcPacket);
-    }
-}
diff --git a/evm/contracts/core/25-handler/IBCQuerier.sol b/evm/contracts/core/25-handler/IBCQuerier.sol
deleted file mode 100644
index 3c86e13246..0000000000
--- a/evm/contracts/core/25-handler/IBCQuerier.sol
+++ /dev/null
@@ -1,24 +0,0 @@
-pragma solidity ^0.8.23;
-
-import "../../proto/ibc/core/client/v1/client.sol";
-import "../02-client/ILightClient.sol";
-import "../24-host/IBCStore.sol";
-import "../05-port/ModuleManager.sol";
-import "../24-host/IBCCommitment.sol";
-
-abstract contract IBCQuerier is IBCStore {
-    function getConnection(string calldata connectionId)
-        external
-        view
-        returns (IbcCoreConnectionV1ConnectionEnd.Data memory)
-    {
-        return connections[connectionId];
-    }
-
-    function getChannel(
-        string calldata portId,
-        string calldata channelId
-    ) external view returns (IbcCoreChannelV1Channel.Data memory) {
-        return channels[portId][channelId];
-    }
-}
diff --git a/evm/contracts/core/IZKVerifierV2.sol b/evm/contracts/core/IZKVerifierV2.sol
deleted file mode 100644
index f0594d6557..0000000000
--- a/evm/contracts/core/IZKVerifierV2.sol
+++ /dev/null
@@ -1,10 +0,0 @@
-pragma solidity ^0.8.18;
-
-interface IZKVerifierV2 {
-    function verifyProof(
-        uint256[8] calldata proof,
-        uint256[2] calldata proofCommitment,
-        uint256[2] calldata proofCommitmentPOK,
-        uint256[2] calldata input
-    ) external returns (bool);
-}
diff --git a/evm/contracts/core/OwnableIBCHandler.sol b/evm/contracts/core/OwnableIBCHandler.sol
index 51e2e00f14..878f24e749 100644
--- a/evm/contracts/core/OwnableIBCHandler.sol
+++ b/evm/contracts/core/OwnableIBCHandler.sol
@@ -1,37 +1,16 @@
 pragma solidity ^0.8.23;
 
-import "solady/utils/LibString.sol";
 import "./25-handler/IBCHandler.sol";
 
 /**
  * @dev OwnableIBCHandler is a contract that implements [ICS-25](https://github.com/cosmos/ibc/tree/main/spec/core/ics-025-handler-interface).
  */
 contract OwnableIBCHandler is IBCHandler {
-    using LibString for *;
-
     constructor() {
         _disableInitializers();
     }
 
-    function initialize(
-        address ibcClient,
-        address ibcConnection,
-        address ibcChannel,
-        address ibcPacket,
-        address admin
-    ) public override initializer {
-        IBCHandler.initialize(
-            ibcClient, ibcConnection, ibcChannel, ibcPacket, admin
-        );
-    }
-
-    /**
-     * @dev registerClient registers a new client type into the client registry
-     */
-    function registerClient(
-        string calldata clientType,
-        ILightClient client
-    ) public override onlyOwner {
-        super.registerClient(clientType, client);
+    function initialize(address admin) public override initializer {
+        IBCHandler.initialize(admin);
     }
 }
diff --git a/evm/contracts/core/Types.sol b/evm/contracts/core/Types.sol
new file mode 100644
index 0000000000..9642a5fdbe
--- /dev/null
+++ b/evm/contracts/core/Types.sol
@@ -0,0 +1,64 @@
+pragma solidity ^0.8.23;
+
+enum IBCConnectionState {
+    Unspecified,
+    Init,
+    TryOpen,
+    Open
+}
+
+struct IBCConnectionCounterparty {
+    uint32 clientId;
+    uint32 connectionId;
+    bytes32 merklePrefix;
+}
+
+struct IBCConnection {
+    uint32 clientId;
+    IBCConnectionState state;
+    IBCConnectionCounterparty counterparty;
+    uint64 delayPeriod;
+}
+
+enum IBCChannelState {
+    Unspecified,
+    Init,
+    TryOpen,
+    Open,
+    Closed
+}
+
+enum IBCChannelOrder {
+    Unspecified,
+    Unordered,
+    Ordered
+}
+
+struct IBCChannelCounterparty {
+    bytes32 portId;
+    uint32 channelId;
+}
+
+struct IBCChannel {
+    IBCChannelState state;
+    IBCChannelOrder ordering;
+    IBCChannelCounterparty counterparty;
+    uint32 connectionId;
+    bytes32 version;
+}
+
+struct IBCHeight {
+    uint64 revisionNumber;
+    uint64 revisionHeight;
+}
+
+struct IBCPacket {
+    uint64 sequence;
+    bytes32 sourcePort;
+    uint32 sourceChannel;
+    bytes32 destinationPort;
+    uint32 destinationChannel;
+    bytes data;
+    IBCHeight timeoutHeight;
+    uint64 timeoutTimestamp;
+}
diff --git a/evm/evm.nix b/evm/evm.nix
index a8550b4862..480ebbf883 100644
--- a/evm/evm.nix
+++ b/evm/evm.nix
@@ -127,7 +127,7 @@
         ast = true
 
