diff --git a/.agents/hooks.json b/.agents/hooks.json
index f7b02da4..1cc75fb6 100644
--- a/.agents/hooks.json
+++ b/.agents/hooks.json
@@ -6,7 +6,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook PreToolUse --cli antigravity",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PreToolUse --cli antigravity",
             "timeout": 30,
             "__failproofai_hook__": true
           }
@@ -19,7 +19,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook PostToolUse --cli antigravity",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PostToolUse --cli antigravity",
             "timeout": 30,
             "__failproofai_hook__": true
           }
@@ -29,7 +29,7 @@
     "PreInvocation": [
       {
         "type": "command",
-        "command": "bun bin/failproofai.mjs --hook PreInvocation --cli antigravity",
+        "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PreInvocation --cli antigravity",
         "timeout": 30,
         "__failproofai_hook__": true
       }
@@ -37,7 +37,7 @@
     "Stop": [
       {
         "type": "command",
-        "command": "bun bin/failproofai.mjs --hook Stop --cli antigravity",
+        "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 1; }; node scripts/dev-hook.mjs --hook Stop --cli antigravity",
         "timeout": 30,
         "__failproofai_hook__": true
       }
diff --git a/.agents/plugins/failproofai/hooks/hooks.json b/.agents/plugins/failproofai/hooks/hooks.json
index 3e01bf19..db51f6a1 100644
--- a/.agents/plugins/failproofai/hooks/hooks.json
+++ b/.agents/plugins/failproofai/hooks/hooks.json
@@ -5,7 +5,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook SessionStart --cli goose"
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook SessionStart --cli goose"
           }
         ]
       }
@@ -15,7 +15,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook UserPromptSubmit --cli goose"
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook UserPromptSubmit --cli goose"
           }
         ]
       }
@@ -25,7 +25,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook PreToolUse --cli goose"
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PreToolUse --cli goose"
           }
         ]
       }
@@ -35,7 +35,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook PostToolUse --cli goose"
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PostToolUse --cli goose"
           }
         ]
       }
@@ -45,7 +45,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook SessionEnd --cli goose"
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook SessionEnd --cli goose"
           }
         ]
       }
diff --git a/.claude/settings.json b/.claude/settings.json
index fe134c20..573c48b5 100644
--- a/.claude/settings.json
+++ b/.claude/settings.json
@@ -5,7 +5,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook SessionStart",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook SessionStart",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -17,7 +17,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook SessionEnd",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook SessionEnd",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -29,7 +29,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook UserPromptSubmit",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook UserPromptSubmit",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -41,7 +41,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook PreToolUse",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook PreToolUse",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -53,7 +53,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook PermissionRequest",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook PermissionRequest",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -65,7 +65,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook PermissionDenied",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook PermissionDenied",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -77,7 +77,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook PostToolUse",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook PostToolUse",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -89,7 +89,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook PostToolUseFailure",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook PostToolUseFailure",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -101,7 +101,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook Notification",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook Notification",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -113,7 +113,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook SubagentStart",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook SubagentStart",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -125,7 +125,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook SubagentStop",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 1; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook SubagentStop",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -137,7 +137,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook TaskCreated",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook TaskCreated",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -149,7 +149,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook TaskCompleted",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook TaskCompleted",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -161,7 +161,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook Stop",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 1; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook Stop",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -173,7 +173,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook StopFailure",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 1; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook StopFailure",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -185,7 +185,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook TeammateIdle",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook TeammateIdle",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -197,7 +197,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook InstructionsLoaded",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook InstructionsLoaded",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -209,7 +209,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook ConfigChange",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook ConfigChange",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -221,7 +221,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook CwdChanged",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook CwdChanged",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -233,7 +233,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook FileChanged",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook FileChanged",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -245,7 +245,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook WorktreeCreate",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook WorktreeCreate",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -257,7 +257,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook WorktreeRemove",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook WorktreeRemove",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -269,7 +269,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook PreCompact",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook PreCompact",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -281,7 +281,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook PostCompact",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook PostCompact",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -293,7 +293,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook Elicitation",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook Elicitation",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -305,7 +305,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook ElicitationResult",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node \"$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs\" --hook ElicitationResult",
             "timeout": 60,
             "__failproofai_hook__": true
           }
diff --git a/.codex/hooks.json b/.codex/hooks.json
index 20bc2fc8..9afb9e63 100644
--- a/.codex/hooks.json
+++ b/.codex/hooks.json
@@ -5,7 +5,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook SessionStart --cli codex",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook SessionStart --cli codex",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -17,7 +17,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook PreToolUse --cli codex",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PreToolUse --cli codex",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -29,7 +29,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook PermissionRequest --cli codex",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PermissionRequest --cli codex",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -41,7 +41,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook PostToolUse --cli codex",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PostToolUse --cli codex",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -53,7 +53,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook UserPromptSubmit --cli codex",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook UserPromptSubmit --cli codex",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -65,7 +65,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook Stop --cli codex",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 1; }; node scripts/dev-hook.mjs --hook Stop --cli codex",
             "timeout": 60,
             "__failproofai_hook__": true
           }
diff --git a/.cursor/hooks.json b/.cursor/hooks.json
index 395bb640..cfa821d7 100644
--- a/.cursor/hooks.json
+++ b/.cursor/hooks.json
@@ -4,42 +4,42 @@
     "sessionStart": [
       {
         "type": "command",
-        "command": "bun bin/failproofai.mjs --hook sessionStart --cli cursor",
+        "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook sessionStart --cli cursor",
         "timeout": 60
       }
     ],
     "sessionEnd": [
       {
         "type": "command",
-        "command": "bun bin/failproofai.mjs --hook sessionEnd --cli cursor",
+        "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook sessionEnd --cli cursor",
         "timeout": 60
       }
     ],
     "beforeSubmitPrompt": [
       {
         "type": "command",
-        "command": "bun bin/failproofai.mjs --hook beforeSubmitPrompt --cli cursor",
+        "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook beforeSubmitPrompt --cli cursor",
         "timeout": 60
       }
     ],
     "preToolUse": [
       {
         "type": "command",
-        "command": "bun bin/failproofai.mjs --hook preToolUse --cli cursor",
+        "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook preToolUse --cli cursor",
         "timeout": 60
       }
     ],
     "postToolUse": [
       {
         "type": "command",
-        "command": "bun bin/failproofai.mjs --hook postToolUse --cli cursor",
+        "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook postToolUse --cli cursor",
         "timeout": 60
       }
     ],
     "stop": [
       {
         "type": "command",
-        "command": "bun bin/failproofai.mjs --hook stop --cli cursor",
+        "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 1; }; node scripts/dev-hook.mjs --hook stop --cli cursor",
         "timeout": 60
       }
     ]
diff --git a/.devin/config.json b/.devin/config.json
