diff --git a/Cargo.Bazel.lock b/Cargo.Bazel.lock
index 1f15a2331..6d7158858 100644
--- a/Cargo.Bazel.lock
+++ b/Cargo.Bazel.lock
@@ -1,5 +1,5 @@
 {
-  "checksum": "8f276b46cbd4dab6df35c316a7bc7ed6716d52e987e3b60aa1a127416a00915a",
+  "checksum": "ac1c7f35e7cd235485ebc4e9085ef127ba2881abba9deee4940ac3a40ac97b9a",
   "crates": {
     "actix-codec 0.5.2": {
       "name": "actix-codec",
@@ -5739,13 +5739,13 @@
       },
       "license": "MIT OR Apache-2.0"
     },
-    "clap_complete 4.5.24": {
+    "clap_complete 4.5.26": {
       "name": "clap_complete",
-      "version": "4.5.24",
+      "version": "4.5.26",
       "repository": {
         "Http": {
-          "url": "https://static.crates.io/crates/clap_complete/4.5.24/download",
-          "sha256": "6d7db6eca8c205649e8d3ccd05aa5042b1800a784e56bc7c43524fde8abbfa9b"
+          "url": "https://static.crates.io/crates/clap_complete/4.5.26/download",
+          "sha256": "205d5ef6d485fa47606b98b0ddc4ead26eb850aaa86abfb562a94fb3280ecba0"
         }
       },
       "targets": [
@@ -5780,7 +5780,7 @@
           "selects": {}
         },
         "edition": "2021",
-        "version": "4.5.24"
+        "version": "4.5.26"
       },
       "license": "MIT OR Apache-2.0"
     },
@@ -8838,6 +8838,10 @@
               "id": "ic-base-types 0.9.0",
               "target": "ic_base_types"
             },
+            {
+              "id": "indexmap 2.5.0",
+              "target": "indexmap"
+            },
             {
               "id": "itertools 0.13.0",
               "target": "itertools"
@@ -10082,7 +10086,7 @@
               "target": "clap_num"
             },
             {
-              "id": "clap_complete 4.5.24",
+              "id": "clap_complete 4.5.26",
               "target": "clap_complete"
             },
             {
@@ -10213,6 +10217,10 @@
               "id": "ic-types 0.9.0",
               "target": "ic_types"
             },
+            {
+              "id": "indexmap 2.5.0",
+              "target": "indexmap"
+            },
             {
               "id": "itertools 0.13.0",
               "target": "itertools"
@@ -19828,6 +19836,10 @@
               "id": "ic-types 0.9.0",
               "target": "ic_types"
             },
+            {
+              "id": "indexmap 2.5.0",
+              "target": "indexmap"
+            },
             {
               "id": "itertools 0.13.0",
               "target": "itertools"
@@ -20071,6 +20083,10 @@
               "id": "ic-types 0.9.0",
               "target": "ic_types"
             },
+            {
+              "id": "indexmap 2.5.0",
+              "target": "indexmap"
+            },
             {
               "id": "registry-canister 0.9.0",
               "target": "registry_canister"
@@ -29689,6 +29705,10 @@
               "id": "ic-types 0.9.0",
               "target": "ic_types"
             },
+            {
+              "id": "indexmap 2.5.0",
+              "target": "indexmap"
+            },
             {
               "id": "rand 0.8.5",
               "target": "rand"
diff --git a/Cargo.lock b/Cargo.lock
index 65f17edae..dc573fea0 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1139,9 +1139,9 @@ dependencies = [
 
 [[package]]
 name = "clap_complete"
-version = "4.5.24"
+version = "4.5.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6d7db6eca8c205649e8d3ccd05aa5042b1800a784e56bc7c43524fde8abbfa9b"
+checksum = "205d5ef6d485fa47606b98b0ddc4ead26eb850aaa86abfb562a94fb3280ecba0"
 dependencies = [
  "clap 4.5.16",
 ]
@@ -1749,6 +1749,7 @@ dependencies = [
  "futures",
  "ic-base-types",
  "ic-management-types",
+ "indexmap 2.5.0",
  "itertools 0.13.0",
  "log",
  "rand",
@@ -2029,6 +2030,7 @@ dependencies = [
  "ic-sns-wasm",
  "ic-sys",
  "ic-types",
+ "indexmap 2.5.0",
  "itertools 0.13.0",
  "keyring",
  "log",
@@ -3987,6 +3989,7 @@ dependencies = [
  "ic-registry-nns-data-provider",
  "ic-registry-subnet-type",
  "ic-types",
+ "indexmap 2.5.0",
  "itertools 0.13.0",
  "lazy_static",
  "log",
@@ -4039,6 +4042,7 @@ dependencies = [
  "ic-protobuf",
  "ic-registry-subnet-type",
  "ic-types",
+ "indexmap 2.5.0",
  "registry-canister",
  "reqwest",
  "serde",
@@ -5989,6 +5993,7 @@ dependencies = [
  "ic-management-backend",
  "ic-management-types",
  "ic-types",
+ "indexmap 2.5.0",
  "pretty_assertions",
  "rand",
  "reqwest",
diff --git a/Cargo.toml b/Cargo.toml
index f962ee2bc..021bc34b4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -64,7 +64,7 @@ clap = { version = "4.5", features = [
     "string",
     "cargo",
 ] }
-clap_complete = "4.5.24"
+clap_complete = "4.5.26"
 clio = { version = "0.3.5", features = ["clap", "clap-parse"] }
 colored = "2.1.0"
 comfy-table = "7.1.1"
diff --git a/rs/cli/Cargo.toml b/rs/cli/Cargo.toml
index bef90da28..8bad18b74 100644
--- a/rs/cli/Cargo.toml
+++ b/rs/cli/Cargo.toml
@@ -49,6 +49,7 @@ ic-registry-subnet-type = { workspace = true }
 ic-sns-wasm = { workspace = true }
 ic-sys = { workspace = true }
 ic-types = { workspace = true }
+indexmap = { workspace = true }
 itertools = { workspace = true }
 log = { workspace = true }
 pretty_env_logger = { workspace = true }
diff --git a/rs/cli/src/commands/hostos/rollout_from_node_group.rs b/rs/cli/src/commands/hostos/rollout_from_node_group.rs
index 3d33e358e..6c9e410f6 100644
--- a/rs/cli/src/commands/hostos/rollout_from_node_group.rs
+++ b/rs/cli/src/commands/hostos/rollout_from_node_group.rs
@@ -7,7 +7,7 @@ use crate::{
     operations::hostos_rollout::{NodeGroupUpdate, NumberOfNodes},
 };
 
-#[derive(ValueEnum, Copy, Clone, Debug, Ord, Eq, PartialEq, PartialOrd, Default)]
+#[derive(ValueEnum, Copy, Clone, Debug, Ord, Eq, PartialEq, PartialOrd, Default, Hash)]
 pub enum NodeOwner {
     Dfinity,
     Others,
@@ -25,7 +25,7 @@ impl std::fmt::Display for NodeOwner {
     }
 }
 
-#[derive(ValueEnum, Copy, Clone, Debug, Ord, Eq, PartialEq, PartialOrd, Default)]
+#[derive(ValueEnum, Copy, Clone, Debug, Ord, Eq, PartialEq, PartialOrd, Default, Hash)]
 pub enum NodeAssignment {
     Unassigned,
     Assigned,
diff --git a/rs/cli/src/commands/registry.rs b/rs/cli/src/commands/registry.rs
index 04c337b8f..1eb97a588 100644
--- a/rs/cli/src/commands/registry.rs
+++ b/rs/cli/src/commands/registry.rs
@@ -16,6 +16,7 @@ use ic_protobuf::registry::{
 };
 use ic_registry_subnet_type::SubnetType;
 use ic_types::PrincipalId;
+use indexmap::IndexMap;
 use itertools::Itertools;
 use log::{info, warn};
 use serde::Serialize;
@@ -83,7 +84,7 @@ impl Registry {
 
         // Calculate number of rewardable nodes for node operators
         for node_operator in node_operators.values_mut() {
-            let mut nodes_by_health = BTreeMap::new();
+            let mut nodes_by_health = IndexMap::new();
             for node_details in nodes.iter().filter(|n| n.node_operator_id == node_operator.node_operator_principal_id) {
                 let node_id = node_details.node_id;
                 let health = node_details.status.to_string();
@@ -129,7 +130,7 @@ fn get_elected_host_os_versions(local_registry: &Arc<dyn LazyRegistry>) -> anyho
     local_registry.elected_hostos_records()
 }
 
-async fn get_node_operators(local_registry: &Arc<dyn LazyRegistry>, network: &Network) -> anyhow::Result<BTreeMap<PrincipalId, NodeOperator>> {
+async fn get_node_operators(local_registry: &Arc<dyn LazyRegistry>, network: &Network) -> anyhow::Result<IndexMap<PrincipalId, NodeOperator>> {
     let all_nodes = local_registry.nodes().await?;
     let operators = local_registry
         .operators()
@@ -163,7 +164,7 @@ async fn get_node_operators(local_registry: &Arc<dyn LazyRegistry>, network: &Ne
                 },
             )
         })
-        .collect::<BTreeMap<_, _>>();
+        .collect::<IndexMap<_, _>>();
     Ok(node_operators)
 }
 
@@ -203,7 +204,7 @@ fn get_unassigned_nodes(local_registry: &Arc<dyn LazyRegistry>) -> anyhow::Resul
 
 async fn get_nodes(
     local_registry: &Arc<dyn LazyRegistry>,
-    node_operators: &BTreeMap<PrincipalId, NodeOperator>,
+    node_operators: &IndexMap<PrincipalId, NodeOperator>,
     subnets: &[SubnetRecord],
     network: &Network,
 ) -> anyhow::Result<Vec<NodeDetails>> {
@@ -260,7 +261,7 @@ fn get_node_rewards_table(local_registry: &Arc<dyn LazyRegistry>, network: &Netw
                 panic!("Failed to get Node Rewards Table for mainnet")
             } else {
                 warn!("Failed to get Node Rewards Table for {}", network.name);
-                BTreeMap::new()
+                IndexMap::new()
             }
         }
     };
@@ -361,7 +362,7 @@ struct NodeDetails {
 struct SubnetRecord {
     subnet_id: PrincipalId,
     membership: Vec<String>,
-    nodes: BTreeMap<PrincipalId, NodeDetails>,
+    nodes: IndexMap<PrincipalId, NodeDetails>,
     max_ingress_bytes_per_message: u64,
     max_ingress_messages_per_block: u64,
     max_block_payload_size: u64,
@@ -393,7 +394,7 @@ struct NodeOperator {
     rewardable_nodes: BTreeMap<String, u32>,
     ipv6: Option<String>,
     total_up_nodes: u32,
-    nodes_health: BTreeMap<String, Vec<PrincipalId>>,
+    nodes_health: IndexMap<String, Vec<PrincipalId>>,
     rewards_correct: bool,
 }
 
diff --git a/rs/cli/src/commands/update_authorized_subnets.rs b/rs/cli/src/commands/update_authorized_subnets.rs
index af1b1fb40..18ca9c2b3 100644
--- a/rs/cli/src/commands/update_authorized_subnets.rs
+++ b/rs/cli/src/commands/update_authorized_subnets.rs
@@ -1,4 +1,5 @@
-use std::{collections::BTreeMap, path::PathBuf, sync::Arc};
+use indexmap::IndexMap;
+use std::{path::PathBuf, sync::Arc};
 
 use clap::{error::ErrorKind, Args};
 use ic_management_types::Subnet;
@@ -54,7 +55,7 @@ impl ExecutableCommand for UpdateAuthorizedSubnets {
 
         let registry = ctx.registry().await;
         let subnets = registry.subnets().await?;
-        let mut excluded_subnets = BTreeMap::new();
+        let mut excluded_subnets = IndexMap::new();
 
         let human_bytes = human_bytes::human_bytes(self.state_size_limit as f64);
         let agent = ctx.create_ic_agent_canister_client(None)?;
@@ -87,11 +88,11 @@ impl ExecutableCommand for UpdateAuthorizedSubnets {
             }
         }
 