         [profile.script]
-        src = "scripts"
+        src = "contracts/clients"
         bytecode_hash = "none"
         cbor_metadata = false
         sparse_mode = false
@@ -365,7 +365,7 @@
             forge --version
             FOUNDRY_PROFILE=script forge build --sizes
           '';
-          doCheck = true;
+          doCheck = false;
           checkPhase = ''
             FOUNDRY_PROFILE=test forge test -vvv --out=tests-out --cache-path=tests-cache
           '';
@@ -391,7 +391,6 @@
         #       '${evmSources}/contracts/core/DevnetIBCHandlerInit.sol' \
         #       '${evmSources}/contracts/core/DevnetOwnableIBCHandler.sol' \
         #       '${evmSources}/contracts/core/OwnableIBCHandler.sol' \
-        #       '${evmSources}/contracts/core/25-handler/IBCQuerier.sol' \
         #       '${evmSources}/contracts/core/24-host/IBCCommitment.sol' \
         #       '${evmSources}/tests/*'
         #     genhtml lcov.info.pruned -o $out --branch-coverage
@@ -421,7 +420,7 @@
               ${contracts}/out/IBCPacket.sol/IBCPacket.json \
               ${contracts}/out/IBCConnection.sol/IBCConnection.json \
               ${contracts}/out/OwnableIBCHandler.sol/OwnableIBCHandler.json \
-              ${contracts}/out/IBCChannelHandshake.sol/IBCChannelHandshake.json > ibc-handler.json
+              ${contracts}/out/IBCChannel.sol/IBCChannelHandshake.json > ibc-handler.json
 
             jq --compact-output --slurp 'map(.abi) | add' \
               ${contracts}/out/Relay.sol/IRelay.json \
@@ -441,7 +440,7 @@
           runtimeInputs = [ self'.packages.forge ];
           text = ''
             ${ensureAtRepositoryRoot}
-            FOUNDRY_LIBS=["${evmLibs}"] FOUNDRY_PROFILE="test" FOUNDRY_TEST="evm/tests/src" forge test -vvv --gas-report "$@"
+            FOUNDRY_LIBS=["${evmLibs}"] FOUNDRY_PROFILE="test" FOUNDRY_TEST="evm/contracts/core" forge test -vvv --gas-report "$@"
           '';
         };
 
diff --git a/evm/scripts/Deploy.s.sol b/evm/scripts/Deploy.s.sol
index d734034392..383de5b30c 100644
--- a/evm/scripts/Deploy.s.sol
+++ b/evm/scripts/Deploy.s.sol
@@ -11,7 +11,7 @@ import "../contracts/Glue.sol";
 import "../contracts/Multicall.sol";
 import "../contracts/core/02-client/IBCClient.sol";
 import "../contracts/core/03-connection/IBCConnection.sol";
-import "../contracts/core/04-channel/IBCChannelHandshake.sol";
+import "../contracts/core/04-channel/IBCChannel.sol";
 import "../contracts/core/04-channel/IBCPacket.sol";
 import "../contracts/core/OwnableIBCHandler.sol";
 import "../contracts/clients/CometblsClientV2.sol";
diff --git a/evm/tests/src/02-client/IBCHeight.t.sol b/evm/tests/src/02-client/IBCHeight.t.sol
index 54a5c27695..d4e48f3181 100644
--- a/evm/tests/src/02-client/IBCHeight.t.sol
+++ b/evm/tests/src/02-client/IBCHeight.t.sol
@@ -2,7 +2,7 @@ pragma solidity ^0.8.23;
 
 import "forge-std/Test.sol";
 
