diff --git a/checkpoint.json b/checkpoint.json
index 44402fd5c..a4b6b762b 100644
--- a/checkpoint.json
+++ b/checkpoint.json
@@ -1,38 +1,45 @@
 {
-  "timestamp": "2026-03-15T16:13:00.237684Z",
-  "current_node": "preflight_lint",
+  "timestamp": "2026-03-15T16:13:00.283339Z",
+  "current_node": "implement",
   "completed_nodes": [
     "start",
     "toolchain",
     "preflight_compile",
-    "preflight_lint"
+    "preflight_lint",
+    "implement"
   ],
   "node_retries": {
     "toolchain": 1,
     "preflight_compile": 1,
     "preflight_lint": 1,
+    "implement": 1,
     "start": 1
   },
   "context_values": {
     "graph.rankdir": "LR",
+    "thread.preflight_lint.current_node": "implement",
     "thread.toolchain.current_node": "preflight_compile",
+    "last_stage": "implement",
     "failure_signature": "",
     "thread.preflight_compile.current_node": "preflight_lint",
     "internal.run_id": "01KKS4BBSZPJ99MET7VT4TGFKY",
     "thread.start.current_node": "toolchain",
     "command.stderr": "",
     "internal.retry_count.preflight_lint": 1,
+    "internal.retry_count.implement": 1,
     "outcome": "success",
     "internal.retry_count.start": 1,
     "failure_class": "",
     "internal.work_dir": "/Users/bhelmkamp/.fabro/runs/20260315-01KKS4BBSZPJ99MET7VT4TGFKY/worktree",
+    "response.implement": "[Simulated] Response for stage: implement",
     "graph.model_stylesheet": "\n            * { backend: api; model: claude-opus-4-6;}\n        ",
-    "current_node": "preflight_lint",
+    "current_node": "implement",
     "command.output": "",
     "internal.retry_count.preflight_compile": 1,
     "internal.retry_count.toolchain": 1,
-    "internal.thread_id": "preflight_compile",
-    "current.preamble": "Goal: Implement and simplify\n\n## Completed stages\n- **toolchain**: success\n  - Script: `command -v cargo >/dev/null || { curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y && sudo ln -sf $HOME/.cargo/bin/* /usr/local/bin/; }; cargo --version 2>&1`\n  - Stdout: (empty)\n  - Stderr: (empty)\n- **preflight_compile**: success\n  - Script: `cargo check 2>&1`\n  - Stdout: (empty)\n  - Stderr: (empty)\n",
+    "internal.thread_id": "preflight_lint",
+    "last_response": "[Simulated] Response for stage: implement",
+    "current.preamble": "Goal: Implement and simplify\n\n## Completed stages\n- **toolchain**: success\n  - Script: `command -v cargo >/dev/null || { curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y && sudo ln -sf $HOME/.cargo/bin/* /usr/local/bin/; }; cargo --version 2>&1`\n  - Stdout: (empty)\n  - Stderr: (empty)\n- **preflight_compile**: success\n  - Script: `cargo check 2>&1`\n  - Stdout: (empty)\n  - Stderr: (empty)\n- **preflight_lint**: success\n  - Script: `cargo clippy -- -D warnings 2>&1`\n  - Stdout: (empty)\n  - Stderr: (empty)\n",
     "graph.goal": "Implement and simplify",
     "internal.node_visit_count": 1,
     "internal.fidelity": "compact"
@@ -69,11 +76,22 @@
     "start": {
       "status": "success",
       "duration_ms": 0
+    },
+    "implement": {
+      "status": "success",
+      "context_updates": {
+        "response.implement": "[Simulated] Response for stage: implement",
+        "last_response": "[Simulated] Response for stage: implement",
+        "last_stage": "implement"
+      },
+      "notes": "Stage completed: implement",
+      "duration_ms": 3
     }
   },
-  "next_node_id": "implement",
+  "next_node_id": "simplify",
   "node_visits": {
     "preflight_lint": 1,
+    "implement": 1,
     "start": 1,
     "toolchain": 1,
     "preflight_compile": 1
diff --git a/nodes/implement/prompt.md b/nodes/implement/prompt.md
new file mode 100644
index 000000000..b492f53d6
--- /dev/null
+++ b/nodes/implement/prompt.md
@@ -0,0 +1,18 @@
+Goal: Implement and simplify
+
+## Completed stages
+- **toolchain**: success
+  - Script: `command -v cargo >/dev/null || { curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y && sudo ln -sf $HOME/.cargo/bin/* /usr/local/bin/; }; cargo --version 2>&1`
+  - Stdout: (empty)
+  - Stderr: (empty)
+- **preflight_compile**: success
+  - Script: `cargo check 2>&1`
+  - Stdout: (empty)
+  - Stderr: (empty)
+- **preflight_lint**: success
+  - Script: `cargo clippy -- -D warnings 2>&1`
+  - Stdout: (empty)
+  - Stderr: (empty)
+
+
+Read the plan file referenced in the goal and implement every step. Make all the code changes described in the plan.
\ No newline at end of file
diff --git a/nodes/implement/response.md b/nodes/implement/response.md
new file mode 100644
index 000000000..09359b881
--- /dev/null
+++ b/nodes/implement/response.md
@@ -0,0 +1 @@
+[Simulated] Response for stage: implement
\ No newline at end of file
diff --git a/nodes/implement/status.json b/nodes/implement/status.json
new file mode 100644
index 000000000..52bc4d7f9
--- /dev/null
+++ b/nodes/implement/status.json
@@ -0,0 +1,6 @@
+{
+  "status": "success",
+  "notes": "Stage completed: implement",
+  "failure_reason": null,
+  "timestamp": "2026-03-15T16:13:00.283045+00:00"
+}
\ No newline at end of file