-        let summary = construct_summary(&subnets, &excluded_subnets)?;
+        let summary = construct_summary(&subnets, &excluded_subnets, ctx.forum_post_link())?;
 
         let authorized = subnets
             .keys()
-            .filter(|subnet_id| !excluded_subnets.contains_key(subnet_id))
+            .filter(|subnet_id| !excluded_subnets.contains_key(*subnet_id))
             .cloned()
             .collect();
 
@@ -136,13 +137,19 @@ impl UpdateAuthorizedSubnets {
     }
 }
 
-fn construct_summary(subnets: &Arc<BTreeMap<PrincipalId, Subnet>>, excluded_subnets: &BTreeMap<PrincipalId, String>) -> anyhow::Result<String> {
+fn construct_summary(
+    subnets: &Arc<IndexMap<PrincipalId, Subnet>>,
+    excluded_subnets: &IndexMap<PrincipalId, String>,
+    forum_post_link: Option<String>,
+) -> anyhow::Result<String> {
     Ok(format!(
         "Updating the list of authorized subnets to:
 
 | Subnet id | Public | Description |
 | --------- | ------ | ----------- |
-{}",
+{}
+{}
+",
         subnets
             .values()
             .map(|s| {
@@ -154,6 +161,10 @@ fn construct_summary(subnets: &Arc<BTreeMap<PrincipalId, Subnet>>, excluded_subn
                     excluded_desc.map(|s| s.to_string()).unwrap_or_default()
                 )
             })
-            .join("\n")
+            .join("\n"),
+        match forum_post_link {
+            Some(link) => format!("\nForum post link: {}", link),
+            None => "".to_string(),
+        }
     ))
 }
diff --git a/rs/cli/src/operations/hostos_rollout.rs b/rs/cli/src/operations/hostos_rollout.rs
index 16b86c08e..88001f4a4 100644
--- a/rs/cli/src/operations/hostos_rollout.rs
+++ b/rs/cli/src/operations/hostos_rollout.rs
@@ -5,9 +5,10 @@ use ic_base_types::{NodeId, PrincipalId};
 use ic_management_backend::health::{self, HealthStatusQuerier};
 use ic_management_backend::proposal::ProposalAgent;
 use ic_management_types::{HealthStatus, Network, Node, Subnet, UpdateNodesHostosVersionsProposal};
+use indexmap::IndexMap;
 use log::{debug, info, warn};
 use std::sync::Arc;
-use std::{collections::BTreeMap, fmt::Display, str::FromStr};
+use std::{fmt::Display, str::FromStr};
 
 use crate::commands::hostos::rollout_from_node_group::{NodeAssignment, NodeOwner};
 
@@ -39,7 +40,7 @@ impl Display for HostosRolloutReason {
     }
 }
 
-#[derive(Copy, Clone, Debug, Ord, Eq, PartialEq, PartialOrd)]
+#[derive(Copy, Clone, Debug, Ord, Eq, PartialEq, PartialOrd, Hash)]
 pub struct NodeGroup {
     pub assignment: NodeAssignment,
     pub owner: NodeOwner,
@@ -129,8 +130,8 @@ enum CandidatesSelection {
 #[derive(Clone)]
 pub struct HostosRollout {
     nodes_all: Vec<Node>,
-    pub grouped_nodes: BTreeMap<NodeGroup, Vec<Node>>,
-    pub subnets: Arc<BTreeMap<PrincipalId, Subnet>>,
+    pub grouped_nodes: IndexMap<NodeGroup, Vec<Node>>,
+    pub subnets: Arc<IndexMap<PrincipalId, Subnet>>,
     pub network: Network,
     pub proposal_agent: Arc<dyn ProposalAgent>,
     pub only_filter: Vec<String>,
@@ -139,15 +140,15 @@ pub struct HostosRollout {
 }
 impl HostosRollout {
     pub fn new(
-        nodes: Arc<BTreeMap<PrincipalId, Node>>,
-        subnets: Arc<BTreeMap<PrincipalId, Subnet>>,
+        nodes: Arc<IndexMap<PrincipalId, Node>>,
+        subnets: Arc<IndexMap<PrincipalId, Subnet>>,
         network: &Network,
         proposal_agent: Arc<dyn ProposalAgent>,
         rollout_version: &str,
         only_filter: &[String],
         exclude_filter: &[String],
     ) -> Self {
-        let grouped_nodes: BTreeMap<NodeGroup, Vec<Node>> = nodes
+        let grouped_nodes: IndexMap<NodeGroup, Vec<Node>> = nodes
             .values()
             .cloned()
             .map(|node| {
@@ -169,7 +170,7 @@ impl HostosRollout {
                 );
                 (NodeGroup::new(assignment, owner), node)
             })
-            .fold(BTreeMap::new(), |mut acc, (node_group, node)| {
+            .fold(IndexMap::new(), |mut acc, (node_group, node)| {
                 acc.entry(node_group).or_default().push(node);
                 acc
             });
@@ -219,12 +220,12 @@ impl HostosRollout {
             .collect()
     }
 
-    async fn nodes_by_status(&self, nodes: Vec<Node>, nodes_health: BTreeMap<PrincipalId, HealthStatus>) -> BTreeMap<HealthStatus, Vec<Node>> {
+    async fn nodes_by_status(&self, nodes: Vec<Node>, nodes_health: IndexMap<PrincipalId, HealthStatus>) -> IndexMap<HealthStatus, Vec<Node>> {
         let nodes_by_status = nodes
             .iter()
             .cloned()
             .map(|node| (nodes_health.get(&node.principal).cloned().unwrap_or(HealthStatus::Unknown), node))
-            .fold(BTreeMap::new(), |mut acc: BTreeMap<HealthStatus, Vec<Node>>, (status, node)| {
+            .fold(IndexMap::new(), |mut acc: IndexMap<HealthStatus, Vec<Node>>, (status, node)| {
                 acc.entry(status).or_default().push(node);
                 acc
             });
@@ -325,7 +326,7 @@ impl HostosRollout {
 
     async fn candidates_selection(
         &self,
-        nodes_health: BTreeMap<PrincipalId, HealthStatus>,
+        nodes_health: IndexMap<PrincipalId, HealthStatus>,
         nodes_with_open_proposals: Vec<UpdateNodesHostosVersionsProposal>,
         nodes_in_group: Vec<Node>,
     ) -> anyhow::Result<CandidatesSelection> {
@@ -363,7 +364,7 @@ impl HostosRollout {
     #[async_recursion]
     async fn with_nodes_health_and_open_proposals(
         &self,
-        nodes_health: BTreeMap<PrincipalId, HealthStatus>,
+        nodes_health: IndexMap<PrincipalId, HealthStatus>,
         nodes_with_open_proposals: Vec<UpdateNodesHostosVersionsProposal>,
         update_group: NodeGroupUpdate,
     ) -> anyhow::Result<HostosRolloutResponse> {
@@ -535,6 +536,7 @@ pub mod test {
     use crate::operations::hostos_rollout::NodeOwner::{Dfinity, Others};
     use ic_management_backend::proposal::ProposalAgentImpl;
     use ic_management_types::{Network, Node, Operator, Provider, Subnet};
+    use std::collections::BTreeMap;
     use std::net::Ipv6Addr;
 
     use super::*;
@@ -548,7 +550,7 @@ pub mod test {
         let assigned_dfinity = gen_test_nodes(Some(subnet_id), 10, 0, version_one.clone(), true, false);
         let unassigned_dfinity_nodes = gen_test_nodes(None, 10, 10, version_one.clone(), true, false);
         let assigned_others_nodes = gen_test_nodes(Some(subnet_id), 10, 20, version_two.clone(), false, false);
-        let union: BTreeMap<PrincipalId, Node> = {
+        let union: IndexMap<PrincipalId, Node> = {
             assigned_dfinity
                 .clone()
                 .into_iter()
@@ -559,7 +561,7 @@ pub mod test {
         let union_nodes = union.values().cloned().collect::<Vec<_>>();
 
         let subnet = {
-            let mut sub = BTreeMap::new();
+            let mut sub = IndexMap::new();
             sub.insert(
                 subnet_id,
                 Subnet {
@@ -575,7 +577,7 @@ pub mod test {
             .keys()
             .cloned()
             .map(|principal| (principal, HealthStatus::Healthy))
-            .collect::<BTreeMap<PrincipalId, HealthStatus>>();
+            .collect::<IndexMap<PrincipalId, HealthStatus>>();
 
         let open_proposals: Vec<UpdateNodesHostosVersionsProposal> = vec![];
 
@@ -685,8 +687,8 @@ pub mod test {
         hostos_version: String,
         dfinity_owned: bool,
         is_api_boundary_node: bool,
-    ) -> BTreeMap<PrincipalId, Node> {
-        let mut n = BTreeMap::new();
+    ) -> IndexMap<PrincipalId, Node> {
+        let mut n = IndexMap::new();
         for i in start_at_number..start_at_number + num_nodes {
             let node = Node {
                 principal: PrincipalId::new_node_test_id(i),
diff --git a/rs/cli/src/runner.rs b/rs/cli/src/runner.rs
index 8a4d4d235..9f487fcab 100644
--- a/rs/cli/src/runner.rs
+++ b/rs/cli/src/runner.rs
@@ -1,6 +1,4 @@
 use std::cell::RefCell;
-use std::collections::BTreeMap;
-use std::collections::BTreeSet;
 use std::sync::Arc;
 
 use decentralization::network::DecentralizedSubnet;
@@ -28,6 +26,7 @@ use ic_management_types::NodeFeature;
 use ic_management_types::Release;
 use ic_management_types::TopologyChangePayload;
 use ic_types::PrincipalId;
+use indexmap::{IndexMap, IndexSet};
 use itertools::Itertools;
 use log::info;
 use log::warn;
@@ -120,7 +119,7 @@ impl Runner {
         Ok(())
     }
 
