diff --git a/proto/src/main/protobuf/bosatsu/TypedAst.proto b/proto/src/main/protobuf/bosatsu/TypedAst.proto
index 2ea07d050..af7d5624d 100644
--- a/proto/src/main/protobuf/bosatsu/TypedAst.proto
+++ b/proto/src/main/protobuf/bosatsu/TypedAst.proto
@@ -327,3 +327,59 @@ message Package {
 message Packages {
   repeated Package packages = 1;
 }
+
+// Message representing a Version using Semantic Versioning
+message Version {
+  int64 major = 1;
+  int64 minor = 2;
+  int64 patch = 3;
+  string pre_release = 4;
+  string build = 5;
+}
+
+// Message representing a Descriptor for versioning and identification
+message LibDescriptor {
+  Version version = 1;          // Semantic versioning information
+  repeated string hashes = 2;   // List of relevant hashes for verification
+  repeated string uris = 3;     // URIs where the dependency can be obtained
+}
+
+// Message representing the history of versions for a Library or Dependency
+message LibHistory {
+  LibDescriptor previous_patch = 1;  // Descriptor for the previous patch version, if any
+  LibDescriptor previous_minor = 2;  // Descriptor for the previous minor version, if any
+  LibDescriptor previous_major = 3;  // Descriptor for the previous major version, if any
+  LibDescriptor previous_prerelease = 4; // Descriptor for the previous prerelease if any
+  repeated LibDescriptor others = 5; // Some links to other previous versions to improve navigation speed
+}
+
+// Message representing a Dependency on another Library
+message LibDependency {
+  string name = 1;               // Name of the dependent library
+  LibDescriptor desc = 2;           // Descriptor of the dependent library (must have non-empty hashes)
+}
+
+// Message representing a Library
+message Library {
+  string name = 1;
+  int32 depth = 2;              // Depth in the dependency graph
+  string vcs_indent = 3;        // Version control system identifier (e.g., git:commit:aae)
+  string repo_uri = 4;          // canonical repo for the this library at this version
+  LibDescriptor descriptor = 5; // Contains versioning and identification info
+
+  // Exported interfaces that other libraries can use
+  repeated Interface exported_ifaces = 6;
+
+  // Internal packages within the library
+  repeated Package internal_packages = 7;
+
+  // Public dependencies that are exposed to consumers of this library
+  repeated LibDependency public_dependencies = 8;
+
+  // Private dependencies used internally by the library
+  repeated LibDependency private_dependencies = 9;
+
+  // Historical versions of the library
+  LibHistory history = 10;
+}
+