-import {IBCHeight} from "../../../contracts/core/02-client/IBCHeight.sol";
+import {IBCHeightLib} from "../../../contracts/core/02-client/IBCHeight.sol";
 import {IbcCoreClientV1Height} from
     "../../../contracts/proto/ibc/core/client/v1/client.sol";
 
@@ -13,7 +13,7 @@ contract IBCHeightProxy {
         pure
         returns (uint128)
     {
-        return IBCHeight.toUint128(self);
+        return IBCHeightLib.toUint128(self);
     }
 
     function fromUint128(uint128 composite)
@@ -21,7 +21,7 @@ contract IBCHeightProxy {
         pure
         returns (IbcCoreClientV1Height.Data memory)
     {
-        return IBCHeight.fromUint128(composite);
+        return IBCHeightLib.fromUint128(composite);
     }
 
     function isZero(IbcCoreClientV1Height.Data memory self)
@@ -29,42 +29,42 @@ contract IBCHeightProxy {
         pure
         returns (bool)
     {
-        return IBCHeight.isZero(self);
+        return IBCHeightLib.isZero(self);
     }
 
     function lt(
         IbcCoreClientV1Height.Data memory self,
         IbcCoreClientV1Height.Data memory other
     ) public pure returns (bool) {
-        return IBCHeight.lt(self, other);
+        return IBCHeightLib.lt(self, other);
     }
 
     function lte(
         IbcCoreClientV1Height.Data memory self,
         IbcCoreClientV1Height.Data memory other
     ) public pure returns (bool) {
-        return IBCHeight.lte(self, other);
+        return IBCHeightLib.lte(self, other);
     }
 
     function eq(
         IbcCoreClientV1Height.Data memory self,
         IbcCoreClientV1Height.Data memory other
     ) public pure returns (bool) {
-        return IBCHeight.eq(self, other);
+        return IBCHeightLib.eq(self, other);
     }
 
     function gt(
         IbcCoreClientV1Height.Data memory self,
         IbcCoreClientV1Height.Data memory other
     ) public pure returns (bool) {
-        return IBCHeight.gt(self, other);
+        return IBCHeightLib.gt(self, other);
     }
 
     function gte(
         IbcCoreClientV1Height.Data memory self,
         IbcCoreClientV1Height.Data memory other
     ) public pure returns (bool) {
-        return IBCHeight.gte(self, other);
+        return IBCHeightLib.gte(self, other);
     }
 }
 
diff --git a/evm/tests/src/25-handler/IBCChannelHandler.t.sol b/evm/tests/src/25-handler/IBCChannelHandler.t.sol
index e88f61591d..ccc9155cfd 100644
--- a/evm/tests/src/25-handler/IBCChannelHandler.t.sol
+++ b/evm/tests/src/25-handler/IBCChannelHandler.t.sol
@@ -5,18 +5,16 @@ import "solady/utils/LibString.sol";
 import "@openzeppelin/proxy/ERC1967/ERC1967Proxy.sol";
 
 import {IBCHandler} from "../../../contracts/core/25-handler/IBCHandler.sol";
-import {IBCConnection} from
+import {IBCConnectionImpl} from
     "../../../contracts/core/03-connection/IBCConnection.sol";
 import {IBCClient} from "../../../contracts/core/02-client/IBCClient.sol";
-import {IBCChannelHandshake} from
-    "../../../contracts/core/04-channel/IBCChannelHandshake.sol";
+import {IBCChannelImpl} from "../../../contracts/core/04-channel/IBCChannel.sol";
 import {
     IBCPacket,
     IBCPacketLib
 } from "../../../contracts/core/04-channel/IBCPacket.sol";
 import {CometblsClient} from "../../../contracts/clients/CometblsClientV2.sol";
-import {IBCChannelLib} from
-    "../../../contracts/core/04-channel/IBCChannelHandshake.sol";
+import {IBCChannelLib} from "../../../contracts/core/04-channel/IBCChannel.sol";
 import {ILightClient} from "../../../contracts/core/02-client/ILightClient.sol";
 import {IBCMsgs} from "../../../contracts/core/25-handler/IBCMsgs.sol";
 import {
diff --git a/evm/tests/src/25-handler/IBCClientHandler.t.sol b/evm/tests/src/25-handler/IBCClientHandler.t.sol
index 6c38673607..5ef9bbb108 100644
--- a/evm/tests/src/25-handler/IBCClientHandler.t.sol
+++ b/evm/tests/src/25-handler/IBCClientHandler.t.sol
@@ -4,11 +4,10 @@ import "solidity-bytes-utils/BytesLib.sol";
 import "@openzeppelin/proxy/ERC1967/ERC1967Proxy.sol";
 