-    pub async fn health_of_nodes(&self) -> anyhow::Result<BTreeMap<PrincipalId, HealthStatus>> {
+    pub async fn health_of_nodes(&self) -> anyhow::Result<IndexMap<PrincipalId, HealthStatus>> {
         let health_client = health::HealthClient::new(self.network.clone());
         health_client.nodes().await
     }
@@ -130,7 +129,7 @@ impl Runner {
         request: ic_management_types::requests::SubnetResizeRequest,
         motivation: String,
         forum_post_link: Option<String>,
-        health_of_nodes: &BTreeMap<PrincipalId, HealthStatus>,
+        health_of_nodes: &IndexMap<PrincipalId, HealthStatus>,
     ) -> anyhow::Result<()> {
         let change = self
             .registry
@@ -571,7 +570,7 @@ impl Runner {
                 None => true,
             })
             .map(|(id, subnet)| (*id, subnet.clone()))
-            .collect::<BTreeMap<_, _>>();
+            .collect::<IndexMap<_, _>>();
         let (available_nodes, health_of_nodes) =
             try_join(self.registry.available_nodes().map_err(anyhow::Error::from), health_client.nodes()).await?;
 
@@ -677,8 +676,8 @@ impl Runner {
         let ic_repo = self.ic_repo().await;
         let hosts = ic_repo.hostos_releases().await?;
         let active_releases = hosts.get_active_branches();
-        let hostos_versions: BTreeSet<String> = self.registry.nodes().await?.values().map(|s| s.hostos_version.clone()).collect();
-        let versions_in_proposals: BTreeSet<String> = self
+        let hostos_versions: IndexSet<String> = self.registry.nodes().await?.values().map(|s| s.hostos_version.clone()).collect();
+        let versions_in_proposals: IndexSet<String> = self
             .proposal_agent
             .list_open_elect_hostos_proposals()
             .await?
@@ -704,9 +703,9 @@ impl Runner {
         let ic_repo = self.ic_repo().await;
         let guests = ic_repo.guestos_releases().await?;
         let active_releases = guests.get_active_branches();
-        let subnet_versions: BTreeSet<String> = self.registry.subnets().await?.values().map(|s| s.replica_version.clone()).collect();
+        let subnet_versions: IndexSet<String> = self.registry.subnets().await?.values().map(|s| s.replica_version.clone()).collect();
         let version_on_unassigned_nodes = self.registry.unassigned_nodes_replica_version().await?;
-        let versions_in_proposals: BTreeSet<String> = self
+        let versions_in_proposals: IndexSet<String> = self
             .proposal_agent
             .list_open_elect_replica_proposals()
             .await?
@@ -816,7 +815,7 @@ pub fn replace_proposal_options(change: &SubnetChangeResponse, forum_post_link:
     })
 }
 
-fn nodes_by_dc(nodes: Vec<Node>) -> BTreeMap<String, Vec<(String, String)>> {
+fn nodes_by_dc(nodes: Vec<Node>) -> IndexMap<String, Vec<(String, String)>> {
     nodes
         .iter()
         .cloned()
@@ -832,7 +831,7 @@ fn nodes_by_dc(nodes: Vec<Node>) -> BTreeMap<String, Vec<(String, String)>> {
                 n.operator.datacenter,
             )
         })
-        .fold(BTreeMap::new(), |mut acc, (node_id, subnet, dc)| {
+        .fold(IndexMap::new(), |mut acc, (node_id, subnet, dc)| {
             acc.entry(dc.unwrap_or_default().name).or_default().push((node_id, subnet));
             acc
         })
diff --git a/rs/cli/src/unit_tests/version.rs b/rs/cli/src/unit_tests/version.rs
index 02f98defe..07f767961 100644
--- a/rs/cli/src/unit_tests/version.rs
+++ b/rs/cli/src/unit_tests/version.rs
@@ -1,7 +1,5 @@
-use std::{
-    collections::BTreeMap,
-    sync::{Arc, RwLock},
-};
+use indexmap::IndexMap;
+use std::sync::{Arc, RwLock};
 
 use futures::future::ok;
 use ic_management_backend::{lazy_git::MockLazyGit, lazy_registry::MockLazyRegistry, proposal::MockProposalAgent};
@@ -35,7 +33,7 @@ async fn guest_os_elect_version_tests() {
         .returning(|| Box::pin(ok(Arc::new(ArtifactReleases::new(ic_management_types::Artifact::GuestOs)))));
 
     let mut registry = MockLazyRegistry::new();
-    registry.expect_subnets().returning(|| Box::pin(ok(Arc::new(BTreeMap::new()))));
+    registry.expect_subnets().returning(|| Box::pin(ok(Arc::new(IndexMap::new()))));
     registry
         .expect_unassigned_nodes_replica_version()
         .returning(|| Box::pin(ok(Arc::new("some_ver".to_string()))));
diff --git a/rs/decentralization/Cargo.toml b/rs/decentralization/Cargo.toml
index 19732d935..05d7815fb 100644
--- a/rs/decentralization/Cargo.toml
+++ b/rs/decentralization/Cargo.toml
@@ -14,6 +14,7 @@ ahash = { workspace = true }
 anyhow = { workspace = true }
 ic-base-types = { workspace = true }
 ic-management-types = { workspace = true }
+indexmap = { workspace = true }
 itertools = { workspace = true }
 log = { workspace = true }
 rand = { workspace = true }
diff --git a/rs/decentralization/src/lib.rs b/rs/decentralization/src/lib.rs
index c74f47ecc..e351ceeb2 100644
--- a/rs/decentralization/src/lib.rs
+++ b/rs/decentralization/src/lib.rs
@@ -1,8 +1,8 @@
 pub mod nakamoto;
 pub mod network;
 pub mod subnets;
+use indexmap::IndexMap;
 use itertools::Itertools;
-use std::collections::BTreeMap;
 use std::fmt::{Display, Formatter};
 
 use ic_base_types::PrincipalId;
@@ -15,17 +15,17 @@ pub struct SubnetChangeResponse {
     pub removed_with_desc: Vec<(PrincipalId, String)>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub subnet_id: Option<PrincipalId>,
-    pub health_of_nodes: BTreeMap<PrincipalId, HealthStatus>,
+    pub health_of_nodes: IndexMap<PrincipalId, HealthStatus>,
     pub score_before: nakamoto::NakamotoScore,
     pub score_after: nakamoto::NakamotoScore,
     pub motivation: Option<String>,
     pub comment: Option<String>,
     pub run_log: Option<Vec<String>>,
-    pub feature_diff: BTreeMap<NodeFeature, FeatureDiff>,
+    pub feature_diff: IndexMap<NodeFeature, FeatureDiff>,
     pub proposal_id: Option<u64>,
 }
 
-pub type FeatureDiff = BTreeMap<String, (usize, usize)>;
+pub type FeatureDiff = IndexMap<String, (usize, usize)>;
 
 impl SubnetChangeResponse {
     pub fn with_motivation(self, motivation: String) -> Self {
@@ -34,7 +34,7 @@ impl SubnetChangeResponse {
             ..self
         }
     }
-    pub fn with_health_of_nodes(self, health_of_nodes: BTreeMap<PrincipalId, HealthStatus>) -> Self {
+    pub fn with_health_of_nodes(self, health_of_nodes: IndexMap<PrincipalId, HealthStatus>) -> Self {
         SubnetChangeResponse { health_of_nodes, ..self }
     }
 }
@@ -45,7 +45,7 @@ impl From<&network::SubnetChange> for SubnetChangeResponse {
             added_with_desc: change.added().iter().map(|n| (n.0.id, n.1.clone())).collect(),
             removed_with_desc: change.removed().iter().map(|n| (n.0.id, n.1.clone())).collect(),
             subnet_id: if change.id == Default::default() { None } else { Some(change.id) },
-            health_of_nodes: BTreeMap::new(),
+            health_of_nodes: IndexMap::new(),
             score_before: nakamoto::NakamotoScore::new_from_nodes(&change.old_nodes),
             score_after: nakamoto::NakamotoScore::new_from_nodes(&change.new_nodes),
             motivation: None,
@@ -56,7 +56,7 @@ impl From<&network::SubnetChange> for SubnetChangeResponse {
                     NodeFeature::variants()
                         .into_iter()
                         .map(|f| (f, FeatureDiff::new()))
-                        .collect::<BTreeMap<NodeFeature, FeatureDiff>>(),
+                        .collect::<IndexMap<NodeFeature, FeatureDiff>>(),
                     |mut acc, n| {
                         for f in NodeFeature::variants() {
                             acc.get_mut(&f).unwrap().entry(n.get_feature(&f)).or_insert((0, 0)).0 += 1;
diff --git a/rs/decentralization/src/nakamoto/mod.rs b/rs/decentralization/src/nakamoto/mod.rs
index 2b9fb455a..3a520d1b7 100644
--- a/rs/decentralization/src/nakamoto/mod.rs
+++ b/rs/decentralization/src/nakamoto/mod.rs
@@ -1,10 +1,11 @@
 use crate::network::Node;
 use ahash::{AHashMap, AHasher};
+use indexmap::IndexMap;
 use itertools::Itertools;
 use serde::{Deserialize, Serialize};
 use std::cell::RefCell;
 use std::cmp::Ordering;
-use std::collections::{BTreeMap, VecDeque};
+use std::collections::VecDeque;
 use std::fmt::{self, Debug, Display, Formatter};
 use std::hash::Hasher;
 use std::iter::{FromIterator, IntoIterator};
@@ -13,7 +14,7 @@ use ic_management_types::NodeFeature;
 
 #[derive(Eq, PartialEq, Clone, Serialize, Deserialize, Debug)]
 pub struct NodeFeatures {
-    pub feature_map: BTreeMap<NodeFeature, String>,
+    pub feature_map: IndexMap<NodeFeature, String>,
 }
 
 impl fmt::Display for NodeFeatures {
@@ -32,7 +33,7 @@ impl NodeFeatures {
 
     #[cfg(test)]
     fn new_test_feature_set(value: &str) -> Self {
-        let mut result = BTreeMap::new();
+        let mut result = IndexMap::new();
         for feature in NodeFeature::variants() {
             result.insert(feature, value.to_string());
         }
@@ -50,7 +51,7 @@ impl NodeFeatures {
 impl FromIterator<(NodeFeature, &'static str)> for NodeFeatures {
     fn from_iter<I: IntoIterator<Item = (NodeFeature, &'static str)>>(iter: I) -> Self {
         Self {
-            feature_map: BTreeMap::from_iter(iter.into_iter().map(|x| (x.0, String::from(x.1)))),
+            feature_map: IndexMap::from_iter(iter.into_iter().map(|x| (x.0, String::from(x.1)))),
         }
     }
 }
@@ -58,7 +59,7 @@ impl FromIterator<(NodeFeature, &'static str)> for NodeFeatures {
 impl FromIterator<(NodeFeature, std::string::String)> for NodeFeatures {
     fn from_iter<I: IntoIterator<Item = (NodeFeature, std::string::String)>>(iter: I) -> Self {
         Self {
-            feature_map: BTreeMap::from_iter(iter),
+            feature_map: IndexMap::from_iter(iter),
         }
     }
 }
@@ -77,9 +78,9 @@ thread_local! {
 /// For instance: [NodeFeature::NodeProvider], [NodeFeature::DataCenter], etc...
 /// For a complete reference check [NodeFeature]
 pub struct NakamotoScore {
-    coefficients: BTreeMap<NodeFeature, f64>,
-    value_counts: BTreeMap<NodeFeature, Vec<(String, usize)>>,
-    controlled_nodes: BTreeMap<NodeFeature, usize>,
+    coefficients: IndexMap<NodeFeature, f64>,
+    value_counts: IndexMap<NodeFeature, Vec<(String, usize)>>,
+    controlled_nodes: IndexMap<NodeFeature, usize>,
     avg_linear: f64,
 