index 3b311ccd..4f6a3c78 100644
--- a/.devin/config.json
+++ b/.devin/config.json
@@ -5,7 +5,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook SessionStart --cli devin",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook SessionStart --cli devin",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -17,7 +17,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook UserPromptSubmit --cli devin",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook UserPromptSubmit --cli devin",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -29,7 +29,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook PreToolUse --cli devin",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PreToolUse --cli devin",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -41,7 +41,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook PostToolUse --cli devin",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PostToolUse --cli devin",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -53,7 +53,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook PermissionRequest --cli devin",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PermissionRequest --cli devin",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -65,7 +65,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook Stop --cli devin",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 1; }; node scripts/dev-hook.mjs --hook Stop --cli devin",
             "timeout": 60,
             "__failproofai_hook__": true
           }
@@ -77,7 +77,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "bun bin/failproofai.mjs --hook SessionEnd --cli devin",
+            "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook SessionEnd --cli devin",
             "timeout": 60,
             "__failproofai_hook__": true
           }
diff --git a/.factory/hooks.json b/.factory/hooks.json
index b2fa3660..1677c14b 100644
--- a/.factory/hooks.json
+++ b/.factory/hooks.json
@@ -4,7 +4,7 @@
       "hooks": [
         {
           "type": "command",
-          "command": "bun bin/failproofai.mjs --hook SessionStart --cli factory",
+          "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook SessionStart --cli factory",
           "timeout": 30,
           "__failproofai_hook__": true
         }
@@ -16,7 +16,7 @@
       "hooks": [
         {
           "type": "command",
-          "command": "bun bin/failproofai.mjs --hook UserPromptSubmit --cli factory",
+          "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook UserPromptSubmit --cli factory",
           "timeout": 30,
           "__failproofai_hook__": true
         }
@@ -29,7 +29,7 @@
       "hooks": [
         {
           "type": "command",
-          "command": "bun bin/failproofai.mjs --hook PreToolUse --cli factory",
+          "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PreToolUse --cli factory",
           "timeout": 30,
           "__failproofai_hook__": true
         }
@@ -42,7 +42,7 @@
       "hooks": [
         {
           "type": "command",
-          "command": "bun bin/failproofai.mjs --hook PostToolUse --cli factory",
+          "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PostToolUse --cli factory",
           "timeout": 30,
           "__failproofai_hook__": true
         }
@@ -54,7 +54,7 @@
       "hooks": [
         {
           "type": "command",
-          "command": "bun bin/failproofai.mjs --hook Notification --cli factory",
+          "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook Notification --cli factory",
           "timeout": 30,
           "__failproofai_hook__": true
         }
@@ -66,7 +66,7 @@
       "hooks": [
         {
           "type": "command",
-          "command": "bun bin/failproofai.mjs --hook Stop --cli factory",
+          "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 1; }; node scripts/dev-hook.mjs --hook Stop --cli factory",
           "timeout": 30,
           "__failproofai_hook__": true
         }
@@ -78,7 +78,7 @@
       "hooks": [
         {
           "type": "command",
-          "command": "bun bin/failproofai.mjs --hook SubagentStop --cli factory",
+          "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 1; }; node scripts/dev-hook.mjs --hook SubagentStop --cli factory",
           "timeout": 30,
           "__failproofai_hook__": true
         }
@@ -90,7 +90,7 @@
       "hooks": [
         {
           "type": "command",
-          "command": "bun bin/failproofai.mjs --hook PreCompact --cli factory",
+          "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PreCompact --cli factory",
           "timeout": 30,
           "__failproofai_hook__": true
         }
@@ -102,7 +102,7 @@
       "hooks": [
         {
           "type": "command",
-          "command": "bun bin/failproofai.mjs --hook SessionEnd --cli factory",
+          "command": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook SessionEnd --cli factory",
           "timeout": 30,
           "__failproofai_hook__": true
         }
diff --git a/.github/hooks/failproofai.json b/.github/hooks/failproofai.json
index 918927d5..0622d16a 100644
--- a/.github/hooks/failproofai.json
+++ b/.github/hooks/failproofai.json
@@ -6,8 +6,8 @@
         "hooks": [
           {
             "type": "command",
-            "bash": "bun bin/failproofai.mjs --hook SessionStart --cli copilot",
-            "powershell": "bun bin/failproofai.mjs --hook SessionStart --cli copilot",
+            "bash": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook SessionStart --cli copilot",
+            "powershell": "if (-not (Get-Command node -ErrorAction SilentlyContinue)) { [Console]::Error.WriteLine('[failproofai] node not found; install Node >=20.9'); exit 2 }; node scripts/dev-hook.mjs --hook SessionStart --cli copilot",
             "timeoutSec": 60,
             "__failproofai_hook__": true
           }
@@ -19,8 +19,8 @@
