diff --git a/adapters/terraform/adapter.py b/adapters/terraform/adapter.py
index bf0a591..a54cfe3 100644
--- a/adapters/terraform/adapter.py
+++ b/adapters/terraform/adapter.py
@@ -82,6 +82,8 @@ def adapt(ir_instance, out_dir):
     )
 
     # --- terraform.tf: required_version + required_providers + S3 backend (no DynamoDB lock per D-P09-1) ---
+    # The backend key is derived from the stack name so l1 vs l2 spikes use separate state keys (D-P10-1).
+    stack_name = stack.get("name", "spike")
     terraform_tf = (
         'terraform {\n'
         '  required_version = ">= 1.9, < 1.10"\n'
@@ -93,7 +95,7 @@ def adapt(ir_instance, out_dir):
         '  }\n'
         '  backend "s3" {\n'
         '    bucket = "acdl-tfstate-581513795199-us-east-1"\n'
-        '    key    = "spike/l1-s3/terraform.tfstate"\n'
+        f'    key    = "spike/{stack_name}/terraform.tfstate"\n'
         '    region = "us-east-1"\n'
         '  }\n'
         '}\n'
diff --git a/modules-ir/l2/l2-static-asset/README.md b/modules-ir/l2/l2-static-asset/README.md
new file mode 100644
index 0000000..f13dc00
--- /dev/null
+++ b/modules-ir/l2/l2-static-asset/README.md
@@ -0,0 +1,31 @@
+# l2-static-asset — thin-composition (S3 static asset)
+
+The v1.1 spike's L2. A thin-composition that references `l1-s3` only
+(depth 1). The contract's inputs (`bucket_name`, `region`) map 1:1
+through the wires to the L1's inputs.
+
+## Composition (the IR-typed thin-composition tree)
+
+See `composition.json`: `kind=l2`, `depth=1`, one child `l1-s3@1.0.0`,
+wires `{bucket_name → s3.inputs.bucket_name, region → s3.inputs.region}`
+(passthrough).
+
+## IR → Terraform mapping (D-P10-1)
+
+The Terraform adapter consumes the *resolved IR instance* (which has
+`kind=l2` + the L1 resource `s3` in its `resources` array). For a
+depth-1 thin-composition, the L2 root module **IS** the L1's resource —
+no separate `module "l1_s3" { source = "..." }` block. The existing
+adapter `TYPE_MAP` + resource emission handle both l1 and l2 instances
+(the resources array is the same shape). The `relationships` array is
+ignored at the Terraform level for the spike (composition ordering is
+implicit in the single resource).
+
+v1.2 may emit a real `module "l1_s3" { source = "..." }` block when L1s
+become published Terraform modules rather than inline resources.
+
+## Versioning (W3.D)
+
+`1.0.0` — interface MAJOR, behavior MINOR, lifecycle PATCH. MAJOR bumps
+require a new registry entry (immutable publication); old entries enter
+a 12-month deprecation window.
\ No newline at end of file
diff --git a/modules-ir/l2/l2-static-asset/composition.json b/modules-ir/l2/l2-static-asset/composition.json
new file mode 100644
index 0000000..e24f092
--- /dev/null
+++ b/modules-ir/l2/l2-static-asset/composition.json
@@ -0,0 +1,17 @@
+{
+  "name": "l2-static-asset",
+  "version": "1.0.0",
+  "kind": "l2",
+  "depth": 1,
+  "description": "Thin-composition: a single S3 bucket for static asset hosting. References l1-s3 only (depth 1).",
+  "children": [
+    {
+      "id": "s3",
+      "module": "l1-s3@1.0.0"
+    }
+  ],
+  "wires": {
+    "bucket_name": {"target": "s3", "input": "bucket_name"},
+    "region": {"target": "s3", "input": "region"}
+  }
+}
\ No newline at end of file
diff --git a/modules-ir/registry.json b/modules-ir/registry.json
index 9c480bd..444da98 100644
--- a/modules-ir/registry.json
+++ b/modules-ir/registry.json
@@ -5,5 +5,12 @@
       "published_at": "2026-07-21T19:00:00Z",
       "deprecated": false
     }
+  },
+  "l2-static-asset": {
+    "1.0.0": {
+      "composition": "modules-ir/l2/l2-static-asset/composition.json",
+      "published_at": "2026-07-21T19:30:00Z",
+      "deprecated": false
+    }
   }
 }
\ No newline at end of file