     /// This field needs to be optional in case we get a -inf result because of
@@ -101,13 +102,13 @@ pub struct NakamotoScore {
 impl NakamotoScore {
     /// Build a new NakamotoScore object from a slice of [NodeFeatures].
     pub fn new_from_slice_node_features(slice_node_features: &[NodeFeatures]) -> Self {
-        let mut features_to_nodes_map = BTreeMap::new();
+        let mut features_to_nodes_map = IndexMap::new();
 
         for feature in NodeFeature::variants() {
             features_to_nodes_map.insert(feature, Vec::new());
         }
 
-        // Convert a Vec<BTreeMap<NodeFeature, Value>> into a Vec<BTreeMap<NodeFeature,
+        // Convert a Vec<IndexMap<NodeFeature, Value>> into a Vec<IndexMap<NodeFeature,
         // Vec<Values>>
         for node_features in slice_node_features.iter() {
             for feature in NodeFeature::variants() {
@@ -158,9 +159,9 @@ impl NakamotoScore {
         let scores = nakamoto_calc
             .clone()
             .map(|(f, n, _)| (f, n.0 as f64))
-            .collect::<BTreeMap<NodeFeature, f64>>();
+            .collect::<IndexMap<NodeFeature, f64>>();
 
-        let controlled_nodes = nakamoto_calc.clone().map(|(f, n, _)| (f, n.1)).collect::<BTreeMap<NodeFeature, usize>>();
+        let controlled_nodes = nakamoto_calc.clone().map(|(f, n, _)| (f, n.1)).collect::<IndexMap<NodeFeature, usize>>();
 
         let value_counts = nakamoto_calc.map(|(f, _, value_counts)| (f, value_counts)).collect();
 
@@ -290,7 +291,7 @@ impl NakamotoScore {
     }
 
     /// Get a Map with all the features and the corresponding Nakamoto score
-    pub fn scores_individual(&self) -> BTreeMap<NodeFeature, f64> {
+    pub fn scores_individual(&self) -> IndexMap<NodeFeature, f64> {
         self.coefficients.clone()
     }
 
@@ -568,6 +569,7 @@ mod tests {
     use ahash::HashSet;
     use ic_base_types::PrincipalId;
     use ic_management_types::HealthStatus;
+    use indexmap::IndexMap;
     use itertools::Itertools;
     use regex::Regex;
 
@@ -604,7 +606,7 @@ mod tests {
         let score = NakamotoScore::new_from_slice_node_features(&features);
 
         let score_expected = NakamotoScore {
-            coefficients: BTreeMap::from([
+            coefficients: IndexMap::from([
                 (NodeFeature::City, 1.),
                 (NodeFeature::Country, 1.),
                 (NodeFeature::Continent, 1.),
@@ -612,8 +614,8 @@ mod tests {
                 (NodeFeature::NodeProvider, 1.),
                 (NodeFeature::DataCenter, 1.),
             ]),
-            value_counts: BTreeMap::new(),
-            controlled_nodes: BTreeMap::from([
+            value_counts: IndexMap::new(),
+            controlled_nodes: IndexMap::from([
                 (NodeFeature::City, 1),
                 (NodeFeature::Country, 1),
                 (NodeFeature::Continent, 1),
@@ -771,7 +773,7 @@ mod tests {
             .iter()
             .chain(subnet_initial.nodes.iter())
             .map(|n| (n.id, HealthStatus::Healthy))
-            .collect::<BTreeMap<_, _>>();
+            .collect::<IndexMap<_, _>>();
 
         println!(
             "initial {} Countries {:?}",
@@ -828,7 +830,7 @@ mod tests {
             )
         );
         let nodes_available = new_test_nodes_with_overrides("spare", 7, 2, 0, (&NodeFeature::NodeProvider, &["NP6", "NP7"]));
-        let health_of_nodes = nodes_available.iter().map(|n| (n.id, HealthStatus::Healthy)).collect::<BTreeMap<_, _>>();
+        let health_of_nodes = nodes_available.iter().map(|n| (n.id, HealthStatus::Healthy)).collect::<IndexMap<_, _>>();
 
         println!(
             "initial {} NPs {:?}",
@@ -886,7 +888,7 @@ mod tests {
             .iter()
             .chain(subnet_initial.nodes.iter())
             .map(|n| (n.id, HealthStatus::Healthy))
-            .collect::<BTreeMap<_, _>>();
+            .collect::<IndexMap<_, _>>();
 
         println!(
             "initial {} NPs {:?}",
@@ -1099,8 +1101,8 @@ mod tests {
                     (n, HealthStatus::Healthy)
                 }
             })
-            .collect::<BTreeMap<_, _>>();
-        let mut important = BTreeMap::new();
+            .collect::<IndexMap<_, _>>();
+        let mut important = IndexMap::new();
 
         important.insert(subnet.principal, subnet);
 
@@ -1124,7 +1126,7 @@ mod tests {
             .iter()
             .chain(subnet_initial.nodes.iter())
             .map(|n| (n.id, HealthStatus::Healthy))
-            .collect::<BTreeMap<_, _>>();
+            .collect::<IndexMap<_, _>>();
 
         let change_initial = SubnetChangeRequest::new(subnet_initial.clone(), nodes_available, Vec::new(), Vec::new(), Vec::new(), None);
 
diff --git a/rs/decentralization/src/network.rs b/rs/decentralization/src/network.rs
index 339f57fea..a58f38d26 100644
--- a/rs/decentralization/src/network.rs
+++ b/rs/decentralization/src/network.rs
@@ -8,12 +8,12 @@ use anyhow::anyhow;
 use futures::future::BoxFuture;
 use ic_base_types::PrincipalId;
 use ic_management_types::{HealthStatus, MinNakamotoCoefficients, NetworkError, NodeFeature};
+use indexmap::IndexMap;
 use itertools::Itertools;
 use log::{debug, info, warn};
 use rand::{seq::SliceRandom, SeedableRng};
 use serde::{Deserialize, Serialize};
 use std::cmp::Ordering;
-use std::collections::BTreeMap;
 use std::fmt::{Debug, Display, Formatter};
 use std::hash::Hash;
 
@@ -880,7 +880,7 @@ pub trait TopologyManager: SubnetQuerier + AvailableNodesQuerier + Sync {
         include_nodes: Vec<PrincipalId>,
         exclude_nodes: Vec<String>,
         only_nodes: Vec<String>,
-        health_of_nodes: &'a BTreeMap<PrincipalId, HealthStatus>,
+        health_of_nodes: &'a IndexMap<PrincipalId, HealthStatus>,
     ) -> BoxFuture<'a, Result<SubnetChange, NetworkError>> {
         Box::pin(async move {
             SubnetChangeRequest {
@@ -1029,7 +1029,7 @@ impl SubnetChangeRequest {
         mut self,
         optimize_count: usize,
         replacements_unhealthy_with_desc: &[(Node, String)],
-        health_of_nodes: &BTreeMap<PrincipalId, HealthStatus>,
+        health_of_nodes: &IndexMap<PrincipalId, HealthStatus>,
     ) -> Result<SubnetChange, NetworkError> {
         let old_nodes = self.subnet.nodes.clone();
         self.subnet = self.subnet.without_nodes(replacements_unhealthy_with_desc.to_owned())?;
@@ -1042,7 +1042,7 @@ impl SubnetChangeRequest {
         Ok(SubnetChange { old_nodes, ..result })
     }
 
-    pub fn rescue(mut self, health_of_nodes: &BTreeMap<PrincipalId, HealthStatus>) -> Result<SubnetChange, NetworkError> {
+    pub fn rescue(mut self, health_of_nodes: &IndexMap<PrincipalId, HealthStatus>) -> Result<SubnetChange, NetworkError> {
         let old_nodes = self.subnet.nodes.clone();
         let nodes_to_remove = self
             .subnet
@@ -1074,7 +1074,7 @@ impl SubnetChangeRequest {
         how_many_nodes_to_add: usize,
         how_many_nodes_to_remove: usize,
         how_many_nodes_unhealthy: usize,
-        health_of_nodes: &BTreeMap<PrincipalId, HealthStatus>,
+        health_of_nodes: &IndexMap<PrincipalId, HealthStatus>,
     ) -> Result<SubnetChange, NetworkError> {
         let old_nodes = self.subnet.nodes.clone();
 
@@ -1137,7 +1137,7 @@ impl SubnetChangeRequest {
     /// Evaluates the subnet change request to simulate the requested topology
     /// change. Command returns all the information about the subnet before
     /// and after the change.
-    pub fn evaluate(self, health_of_nodes: &BTreeMap<PrincipalId, HealthStatus>) -> Result<SubnetChange, NetworkError> {
+    pub fn evaluate(self, health_of_nodes: &IndexMap<PrincipalId, HealthStatus>) -> Result<SubnetChange, NetworkError> {
         self.resize(0, 0, 0, health_of_nodes)
     }
 }
@@ -1235,18 +1235,18 @@ impl Ord for NetworkHealSubnets {
 }
 
 pub struct NetworkHealRequest {
-    pub subnets: BTreeMap<PrincipalId, ic_management_types::Subnet>,
+    pub subnets: IndexMap<PrincipalId, ic_management_types::Subnet>,
 }
 
 impl NetworkHealRequest {
-    pub fn new(subnets: BTreeMap<PrincipalId, ic_management_types::Subnet>) -> Self {
+    pub fn new(subnets: IndexMap<PrincipalId, ic_management_types::Subnet>) -> Self {
         Self { subnets }
     }
 
     pub async fn heal_and_optimize(
         &self,
         mut available_nodes: Vec<Node>,
-        health_of_nodes: &BTreeMap<PrincipalId, HealthStatus>,
+        health_of_nodes: &IndexMap<PrincipalId, HealthStatus>,
     ) -> Result<Vec<SubnetChangeResponse>, NetworkError> {
         let mut subnets_changed = Vec::new();
         let subnets_to_heal = unhealthy_with_nodes(&self.subnets, health_of_nodes)
diff --git a/rs/decentralization/src/subnets.rs b/rs/decentralization/src/subnets.rs
index 83d90ed7c..0400b748b 100644
--- a/rs/decentralization/src/subnets.rs
+++ b/rs/decentralization/src/subnets.rs
@@ -1,17 +1,17 @@
-use std::{collections::BTreeMap, sync::Arc};
-
 use crate::network::Node;
 use ic_base_types::PrincipalId;
 use ic_management_types::{
     requests::{NodeRemoval, NodeRemovalReason},
     HealthStatus, Subnet,
 };
+use indexmap::IndexMap;
 use itertools::Itertools;
+use std::sync::Arc;
 
