diff --git a/rust/private/extensions.bzl b/rust/private/extensions.bzl
new file mode 100644
index 0000000..05f9076
--- /dev/null
+++ b/rust/private/extensions.bzl
@@ -0,0 +1,12 @@
+"""Bzlmod module extensions that are only used internally"""
+
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+load("//rust/private:repository_utils.bzl", "TINYJSON_KWARGS")
+
+def _internal_deps_impl(_module_ctx):
+    http_archive(**TINYJSON_KWARGS)
+
+internal_deps = module_extension(
+    doc = "Dependencies for rules_rust",
+    implementation = _internal_deps_impl,
+)