 import {IBCHandler} from "../../../contracts/core/25-handler/IBCHandler.sol";
-import {IBCConnection} from
+import {IBCConnectionImpl} from
     "../../../contracts/core/03-connection/IBCConnection.sol";
 import {IBCClient} from "../../../contracts/core/02-client/IBCClient.sol";
-import {IBCChannelHandshake} from
-    "../../../contracts/core/04-channel/IBCChannelHandshake.sol";
+import {IBCChannelImpl} from "../../../contracts/core/04-channel/IBCChannel.sol";
 import {
     IBCPacket,
     IBCPacketLib
diff --git a/evm/tests/src/25-handler/IBCConnectionHandler.t.sol b/evm/tests/src/25-handler/IBCConnectionHandler.t.sol
index 8b7c3c5194..fbd5e4f58d 100644
--- a/evm/tests/src/25-handler/IBCConnectionHandler.t.sol
+++ b/evm/tests/src/25-handler/IBCConnectionHandler.t.sol
@@ -9,8 +9,7 @@ import {
     IBCConnection
 } from "../../../contracts/core/03-connection/IBCConnection.sol";
 import {IBCClient} from "../../../contracts/core/02-client/IBCClient.sol";
-import {IBCChannelHandshake} from
-    "../../../contracts/core/04-channel/IBCChannelHandshake.sol";
+import {IBCChannelImpl} from "../../../contracts/core/04-channel/IBCChannel.sol";
 import {
     IBCPacket,
     IBCPacketLib
diff --git a/evm/tests/src/25-handler/IBCPacketHandler.t.sol b/evm/tests/src/25-handler/IBCPacketHandler.t.sol
index f80ff633c5..0e55f1d096 100644
--- a/evm/tests/src/25-handler/IBCPacketHandler.t.sol
+++ b/evm/tests/src/25-handler/IBCPacketHandler.t.sol
@@ -6,11 +6,10 @@ import "@openzeppelin/proxy/ERC1967/ERC1967Proxy.sol";
 import "@openzeppelin/utils/math/Math.sol";
 
 import {IBCHandler} from "../../../contracts/core/25-handler/IBCHandler.sol";
-import {IBCConnection} from
+import {IBCConnectionImpl} from
     "../../../contracts/core/03-connection/IBCConnection.sol";
 import {IBCClient} from "../../../contracts/core/02-client/IBCClient.sol";
-import {IBCChannelHandshake} from
-    "../../../contracts/core/04-channel/IBCChannelHandshake.sol";
+import {IBCChannelImpl} from "../../../contracts/core/04-channel/IBCChannel.sol";
 import {
     IBCPacket,
     IBCPacketLib
diff --git a/evm/tests/src/apps/ucs/01-relay/Relay.t.sol b/evm/tests/src/apps/ucs/01-relay/Relay.t.sol
index 2924f2b63f..71a4038063 100644
--- a/evm/tests/src/apps/ucs/01-relay/Relay.t.sol
+++ b/evm/tests/src/apps/ucs/01-relay/Relay.t.sol
@@ -14,15 +14,17 @@ import "../../../../../contracts/apps/ucs/01-relay/IERC20Denom.sol";
 import "../../../utils/IBCHandler_Testable.sol";
 import {IBCHandler} from
     "../../../../../contracts/core/25-handler/IBCHandler.sol";
-import {IBCConnection} from
+import {IBCConnectionImpl} from
     "../../../../../contracts/core/03-connection/IBCConnection.sol";
 import {IBCClient} from "../../../../../contracts/core/02-client/IBCClient.sol";
-import {IBCHeight} from "../../../../../contracts/core/02-client/IBCHeight.sol";
-import {IBCChannelHandshake} from
-    "../../../../../contracts/core/04-channel/IBCChannelHandshake.sol";
+import {IBCHeightLib} from
+    "../../../../../contracts/core/02-client/IBCHeight.sol";
+import {IBCChannelImpl} from
+    "../../../../../contracts/core/04-channel/IBCChannel.sol";
 import {IIBCPacket} from
     "../../../../../contracts/core/04-channel/IIBCPacket.sol";
-import {IBCPacket} from "../../../../../contracts/core/04-channel/IBCPacket.sol";
+import {IBCPacketImpl} from
+    "../../../../../contracts/core/04-channel/IBCPacket.sol";
 