 pub async fn unhealthy_with_nodes(
-    subnets: &BTreeMap<PrincipalId, Subnet>,
-    nodes_health: &BTreeMap<PrincipalId, HealthStatus>,
-) -> BTreeMap<PrincipalId, Vec<ic_management_types::Node>> {
+    subnets: &IndexMap<PrincipalId, Subnet>,
+    nodes_health: &IndexMap<PrincipalId, HealthStatus>,
+) -> IndexMap<PrincipalId, Vec<ic_management_types::Node>> {
     subnets
         .clone()
         .into_iter()
@@ -31,7 +31,7 @@ pub async fn unhealthy_with_nodes(
                 None
             }
         })
-        .collect::<BTreeMap<_, _>>()
+        .collect::<IndexMap<_, _>>()
 }
 
 pub struct NodesRemover {
@@ -45,14 +45,14 @@ pub struct NodesRemover {
 impl NodesRemover {
     pub fn remove_nodes(
         &self,
-        mut healths: std::collections::BTreeMap<ic_base_types::PrincipalId, ic_management_types::HealthStatus>,
-        nodes_with_proposals: Arc<std::collections::BTreeMap<ic_base_types::PrincipalId, ic_management_types::Node>>,
+        mut healths: IndexMap<ic_base_types::PrincipalId, ic_management_types::HealthStatus>,
+        nodes_with_proposals: Arc<IndexMap<ic_base_types::PrincipalId, ic_management_types::Node>>,
     ) -> (Vec<NodeRemoval>, String) {
         let nodes_to_rm = nodes_with_proposals
             .values()
             .cloned()
             .map(|n| {
-                let status = healths.remove(&n.principal).unwrap_or(ic_management_types::HealthStatus::Unknown);
+                let status = healths.shift_remove(&n.principal).unwrap_or(ic_management_types::HealthStatus::Unknown);
                 (n, status)
             })
             .filter(|(n, _)| n.proposal.is_none())
diff --git a/rs/ic-management-backend/Cargo.toml b/rs/ic-management-backend/Cargo.toml
index baa5fcea8..f3ab77a48 100644
--- a/rs/ic-management-backend/Cargo.toml
+++ b/rs/ic-management-backend/Cargo.toml
@@ -41,6 +41,7 @@ ic-registry-local-store = { workspace = true }
 ic-registry-nns-data-provider = { workspace = true }
 ic-registry-subnet-type = { workspace = true }
 ic-types = { workspace = true }
+indexmap = { workspace = true }
 itertools = { workspace = true }
 lazy_static = { workspace = true }
 log = { workspace = true }
diff --git a/rs/ic-management-backend/src/endpoints/mod.rs b/rs/ic-management-backend/src/endpoints/mod.rs
index d614b0b69..18fd8dac0 100644
--- a/rs/ic-management-backend/src/endpoints/mod.rs
+++ b/rs/ic-management-backend/src/endpoints/mod.rs
@@ -12,9 +12,9 @@ use decentralization::network::AvailableNodesQuerier;
 use ic_management_types::Network;
 use ic_registry_nns_data_provider::registry::RegistryCanister;
 use ic_types::PrincipalId;
+use indexmap::IndexMap;
 use log::{debug, info};
 use serde::{Deserialize, Serialize};
-use std::collections::BTreeMap;
 use std::ops::Deref;
 use std::str::FromStr;
 use std::sync::Arc;
@@ -224,10 +224,10 @@ async fn nodes_healths(registry: web::Data<Arc<RwLock<registry::RegistryState>>>
             .map(|n| {
                 (
                     n.principal,
-                    healths.remove(&n.principal).unwrap_or(ic_management_types::HealthStatus::Unknown),
+                    healths.shift_remove(&n.principal).unwrap_or(ic_management_types::HealthStatus::Unknown),
                 )
             })
-            .collect::<BTreeMap<_, _>>()
+            .collect::<IndexMap<_, _>>()
     }))
 }
 
diff --git a/rs/ic-management-backend/src/endpoints/subnet.rs b/rs/ic-management-backend/src/endpoints/subnet.rs
index ab1b4ec93..80f3d0fef 100644
--- a/rs/ic-management-backend/src/endpoints/subnet.rs
+++ b/rs/ic-management-backend/src/endpoints/subnet.rs
@@ -2,8 +2,8 @@ use super::*;
 use crate::subnets::get_proposed_subnet_changes;
 use ic_base_types::PrincipalId;
 use ic_management_types::Node;
+use indexmap::IndexMap;
 use serde::Deserialize;
-use std::collections::BTreeMap;
 
 #[derive(Deserialize)]
 struct SubnetRequest {
@@ -20,7 +20,7 @@ pub(crate) async fn change_preview(
             let subnet = subnets
                 .get(&request.subnet)
                 .ok_or_else(|| actix_web::error::ErrorNotFound(anyhow::format_err!("subnet {} not found", request.subnet)))?;
-            let registry_nodes: BTreeMap<PrincipalId, Node> = registry.read().await.nodes();
+            let registry_nodes: IndexMap<PrincipalId, Node> = registry.read().await.nodes();
 
             get_proposed_subnet_changes(&registry_nodes, subnet)
                 .map_err(actix_web::error::ErrorBadRequest)
diff --git a/rs/ic-management-backend/src/health.rs b/rs/ic-management-backend/src/health.rs
index a2ad9740d..c3532d4d6 100644
--- a/rs/ic-management-backend/src/health.rs
+++ b/rs/ic-management-backend/src/health.rs
@@ -1,7 +1,5 @@
-use std::{
-    collections::{BTreeMap, HashSet},
-    str::FromStr,
-};
+use indexmap::IndexMap;
+use std::{collections::HashSet, str::FromStr};
 
 use ic_base_types::PrincipalId;
 use ic_management_types::{HealthStatus, Network};
@@ -26,14 +24,14 @@ impl HealthClient {
 }
 
 impl HealthStatusQuerier for HealthClient {
-    async fn subnet(&self, subnet: PrincipalId) -> anyhow::Result<BTreeMap<PrincipalId, HealthStatus>> {
+    async fn subnet(&self, subnet: PrincipalId) -> anyhow::Result<IndexMap<PrincipalId, HealthStatus>> {
         match &self.implementation {
             HealthStatusQuerierImplementations::Dashboard(c) => c.subnet(subnet).await,
             HealthStatusQuerierImplementations::Prometheus(c) => c.subnet(subnet).await,
         }
     }
 
-    async fn nodes(&self) -> anyhow::Result<BTreeMap<PrincipalId, HealthStatus>> {
+    async fn nodes(&self) -> anyhow::Result<IndexMap<PrincipalId, HealthStatus>> {
         match &self.implementation {
             HealthStatusQuerierImplementations::Dashboard(c) => c.nodes().await,
             HealthStatusQuerierImplementations::Prometheus(c) => c.nodes().await,
@@ -57,8 +55,8 @@ impl From<Network> for HealthStatusQuerierImplementations {
 }
 
 pub trait HealthStatusQuerier {
-    fn subnet(&self, subnet: PrincipalId) -> impl std::future::Future<Output = anyhow::Result<BTreeMap<PrincipalId, HealthStatus>>> + Send;
-    fn nodes(&self) -> impl std::future::Future<Output = anyhow::Result<BTreeMap<PrincipalId, HealthStatus>>> + Send;
+    fn subnet(&self, subnet: PrincipalId) -> impl std::future::Future<Output = anyhow::Result<IndexMap<PrincipalId, HealthStatus>>> + Send;
+    fn nodes(&self) -> impl std::future::Future<Output = anyhow::Result<IndexMap<PrincipalId, HealthStatus>>> + Send;
 }
 
 pub struct PublicDashboardHealthClient {
@@ -186,7 +184,7 @@ struct ShortNodeInfo {
 }
 
 impl HealthStatusQuerier for PublicDashboardHealthClient {
-    async fn subnet(&self, subnet: PrincipalId) -> anyhow::Result<BTreeMap<PrincipalId, HealthStatus>> {
+    async fn subnet(&self, subnet: PrincipalId) -> anyhow::Result<IndexMap<PrincipalId, HealthStatus>> {
         Ok(self
             .get_all_nodes()
             .await?
@@ -199,7 +197,7 @@ impl HealthStatusQuerier for PublicDashboardHealthClient {
             .collect())
     }
 
-    async fn nodes(&self) -> anyhow::Result<BTreeMap<PrincipalId, HealthStatus>> {
+    async fn nodes(&self) -> anyhow::Result<IndexMap<PrincipalId, HealthStatus>> {
         Ok(self.get_all_nodes().await?.into_iter().map(|n| (n.node_id, n.status)).collect())
     }
 }
@@ -219,7 +217,7 @@ impl PrometheusHealthClient {
 }
 
 impl HealthStatusQuerier for PrometheusHealthClient {
-    async fn subnet(&self, subnet: PrincipalId) -> anyhow::Result<BTreeMap<PrincipalId, HealthStatus>> {
+    async fn subnet(&self, subnet: PrincipalId) -> anyhow::Result<IndexMap<PrincipalId, HealthStatus>> {
         let ic_name = self.network.legacy_name();
         let subnet_name = subnet.to_string();
         let query_up = Selector::new()
@@ -264,7 +262,7 @@ impl HealthStatusQuerier for PrometheusHealthClient {
             .collect())
     }
 
-    async fn nodes(&self) -> anyhow::Result<BTreeMap<PrincipalId, HealthStatus>> {
+    async fn nodes(&self) -> anyhow::Result<IndexMap<PrincipalId, HealthStatus>> {
         let query = format!(
             r#"ic_replica_orchestrator:health_state:bottomk_1{{ic="{network}"}}"#,
             network = self.network.legacy_name(),
diff --git a/rs/ic-management-backend/src/lazy_registry.rs b/rs/ic-management-backend/src/lazy_registry.rs
index c46509820..b53fbe23c 100644
--- a/rs/ic-management-backend/src/lazy_registry.rs
+++ b/rs/ic-management-backend/src/lazy_registry.rs
@@ -1,5 +1,4 @@
-use std::collections::BTreeMap;
-use std::collections::{BTreeSet, HashSet};
+use indexmap::{IndexMap, IndexSet};
 use std::net::Ipv6Addr;
 use std::str::FromStr;
 use std::sync::Arc;
@@ -63,15 +62,15 @@ pub trait LazyRegistry:
 
     fn sync_with_nns(&self) -> BoxFuture<'_, anyhow::Result<()>>;
 
-    fn operators(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Operator>>>>;
+    fn operators(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Operator>>>>;
 
-    fn nodes(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Node>>>>;
+    fn nodes(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Node>>>>;
 
     fn firewall_rule_set(&self, firewall_rule_scope: FirewallRulesScope) -> BoxFuture<'_, anyhow::Result<FirewallRuleSet>>;
 
-    fn subnets(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Subnet>>>>;
+    fn subnets(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Subnet>>>>;
 
-    fn nodes_with_proposals(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Node>>>>;
+    fn nodes_with_proposals(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Node>>>>;
 
     fn nns_replica_version(&self) -> BoxFuture<'_, anyhow::Result<Option<String>>> {
         Box::pin(async {
@@ -118,7 +117,7 @@ pub trait LazyRegistry:
 
     fn get_api_boundary_nodes(&self) -> anyhow::Result<Vec<(String, ApiBoundaryNodeRecord)>>;
 
-    fn get_node_rewards_table(&self) -> anyhow::Result<BTreeMap<String, NodeRewardsTable>>;
+    fn get_node_rewards_table(&self) -> anyhow::Result<IndexMap<String, NodeRewardsTable>>;
 
     fn get_unassigned_nodes(&self) -> anyhow::Result<Option<UnassignedNodesConfigRecord>>;
 
