diff --git a/packages/client/hmi-client/src/types/Types.ts b/packages/client/hmi-client/src/types/Types.ts
index 89088e6343..42e74af22c 100644
--- a/packages/client/hmi-client/src/types/Types.ts
+++ b/packages/client/hmi-client/src/types/Types.ts
@@ -266,6 +266,38 @@ export interface TypingSemantics {
     system: any;
 }
 
+export interface DecapodesComponent {
+    modelInterface: string[];
+    model: DecapodesExpression;
+    _type: string;
+}
+
+export interface DecapodesEquation {
+    lhs: any;
+    rhs: any;
+    _type: string;
+}
+
+export interface DecapodesExpression {
+    context: any[];
+    equations: DecapodesEquation[];
+    _type: string;
+}
+
+export interface DecapodesTerm {
+    name?: string;
+    var?: DecapodesTerm;
+    symbol?: string;
+    space?: string;
+    fs?: string[];
+    arg?: DecapodesTerm;
+    f?: string;
+    arg1?: DecapodesTerm;
+    arg2?: DecapodesTerm;
+    args?: DecapodesTerm[];
+    _type: string;
+}
+
 export interface PetriNetModel {
     states: PetriNetState[];
     transitions: PetriNetTransition[];
diff --git a/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesComponent.java b/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesComponent.java
new file mode 100644
index 0000000000..3c1ceffd62
--- /dev/null
+++ b/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesComponent.java
@@ -0,0 +1,17 @@
+package software.uncharted.terarium.hmiserver.models.dataservice.multiphysics;
+
+import lombok.Data;
+import lombok.experimental.Accessors;
+import software.uncharted.terarium.hmiserver.annotations.TSModel;
+import com.fasterxml.jackson.annotation.JsonAlias;
+import java.util.List;
+
+@Data
+@Accessors(chain = true)
+@TSModel
+public class DecapodesComponent {
+	@JsonAlias("interface")
+	private List<String> modelInterface;
+	private DecapodesExpression model;
+	private String _type;
+}
diff --git a/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesEquation.java b/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesEquation.java
new file mode 100644
index 0000000000..b9d117edfb
--- /dev/null
+++ b/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesEquation.java
@@ -0,0 +1,14 @@
+package software.uncharted.terarium.hmiserver.models.dataservice.multiphysics;
+
+import lombok.Data;
+import lombok.experimental.Accessors;
+import software.uncharted.terarium.hmiserver.annotations.TSModel;
+
+@Data
+@Accessors(chain = true)
+@TSModel
+public class DecapodesEquation {
+	private Object lhs;
+	private Object rhs;
+	private String _type;
+}
diff --git a/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesExpression.java b/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesExpression.java
new file mode 100644
index 0000000000..6d7a2e2eca
--- /dev/null
+++ b/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesExpression.java
@@ -0,0 +1,21 @@
+package software.uncharted.terarium.hmiserver.models.dataservice.multiphysics;
+
+import lombok.Data;
+import lombok.experimental.Accessors;
+import software.uncharted.terarium.hmiserver.annotations.TSModel;
+import java.util.List;
+
+/**
+ * See
+ * https://algebraicjulia.github.io/SyntacticModels.jl/dev/generated/composite_models_examples/#Specifying-the-Component-Systems
+ * https://algebraicjulia.github.io/SyntacticModels.jl/dev/generated/decapodes_examples/
+**/
+
+@Data
+@Accessors(chain = true)
+@TSModel
+public class DecapodesExpression {
+	private List<Object> context;
+	private List<DecapodesEquation> equations;
+	private String _type;
+}
diff --git a/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesTerm.java b/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesTerm.java
new file mode 100644
index 0000000000..fec85689ac
--- /dev/null
+++ b/packages/server/src/main/java/software/uncharted/terarium/hmiserver/models/dataservice/multiphysics/DecapodesTerm.java
@@ -0,0 +1,64 @@
+package software.uncharted.terarium.hmiserver.models.dataservice.multiphysics;
+
+import lombok.Data;
+import lombok.experimental.Accessors;
+import software.uncharted.terarium.hmiserver.annotations.TSModel;
+import software.uncharted.terarium.hmiserver.annotations.TSOptional;
+
+import java.util.List;
+
+//////
+// Note: Decapode term can be one of many different types. As in
+// term = A or B or C or ... wher A, B, C, D ... are different objects.
+//
+// Since Java does not have type-disjunctions this is represented as a
+// union of all the known types. See below
+//
+// October 2023:
+//   Var(name::Symbol)
+//   Lit(name::Symbol)
+//   Judgement(var::Var, dim::Symbol, space::Symbol)
+//   AppCirc1(fs::Vector{Symbol}, arg::Term)
+//   App1(f::Symbol, arg::Term)
+//   App2(f::Symbol, arg1::Term, arg2::Term)
+//   Plus(args::Vector{Term})
+//   Mult(args::Vector{Term})
+//   Tan(var::Term)
+//////
+
+@Data
+@Accessors(chain = true)
+@TSModel
+public class DecapodesTerm {
+	@TSOptional
+	private String name;
+
+	@TSOptional
+	private DecapodesTerm var;
+
+	@TSOptional
+	private String symbol;
+
+	@TSOptional
+	private String space;
+
+	@TSOptional
+	private List<String> fs;
+
+	@TSOptional
+	private DecapodesTerm arg;
+
+	@TSOptional
+	private String f;
+
+	@TSOptional
+	private DecapodesTerm arg1;
+
+	@TSOptional
+	private DecapodesTerm arg2;
+
+	@TSOptional
+	private List<DecapodesTerm> args;
+
+	private String _type;
+}