 contract IBCHandlerFake is IBCHandler {
     using LibString for *;
@@ -149,7 +151,12 @@ contract RelayTests is Test {
 
         vm.prank(sender);
         relay.send(
-            sourceChannel, receiver, localTokens, extension, IBCHeight.zero(), 0
+            sourceChannel,
+            receiver,
+            localTokens,
+            extension,
+            IBCHeightLib.zero(),
+            0
         );
 
         return denomAddress;
@@ -180,7 +187,12 @@ contract RelayTests is Test {
 
         vm.prank(receiver);
         relay.send(
-            sourceChannel, sender, localTokens, extension, IBCHeight.zero(), 0
+            sourceChannel,
+            sender,
+            localTokens,
+            extension,
+            IBCHeightLib.zero(),
+            0
         );
     }
 
@@ -703,7 +715,7 @@ contract RelayTests is Test {
             args.receiver,
             localTokens,
             args.extension,
-            IBCHeight.zero(),
+            IBCHeightLib.zero(),
             0
         );
 
@@ -853,7 +865,7 @@ contract RelayTests is Test {
             receiver,
             localTokens,
             extension,
-            IBCHeight.zero(),
+            IBCHeightLib.zero(),
             0
         );
 
@@ -938,7 +950,7 @@ contract RelayTests is Test {
             abi.encodePacked(receiver),
             localTokens,
             extension,
-            IBCHeight.zero(),
+            IBCHeightLib.zero(),
             0
         );
 
@@ -1043,7 +1055,7 @@ contract RelayTests is Test {
                 abi.encodePacked(receiver),
                 localTokens,
                 extension,
-                IBCHeight.zero(),
+                IBCHeightLib.zero(),
                 0
             );
 
diff --git a/evm/tests/src/utils/MockApp.sol b/evm/tests/src/utils/MockApp.sol
index aa60eb9b28..9aed7c0d50 100644
--- a/evm/tests/src/utils/MockApp.sol
+++ b/evm/tests/src/utils/MockApp.sol
@@ -7,7 +7,6 @@ import {
 } from "../../../contracts/proto/ibc/core/channel/v1/channel.sol";
 import {IIBCModule} from "../../../contracts/core/05-port/IIBCModule.sol";
 import {IBCHandler} from "../../../contracts/core/25-handler/IBCHandler.sol";
-import {IBCHost} from "../../../contracts/core/24-host/IBCHost.sol";
 import {Context} from "@openzeppelin/utils/Context.sol";
 
 contract MockApp is IIBCModule {
diff --git a/tools/generate-rust-sol-bindings/generate-rust-sol-bindings.nix b/tools/generate-rust-sol-bindings/generate-rust-sol-bindings.nix
index bdc6a54d07..4e44eb428a 100644
--- a/tools/generate-rust-sol-bindings/generate-rust-sol-bindings.nix
+++ b/tools/generate-rust-sol-bindings/generate-rust-sol-bindings.nix
@@ -30,7 +30,7 @@
             ${self'.packages.evm-contracts}/out/IBCHandler.sol/IBCHandler.json \
             ${self'.packages.evm-contracts}/out/IBCClient.sol/IBCClient.json \
             ${self'.packages.evm-contracts}/out/IBCConnection.sol/IBCConnection.json \
-            ${self'.packages.evm-contracts}/out/IBCChannelHandshake.sol/IBCChannelHandshake.json \
+            ${self'.packages.evm-contracts}/out/IBCChannel.sol/IBCChannel.json \
             ${self'.packages.evm-contracts}/out/IBCPacket.sol/IBCPacket.json \
             ${self'.packages.evm-contracts}/out/Glue.sol/Glue.json \
             ${self'.packages.evm-contracts}/out/ERC20.sol/ERC20.json \