@@ -130,7 +129,7 @@ pub trait LazyRegistry:
 
     fn update_proposal_data(&self) -> BoxFuture<'_, anyhow::Result<()>>;
 
-    fn subnets_and_proposals(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Subnet>>>> {
+    fn subnets_and_proposals(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Subnet>>>> {
         Box::pin(async {
             let subnets = self.subnets().await?;
 
@@ -174,14 +173,14 @@ where
     local_registry: LocalRegistry,
     network: Network,
 
-    subnets: RwLock<Option<Arc<BTreeMap<PrincipalId, Subnet>>>>,
-    nodes: RwLock<Option<Arc<BTreeMap<PrincipalId, Node>>>>,
-    operators: RwLock<Option<Arc<BTreeMap<PrincipalId, Operator>>>>,
+    subnets: RwLock<Option<Arc<IndexMap<PrincipalId, Subnet>>>>,
+    nodes: RwLock<Option<Arc<IndexMap<PrincipalId, Node>>>>,
+    operators: RwLock<Option<Arc<IndexMap<PrincipalId, Operator>>>>,
     node_labels_guests: RwLock<Option<Arc<Vec<Guest>>>>,
     elected_guestos: RwLock<Option<Arc<Vec<String>>>>,
     elected_hostos: RwLock<Option<Arc<Vec<String>>>>,
     unassigned_nodes_replica_version: RwLock<Option<Arc<String>>>,
-    firewall_rule_set: RwLock<Option<Arc<BTreeMap<String, FirewallRuleSet>>>>,
+    firewall_rule_set: RwLock<Option<Arc<IndexMap<String, FirewallRuleSet>>>>,
     no_sync: bool,
     proposal_agent: Arc<dyn ProposalAgent>,
 }
@@ -236,17 +235,17 @@ pub trait LazyRegistryFamilyEntries {
     fn get_latest_version(&self) -> RegistryVersion;
 }
 
-fn get_family_entries<T: LazyRegistryEntry + Default>(reg: &impl LazyRegistryFamilyEntries) -> anyhow::Result<BTreeMap<String, T>> {
+fn get_family_entries<T: LazyRegistryEntry + Default>(reg: &impl LazyRegistryFamilyEntries) -> anyhow::Result<IndexMap<String, T>> {
     let family = get_family_entries_versioned::<T>(reg)?;
     Ok(family.into_iter().map(|(k, (_, v))| (k, v)).collect())
 }
-fn get_family_entries_versioned<T: LazyRegistryEntry + Default>(reg: &impl LazyRegistryFamilyEntries) -> anyhow::Result<BTreeMap<String, (u64, T)>> {
+fn get_family_entries_versioned<T: LazyRegistryEntry + Default>(reg: &impl LazyRegistryFamilyEntries) -> anyhow::Result<IndexMap<String, (u64, T)>> {
     get_family_entries_of_version(reg, reg.get_latest_version())
 }
 fn get_family_entries_of_version<T: LazyRegistryEntry + Default>(
     reg: &impl LazyRegistryFamilyEntries,
     version: RegistryVersion,
-) -> anyhow::Result<BTreeMap<String, (u64, T)>> {
+) -> anyhow::Result<IndexMap<String, (u64, T)>> {
     let prefix_length = T::KEY_PREFIX.len();
     Ok(reg
         .get_key_family(T::KEY_PREFIX, version)?
@@ -406,7 +405,7 @@ impl LazyRegistry for LazyRegistryImpl {
         })
     }
 
-    fn operators(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Operator>>>> {
+    fn operators(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Operator>>>> {
         Box::pin(async {
             if let Some(operators) = self.operators.read().await.as_ref() {
                 return Ok(operators.to_owned());
@@ -417,11 +416,11 @@ impl LazyRegistry for LazyRegistryImpl {
                 false => query_ic_dashboard_list::<NodeProvidersResponse>(&self.network, "v3/node-providers").await?,
                 true => NodeProvidersResponse { node_providers: vec![] },
             };
-            let node_providers: BTreeMap<_, _> = node_providers.node_providers.iter().map(|p| (p.principal_id, p)).collect();
+            let node_providers: IndexMap<_, _> = node_providers.node_providers.iter().map(|p| (p.principal_id, p)).collect();
             let data_centers = get_family_entries::<DataCenterRecord>(self)?;
             let operators = get_family_entries::<NodeOperatorRecord>(self)?;
 
-            let records: BTreeMap<_, _> = operators
+            let records: IndexMap<_, _> = operators
                 .iter()
                 .map(|(p, or)| {
                     let principal = PrincipalId::from_str(p).expect("Invalid operator principal id");
@@ -462,7 +461,7 @@ impl LazyRegistry for LazyRegistryImpl {
                                     longitude: dc.gps.clone().map(|l| l.longitude as f64),
                                 }
                             }),
-                            rewardable_nodes: or.rewardable_nodes.clone(),
+                            rewardable_nodes: or.rewardable_nodes.iter().map(|(k, v)| (k.clone(), *v)).collect(),
                             ipv6: or.ipv6().to_string(),
                         },
                     )
@@ -475,7 +474,7 @@ impl LazyRegistry for LazyRegistryImpl {
         })
     }
 
-    fn nodes(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Node>>>> {
+    fn nodes(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Node>>>> {
         Box::pin(async {
             if let Some(nodes) = self.nodes.read().await.as_ref() {
                 return Ok(nodes.to_owned());
@@ -483,11 +482,11 @@ impl LazyRegistry for LazyRegistryImpl {
 
             let node_entries = get_family_entries::<NodeRecord>(self)?;
             let versioned_node_entries = get_family_entries_versioned::<NodeRecord>(self)?;
-            let dfinity_dcs = DFINITY_DCS.split(' ').map(|dc| dc.to_string().to_lowercase()).collect::<HashSet<_>>();
+            let dfinity_dcs = DFINITY_DCS.split(' ').map(|dc| dc.to_string().to_lowercase()).collect::<IndexSet<_>>();
             let api_boundary_nodes = get_family_entries::<ApiBoundaryNodeRecord>(self)?;
             let guests = self.node_labels().await?;
             let operators = self.operators().await?;
-            let nodes: BTreeMap<_, _> = node_entries
+            let nodes: IndexMap<_, _> = node_entries
                 .iter()
                 .map(|(p, nr)| {
                     let guest = Self::node_record_guest(guests.clone(), nr);
@@ -587,7 +586,7 @@ impl LazyRegistry for LazyRegistryImpl {
                 let bag = Arc::make_mut(arc_map);
                 bag.insert(key.to_owned(), value.clone());
             } else {
-                let mut all = BTreeMap::new();
+                let mut all = IndexMap::new();
                 all.insert(key.to_owned(), value.clone());
                 *opt_arc_map = Some(Arc::new(all));
             }
@@ -596,7 +595,7 @@ impl LazyRegistry for LazyRegistryImpl {
         })
     }
 
-    fn subnets(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Subnet>>>> {
+    fn subnets(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Subnet>>>> {
         Box::pin(async {
             if let Some(subnets) = self.subnets.read().await.as_ref() {
                 return Ok(subnets.to_owned());
@@ -604,7 +603,7 @@ impl LazyRegistry for LazyRegistryImpl {
 
             let all_nodes = self.nodes().await?;
 
-            let subnets: BTreeMap<_, _> = get_family_entries::<SubnetRecord>(self)?
+            let subnets: IndexMap<_, _> = get_family_entries::<SubnetRecord>(self)?
                 .iter()
                 .enumerate()
                 .map(|(i, (p, sr))| {
@@ -672,7 +671,7 @@ impl LazyRegistry for LazyRegistryImpl {
         })
     }
 
-    fn nodes_with_proposals(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Node>>>> {
+    fn nodes_with_proposals(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Node>>>> {
         Box::pin(async {
             let nodes = self.nodes().await?;
             if nodes.iter().any(|(_, n)| n.proposal.is_some()) {
@@ -694,7 +693,7 @@ impl LazyRegistry for LazyRegistryImpl {
             let subnets = self.subnets().await?;
 
             let topology_proposals = self.proposal_agent.list_open_topology_proposals().await?;
-            let nodes: BTreeMap<_, _> = nodes
+            let nodes: IndexMap<_, _> = nodes
                 .iter()
                 .map(|(p, n)| {
                     let proposal = topology_proposals
@@ -706,7 +705,7 @@ impl LazyRegistry for LazyRegistryImpl {
                 })
                 .collect();
 
-            let subnets: BTreeMap<_, _> = subnets
+            let subnets: IndexMap<_, _> = subnets
                 .iter()
                 .map(|(p, s)| {
                     let proposal = topology_proposals
@@ -785,7 +784,7 @@ impl LazyRegistry for LazyRegistryImpl {
             .collect_vec())
     }
 
-    fn get_node_rewards_table(&self) -> anyhow::Result<BTreeMap<String, NodeRewardsTable>> {
+    fn get_node_rewards_table(&self) -> anyhow::Result<IndexMap<String, NodeRewardsTable>> {
         get_family_entries::<NodeRewardsTable>(self).map_err(|e| anyhow::anyhow!("Couldn't get node rewards table: {:?}", e))
     }
 
@@ -852,7 +851,7 @@ impl SubnetQuerier for LazyRegistryImpl {
                     let subnets = nodes
                         .iter()
                         .map(|n| reg_nodes.get(&n.id).and_then(|n| n.subnet_id))
-                        .collect::<BTreeSet<_>>();
+                        .collect::<IndexSet<_>>();
                     if subnets.len() > 1 {
                         return Err(NetworkError::IllegalRequest("Nodes don't belong to the same subnet".to_owned()));
                     }
@@ -924,21 +923,21 @@ mock! {
 
         fn sync_with_nns(&self) -> BoxFuture<'_, anyhow::Result<()>>;
 
-        fn operators(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Operator>>>>;
+        fn operators(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Operator>>>>;
 
-        fn nodes(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Node>>>>;
+        fn nodes(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Node>>>>;
 
         fn firewall_rule_set(&self, firewall_rule_scope: FirewallRulesScope) -> BoxFuture<'_, anyhow::Result<FirewallRuleSet>>;
 
-        fn subnets(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Subnet>>>>;
+        fn subnets(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Subnet>>>>;
 
-        fn nodes_with_proposals(&self) -> BoxFuture<'_, anyhow::Result<Arc<BTreeMap<PrincipalId, Node>>>>;
+        fn nodes_with_proposals(&self) -> BoxFuture<'_, anyhow::Result<Arc<IndexMap<PrincipalId, Node>>>>;
 
         fn unassigned_nodes_replica_version(&self) -> BoxFuture<'_, anyhow::Result<Arc<String>>>;
 
         fn get_api_boundary_nodes(&self) -> anyhow::Result<Vec<(String, ApiBoundaryNodeRecord)>>;
 
-        fn get_node_rewards_table(&self) -> anyhow::Result<BTreeMap<String, NodeRewardsTable>>;
+        fn get_node_rewards_table(&self) -> anyhow::Result<IndexMap<String, NodeRewardsTable>>;
 
         fn get_unassigned_nodes(&self) -> anyhow::Result<Option<UnassignedNodesConfigRecord>>;
 
diff --git a/rs/ic-management-backend/src/registry.rs b/rs/ic-management-backend/src/registry.rs
index 1049510ea..19568ffd6 100644
--- a/rs/ic-management-backend/src/registry.rs
+++ b/rs/ic-management-backend/src/registry.rs
@@ -36,6 +36,7 @@ use ic_registry_local_store::{Changelog, ChangelogEntry, KeyMutation, LocalStore
 use ic_registry_nns_data_provider::registry::RegistryCanister;
 use ic_registry_subnet_type::SubnetType;
 use ic_types::PrincipalId;
+use indexmap::{IndexMap, IndexSet};
 use itertools::Itertools;
 use lazy_static::lazy_static;
 use log::{debug, error, info, warn};
@@ -43,14 +44,11 @@ use regex::Regex;
 use std::cmp::Ordering;
 use std::collections::{HashMap, HashSet};
 use std::convert::TryFrom;
+use std::net::Ipv6Addr;
 use std::ops::Add;
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
 use std::sync::Arc;
-use std::{
-    collections::{BTreeMap, BTreeSet},
-    net::Ipv6Addr,
-};
 use tokio::sync::RwLock;
 use tokio::time::{sleep, Duration};
 use url::Url;
@@ -68,11 +66,11 @@ pub struct RegistryState {
     pub local_registry: Arc<LocalRegistry>,
 
     version: u64,
-    subnets: BTreeMap<PrincipalId, Subnet>,
-    nodes: BTreeMap<PrincipalId, Node>,
-    operators: BTreeMap<PrincipalId, Operator>,
+    subnets: IndexMap<PrincipalId, Subnet>,
+    nodes: IndexMap<PrincipalId, Node>,
+    operators: IndexMap<PrincipalId, Operator>,
     node_labels_guests: Vec<Guest>,
-    known_subnets: BTreeMap<PrincipalId, String>,
+    known_subnets: IndexMap<PrincipalId, String>,
 
     guestos_releases: ArtifactReleases,
     hostos_releases: ArtifactReleases,
@@ -115,13 +113,13 @@ impl RegistryEntry for ApiBoundaryNodeRecord {
 }
 
 pub trait RegistryFamilyEntries {
-    fn get_family_entries<T: RegistryEntry + Default>(&self) -> Result<BTreeMap<String, T>>;
-    fn get_family_entries_versioned<T: RegistryEntry + Default>(&self) -> Result<BTreeMap<String, (u64, T)>>;
-    fn get_family_entries_of_version<T: RegistryEntry + Default>(&self, version: RegistryVersion) -> Result<BTreeMap<String, (u64, T)>>;
+    fn get_family_entries<T: RegistryEntry + Default>(&self) -> Result<IndexMap<String, T>>;
+    fn get_family_entries_versioned<T: RegistryEntry + Default>(&self) -> Result<IndexMap<String, (u64, T)>>;
+    fn get_family_entries_of_version<T: RegistryEntry + Default>(&self, version: RegistryVersion) -> Result<IndexMap<String, (u64, T)>>;
 }
 
 impl RegistryFamilyEntries for LocalRegistry {
-    fn get_family_entries<T: RegistryEntry + Default>(&self) -> Result<BTreeMap<String, T>> {
+    fn get_family_entries<T: RegistryEntry + Default>(&self) -> Result<IndexMap<String, T>> {
         let prefix_length = T::KEY_PREFIX.len();
         Ok(self
             .get_key_family(T::KEY_PREFIX, self.get_latest_version())?
@@ -131,14 +129,14 @@ impl RegistryFamilyEntries for LocalRegistry {
                     .unwrap_or_else(|_| panic!("failed to get entry {} for type {}", key, std::any::type_name::<T>()))
                     .map(|v| (key[prefix_length..].to_string(), T::decode(v.as_slice()).expect("invalid registry value")))
             })
-            .collect::<BTreeMap<_, _>>())
+            .collect::<IndexMap<_, _>>())
     }
 
-    fn get_family_entries_versioned<T: RegistryEntry + Default>(&self) -> Result<BTreeMap<String, (u64, T)>> {
+    fn get_family_entries_versioned<T: RegistryEntry + Default>(&self) -> Result<IndexMap<String, (u64, T)>> {
         self.get_family_entries_of_version(self.get_latest_version())
     }
 
-    fn get_family_entries_of_version<T: RegistryEntry + Default>(&self, version: RegistryVersion) -> Result<BTreeMap<String, (u64, T)>> {
+    fn get_family_entries_of_version<T: RegistryEntry + Default>(&self, version: RegistryVersion) -> Result<IndexMap<String, (u64, T)>> {
         let prefix_length = T::KEY_PREFIX.len();
         Ok(self
             .get_key_family(T::KEY_PREFIX, version)?
@@ -155,7 +153,7 @@ impl RegistryFamilyEntries for LocalRegistry {
                     })
                     .unwrap_or_else(|_| panic!("failed to get entry {} for type {}", key, std::any::type_name::<T>()))
             })
-            .collect::<BTreeMap<_, _>>())
+            .collect::<IndexMap<_, _>>())
     }
 }
 
@@ -218,9 +216,9 @@ impl RegistryState {
             network: network.clone(),
             local_registry,
             version: 0,
-            subnets: BTreeMap::<PrincipalId, Subnet>::new(),
-            nodes: BTreeMap::new(),
-            operators: BTreeMap::new(),
+            subnets: IndexMap::<PrincipalId, Subnet>::new(),
+            nodes: IndexMap::new(),
+            operators: IndexMap::new(),
             node_labels_guests: Vec::new(),
             guestos_releases: ArtifactReleases::new(Artifact::GuestOs),
             hostos_releases: ArtifactReleases::new(Artifact::HostOs),
@@ -386,9 +384,9 @@ impl RegistryState {
     }
 
     fn update_operators(&mut self, providers: &[NodeProviderDetails]) -> Result<()> {
-        let providers = providers.iter().map(|p| (p.principal_id, p)).collect::<BTreeMap<_, _>>();
-        let data_center_records: BTreeMap<String, DataCenterRecord> = self.local_registry.get_family_entries()?;
-        let operator_records: BTreeMap<String, NodeOperatorRecord> = self.local_registry.get_family_entries()?;
+        let providers = providers.iter().map(|p| (p.principal_id, p)).collect::<IndexMap<_, _>>();
+        let data_center_records: IndexMap<String, DataCenterRecord> = self.local_registry.get_family_entries()?;
+        let operator_records: IndexMap<String, NodeOperatorRecord> = self.local_registry.get_family_entries()?;
 
         self.operators = operator_records
             .iter()
@@ -423,7 +421,7 @@ impl RegistryState {
                                 longitude: dc.gps.clone().map(|l| l.longitude as f64),
                             }
                         }),
-                        rewardable_nodes: or.rewardable_nodes.clone(),
+                        rewardable_nodes: or.rewardable_nodes.iter().map(|(k, v)| (k.clone(), *v)).collect(),
                         ipv6: or.ipv6().to_string(),
                     },
                 )
@@ -443,7 +441,7 @@ impl RegistryState {
     fn update_nodes(&mut self) -> Result<()> {
         let node_entries = self.local_registry.get_family_entries_versioned::<NodeRecord>()?;
         let dfinity_dcs = DFINITY_DCS.split(' ').map(|dc| dc.to_string().to_lowercase()).collect::<HashSet<_>>();
-        let api_boundary_nodes: BTreeMap<String, ApiBoundaryNodeRecord> = self.local_registry.get_family_entries()?;
+        let api_boundary_nodes: IndexMap<String, ApiBoundaryNodeRecord> = self.local_registry.get_family_entries()?;
 
         self.nodes = node_entries
             .iter()
@@ -607,15 +605,15 @@ impl RegistryState {
         self.version
     }
 
-    pub fn subnets(&self) -> BTreeMap<PrincipalId, Subnet> {
+    pub fn subnets(&self) -> IndexMap<PrincipalId, Subnet> {
         self.subnets.clone()
     }
 
-    pub fn nodes(&self) -> BTreeMap<PrincipalId, Node> {
+    pub fn nodes(&self) -> IndexMap<PrincipalId, Node> {
         self.nodes.clone()
     }
 
-    pub async fn nodes_with_proposals(&self) -> Result<BTreeMap<PrincipalId, Node>> {
+    pub async fn nodes_with_proposals(&self) -> Result<IndexMap<PrincipalId, Node>> {
         let nodes = self.nodes.clone();
         let proposal_agent = proposal::ProposalAgentImpl::new(self.network.get_nns_urls());
 
@@ -644,7 +642,7 @@ impl RegistryState {
         proposal_agent.list_open_elect_hostos_proposals().await
     }
 
-    pub async fn subnets_with_proposals(&self) -> Result<BTreeMap<PrincipalId, Subnet>> {
+    pub async fn subnets_with_proposals(&self) -> Result<IndexMap<PrincipalId, Subnet>> {
         let subnets = self.subnets.clone();
         let proposal_agent = proposal::ProposalAgentImpl::new(self.network.get_nns_urls());
 
@@ -697,8 +695,8 @@ impl RegistryState {
 
     async fn retireable_hostos_versions(&self) -> Result<Vec<Release>> {
         let active_releases = self.hostos_releases.get_active_branches();
-        let hostos_versions: BTreeSet<String> = self.nodes.values().map(|s| s.hostos_version.clone()).collect();
-        let versions_in_proposals: BTreeSet<String> = self
+        let hostos_versions: IndexSet<String> = self.nodes.values().map(|s| s.hostos_version.clone()).collect();
+        let versions_in_proposals: IndexSet<String> = self
             .open_elect_hostos_proposals()
             .await?
             .iter()
@@ -721,9 +719,9 @@ impl RegistryState {
 
     async fn retireable_guestos_versions(&self) -> Result<Vec<Release>> {
         let active_releases = self.guestos_releases.get_active_branches();
-        let subnet_versions: BTreeSet<String> = self.subnets.values().map(|s| s.replica_version.clone()).collect();
+        let subnet_versions: IndexSet<String> = self.subnets.values().map(|s| s.replica_version.clone()).collect();
         let version_on_unassigned_nodes = self.get_unassigned_nodes_replica_version().await?;
-        let versions_in_proposals: BTreeSet<String> = self
+        let versions_in_proposals: IndexSet<String> = self
             .open_elect_replica_proposals()
             .await?
             .iter()
@@ -754,7 +752,7 @@ impl RegistryState {
         )
     }
 
-    pub fn operators(&self) -> BTreeMap<PrincipalId, Operator> {
+    pub fn operators(&self) -> IndexMap<PrincipalId, Operator> {
         self.operators.clone()
     }
 
@@ -858,7 +856,7 @@ impl SubnetQuerier for RegistryState {
                         .to_vec()
                         .iter()
                         .map(|n| self.nodes.get(&n.id).and_then(|n| n.subnet_id))
-                        .collect::<BTreeSet<_>>();
+                        .collect::<IndexSet<_>>();
                     if subnets.len() > 1 {
                         return Err(NetworkError::IllegalRequest("nodes don't belong to the same subnet".to_string()));
                     }
diff --git a/rs/ic-management-backend/src/release.rs b/rs/ic-management-backend/src/release.rs
index 41b29185a..e1cda437a 100644
--- a/rs/ic-management-backend/src/release.rs
+++ b/rs/ic-management-backend/src/release.rs
@@ -6,10 +6,10 @@ use chrono::{Datelike, NaiveDate, NaiveTime, TimeZone, Utc, Weekday};
 use futures_util::future::try_join_all;
 use ic_management_types::{Network, Release, Subnet};
 use ic_types::PrincipalId;
+use indexmap::{IndexMap, IndexSet};
 use itertools::Itertools;
 use log::info;
 use serde::{Deserialize, Serialize};
-use std::collections::{BTreeMap, BTreeSet};
 use std::str::FromStr;
 use strum_macros::{Display, EnumString};
 
@@ -144,7 +144,7 @@ impl RolloutConfig {
 pub struct RolloutBuilder {
     pub proposal_agent: ProposalAgentImpl,
     pub prometheus_client: prometheus_http_query::Client,
-    pub subnets: BTreeMap<PrincipalId, Subnet>,
+    pub subnets: IndexMap<PrincipalId, Subnet>,
     pub releases: Vec<Release>,
     pub network: Network,
 }
@@ -323,8 +323,8 @@ impl RolloutBuilder {
         });
 
         if let Some(last_stage) = stages.last_mut() {
-            let releases = last_stage.updates.iter().map(|u| u.replica_release.clone()).collect::<BTreeSet<_>>();
-            let mut update_states = BTreeMap::new();
+            let releases = last_stage.updates.iter().map(|u| u.replica_release.clone()).collect::<IndexSet<_>>();
+            let mut update_states = IndexMap::new();
             for release in releases {
                 let release_update_states = get_update_states(&self.network, &self.prometheus_client, &release, last_stage.start_date_time).await?;
                 update_states.insert(release, release_update_states);
@@ -526,7 +526,7 @@ async fn get_update_states(
     prometheus_client: &prometheus_http_query::Client,
     release: &Release,
     since: chrono::DateTime<Utc>,
-) -> Result<BTreeMap<PrincipalId, SubnetUpdateState>> {
+) -> Result<IndexMap<PrincipalId, SubnetUpdateState>> {
     const STATE_FIELD: &str = "state";
     let query = format!(
         r#"
@@ -624,7 +624,7 @@ pub async fn list_subnets_release_statuses(
     proposal_agent: &ProposalAgentImpl,
     prometheus_client: &prometheus_http_query::Client,
     network: Network,
-    subnets: BTreeMap<PrincipalId, Subnet>,
+    subnets: IndexMap<PrincipalId, Subnet>,
     releases: Vec<Release>,
 ) -> anyhow::Result<Vec<SubnetUpdate>> {
     let mut subnet_update_proposals = proposal_agent.list_update_subnet_version_proposals().await?;
@@ -633,7 +633,7 @@ pub async fn list_subnets_release_statuses(
     let latest_updates = subnets
         .keys()
         .map(|p| (p, subnet_update_proposals.iter().find(|sup| sup.payload.subnet_id == *p)))
-        .collect::<BTreeMap<_, _>>();
+        .collect::<IndexMap<_, _>>();
 
     let active_releases = latest_updates
         .values()
@@ -658,7 +658,7 @@ pub async fn list_subnets_release_statuses(
                     .unwrap_or_else(Utc::now),
             )
         })
-        .collect::<BTreeMap<_, _>>();
+        .collect::<IndexMap<_, _>>();
 
     let updates_statuses_for_revision = try_join_all(active_releases.clone().into_iter().cloned().map(|r| async {
         let retryable = || async {
@@ -677,7 +677,7 @@ pub async fn list_subnets_release_statuses(
     }))
     .await?
     .into_iter()
-    .collect::<BTreeMap<_, _>>();
+    .collect::<IndexMap<_, _>>();
 
     let latest_releases = releases.iter().rev().unique_by(|r| r.branch.clone()).collect::<Vec<_>>();
 
diff --git a/rs/ic-management-backend/src/subnets.rs b/rs/ic-management-backend/src/subnets.rs
index b94bf88a1..9cf68a5ea 100644
--- a/rs/ic-management-backend/src/subnets.rs
+++ b/rs/ic-management-backend/src/subnets.rs
@@ -1,11 +1,10 @@
-use std::collections::BTreeMap;
-
 use decentralization::{network::SubnetChange, SubnetChangeResponse};
 use ic_base_types::PrincipalId;
 use ic_management_types::{Node, TopologyChangeProposal};
+use indexmap::IndexMap;
 
 pub fn get_proposed_subnet_changes(
-    all_nodes: &BTreeMap<PrincipalId, Node>,
+    all_nodes: &IndexMap<PrincipalId, Node>,
     subnet: &ic_management_types::Subnet,
 ) -> Result<SubnetChangeResponse, anyhow::Error> {
     if let Some(proposal) = &subnet.proposal {
@@ -125,8 +124,8 @@ mod tests {
         assert_eq!(change.removed_with_desc.iter().map(|x| x.0).collect::<Vec<_>>(), node_ids_removed);
     }
 
-    fn gen_test_nodes(subnet_id: PrincipalId, num_nodes: u64, start_at_number: u64) -> BTreeMap<PrincipalId, Node> {
-        let mut nodes = BTreeMap::new();
+    fn gen_test_nodes(subnet_id: PrincipalId, num_nodes: u64, start_at_number: u64) -> IndexMap<PrincipalId, Node> {
+        let mut nodes = IndexMap::new();
         for i in start_at_number..start_at_number + num_nodes {
             let node = Node {
                 principal: PrincipalId::new_node_test_id(i),
diff --git a/rs/ic-management-types/Cargo.toml b/rs/ic-management-types/Cargo.toml
index 7f0889e71..799a8f05d 100644
--- a/rs/ic-management-types/Cargo.toml
+++ b/rs/ic-management-types/Cargo.toml
@@ -15,6 +15,7 @@ ic-base-types = { workspace = true }
 ic-nns-governance = { workspace = true }
 ic-registry-subnet-type = { workspace = true }
 ic-types = { workspace = true }
+indexmap = { workspace = true }
 registry-canister = { workspace = true }
 reqwest = { workspace = true }
 serde = { workspace = true }
diff --git a/rs/np-notifications/Cargo.toml b/rs/np-notifications/Cargo.toml
index 45aff305c..2f4d01ab3 100644
--- a/rs/np-notifications/Cargo.toml
+++ b/rs/np-notifications/Cargo.toml
@@ -16,6 +16,7 @@ clap = { workspace = true }
 ic-management-backend = { path = "../ic-management-backend" }
 ic-management-types = { path = "../ic-management-types" }
 ic-types = { workspace = true }
+indexmap = { workspace = true }
 rand = { workspace = true }
 reqwest = { workspace = true }
 serde = { workspace = true }
diff --git a/rs/np-notifications/src/nodes_status.rs b/rs/np-notifications/src/nodes_status.rs
index 6c327c5c2..5b3bb013b 100644
--- a/rs/np-notifications/src/nodes_status.rs
+++ b/rs/np-notifications/src/nodes_status.rs
@@ -1,27 +1,39 @@
-use std::collections::{BTreeMap, BTreeSet};
+use indexmap::{IndexMap, IndexSet};
 
 use ic_management_types::HealthStatus;
 use ic_types::PrincipalId;
 
 use crate::notification::Notification;
 
-#[derive(Debug, PartialOrd, Ord, PartialEq, Eq, Clone)]
+#[derive(Debug, PartialEq, Eq, Clone)]
 pub struct NodesStatus {
-    nodes: BTreeMap<PrincipalId, HealthStatus>,
+    nodes: IndexMap<PrincipalId, HealthStatus>,
 }
 
-impl From<BTreeMap<PrincipalId, HealthStatus>> for NodesStatus {
-    fn from(tree: BTreeMap<PrincipalId, HealthStatus>) -> Self {
+impl Ord for NodesStatus {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.nodes.iter().cmp(&other.nodes)
+    }
+}
+
+impl PartialOrd for NodesStatus {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+impl From<IndexMap<PrincipalId, HealthStatus>> for NodesStatus {
+    fn from(tree: IndexMap<PrincipalId, HealthStatus>) -> Self {
         Self { nodes: tree }
     }
 }
 
 impl NodesStatus {
     pub fn _new() -> Self {
-        Self { nodes: BTreeMap::new() }
+        Self { nodes: IndexMap::new() }
     }
 
-    pub fn get_set_of_node_ids(&self) -> BTreeSet<PrincipalId> {
+    pub fn get_set_of_node_ids(&self) -> IndexSet<PrincipalId> {
         self.nodes.keys().copied().collect()
     }
 
@@ -29,7 +41,7 @@ impl NodesStatus {
         self.nodes.get(&id)
     }
 
-    pub fn updated_from_map(&self, map: BTreeMap<PrincipalId, HealthStatus>) -> (NodesStatus, Vec<Notification>) {
+    pub fn updated_from_map(&self, map: IndexMap<PrincipalId, HealthStatus>) -> (NodesStatus, Vec<Notification>) {
         self.updated(Self::from(map))
     }
 
@@ -43,7 +55,7 @@ impl NodesStatus {
         let current_status_node_ids = self.get_set_of_node_ids();
         let new_status_node_ids = new_statuses.get_set_of_node_ids();
 
-        let added_nodes: BTreeSet<PrincipalId> = new_status_node_ids.difference(&current_status_node_ids).cloned().collect();
+        let added_nodes: IndexSet<PrincipalId> = new_status_node_ids.difference(&current_status_node_ids).cloned().collect();
 
         for node_id in added_nodes {
             notifications.push(Notification {
@@ -59,7 +71,7 @@ impl NodesStatus {
             })
         }
 
-        let removed_nodes: BTreeSet<PrincipalId> = current_status_node_ids.difference(&new_status_node_ids).cloned().collect();
+        let removed_nodes: IndexSet<PrincipalId> = current_status_node_ids.difference(&new_status_node_ids).cloned().collect();
 
         for node_id in removed_nodes {
             notifications.push(Notification {
@@ -74,7 +86,7 @@ impl NodesStatus {
             })
         }
 
-        let kept_nodes: BTreeSet<PrincipalId> = current_status_node_ids.intersection(&new_status_node_ids).cloned().collect();
+        let kept_nodes: IndexSet<PrincipalId> = current_status_node_ids.intersection(&new_status_node_ids).cloned().collect();
 
         for node_id in kept_nodes {
             if self.get(node_id) != new_statuses.get(node_id) {
@@ -120,14 +132,14 @@ mod tests {
         ];
 
         let statuses = NodesStatus {
-            nodes: BTreeMap::from([
+            nodes: IndexMap::from([
                 (ids[0], HealthStatus::Healthy),
                 (ids[1], HealthStatus::Healthy),
                 (ids[2], HealthStatus::Healthy),
             ]),
         };
         let new_statuses = NodesStatus {
-            nodes: BTreeMap::from([
+            nodes: IndexMap::from([
                 (ids[0], HealthStatus::Healthy),
                 (ids[1], HealthStatus::Degraded),
                 (ids[3], HealthStatus::Healthy),