         "hooks": [
           {
             "type": "command",
-            "bash": "bun bin/failproofai.mjs --hook SessionEnd --cli copilot",
-            "powershell": "bun bin/failproofai.mjs --hook SessionEnd --cli copilot",
+            "bash": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook SessionEnd --cli copilot",
+            "powershell": "if (-not (Get-Command node -ErrorAction SilentlyContinue)) { [Console]::Error.WriteLine('[failproofai] node not found; install Node >=20.9'); exit 2 }; node scripts/dev-hook.mjs --hook SessionEnd --cli copilot",
             "timeoutSec": 60,
             "__failproofai_hook__": true
           }
@@ -32,8 +32,8 @@
         "hooks": [
           {
             "type": "command",
-            "bash": "bun bin/failproofai.mjs --hook UserPromptSubmit --cli copilot",
-            "powershell": "bun bin/failproofai.mjs --hook UserPromptSubmit --cli copilot",
+            "bash": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook UserPromptSubmit --cli copilot",
+            "powershell": "if (-not (Get-Command node -ErrorAction SilentlyContinue)) { [Console]::Error.WriteLine('[failproofai] node not found; install Node >=20.9'); exit 2 }; node scripts/dev-hook.mjs --hook UserPromptSubmit --cli copilot",
             "timeoutSec": 60,
             "__failproofai_hook__": true
           }
@@ -45,8 +45,8 @@
         "hooks": [
           {
             "type": "command",
-            "bash": "bun bin/failproofai.mjs --hook PreToolUse --cli copilot",
-            "powershell": "bun bin/failproofai.mjs --hook PreToolUse --cli copilot",
+            "bash": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PreToolUse --cli copilot",
+            "powershell": "if (-not (Get-Command node -ErrorAction SilentlyContinue)) { [Console]::Error.WriteLine('[failproofai] node not found; install Node >=20.9'); exit 2 }; node scripts/dev-hook.mjs --hook PreToolUse --cli copilot",
             "timeoutSec": 60,
             "__failproofai_hook__": true
           }
@@ -58,8 +58,8 @@
         "hooks": [
           {
             "type": "command",
-            "bash": "bun bin/failproofai.mjs --hook PostToolUse --cli copilot",
-            "powershell": "bun bin/failproofai.mjs --hook PostToolUse --cli copilot",
+            "bash": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node scripts/dev-hook.mjs --hook PostToolUse --cli copilot",
+            "powershell": "if (-not (Get-Command node -ErrorAction SilentlyContinue)) { [Console]::Error.WriteLine('[failproofai] node not found; install Node >=20.9'); exit 2 }; node scripts/dev-hook.mjs --hook PostToolUse --cli copilot",
             "timeoutSec": 60,
             "__failproofai_hook__": true
           }
@@ -71,8 +71,8 @@
         "hooks": [
           {
             "type": "command",
-            "bash": "bun bin/failproofai.mjs --hook Stop --cli copilot",
-            "powershell": "bun bin/failproofai.mjs --hook Stop --cli copilot",
+            "bash": "command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 1; }; node scripts/dev-hook.mjs --hook Stop --cli copilot",
+            "powershell": "if (-not (Get-Command node -ErrorAction SilentlyContinue)) { [Console]::Error.WriteLine('[failproofai] node not found; install Node >=20.9'); exit 1 }; node scripts/dev-hook.mjs --hook Stop --cli copilot",
             "timeoutSec": 60,
             "__failproofai_hook__": true
           }
diff --git a/.opencode/plugins/failproofai.mjs b/.opencode/plugins/failproofai.mjs
index 784ab192..71f663ce 100644
--- a/.opencode/plugins/failproofai.mjs
+++ b/.opencode/plugins/failproofai.mjs
@@ -1,11 +1,13 @@
 // AUTO-GENERATED by failproofai. __failproofai_hook__
 // Re-generate via: failproofai policies --install --cli opencode
 //
-// DEV variant: this repo's contributors run failproofai from source via
-// `bun bin/failproofai.mjs ...` instead of `npx -y failproofai`. This file
-// is the project-scope shim with that dev path baked in. The production
-// shape (npx-based) is generated by `src/hooks/integrations.ts` on install
-// for end users — see `buildOpenCodePluginShim` there.
+// DEV variant: this repo's contributors run failproofai from source, via
+// the shared `scripts/dev-hook.mjs` resolver rather than `npx -y failproofai`.
+// That resolver locates bun across PATH, $BUN_INSTALL/bin, ~/.bun/bin, Homebrew
+// and every nvm version dir — a bare `spawnSync("bun")` silently fails open the
+// moment bun is off the hook's PATH. The production shape (npx-based) is
+// generated by `src/hooks/integrations.ts` on install for end users — see
+// `buildOpenCodePluginShim` there.
 //
 // Do NOT install this repo via `failproofai policies --install --cli
 // opencode --scope project` — it would overwrite this dev path with the
@@ -17,10 +19,7 @@
 // When #337 landed, this dev shim drifted and `block-read-outside-cwd`
 // silently no-op'd on every opencode `read` call inside this repo.
 import { spawnSync } from "node:child_process";
-import { resolve } from "node:path";
-
-const REPO_ROOT = resolve(import.meta.dirname, "..", "..");
-const FAILPROOFAI_DEV_BIN = resolve(REPO_ROOT, "bin", "failproofai.mjs");
+import { resolveDevSpawn } from "../../scripts/dev-hook.mjs";
 
 const BUS_EVENT_MAP = {
   "session.created": "SessionStart",
@@ -72,13 +71,33 @@ function canonicalizeToolInput(canonicalToolName, args) {
 }
 
 function runFailproofai(eventName, payload, directory) {
-  const r = spawnSync("bun", [FAILPROOFAI_DEV_BIN, "--hook", eventName, "--cli", "opencode"], {
+  // Shared with the JSON configs' launcher: locates bun across PATH, ~/.bun/bin,
+  // $BUN_INSTALL, Homebrew and every nvm version dir. A bare spawnSync("bun")
+  // dies with ENOENT the moment bun is off the hook's PATH.
+  const spawn = resolveDevSpawn();
+  if (!spawn) {
+    process.stderr.write(
+      "[failproofai-dev] bun not found — opencode policies are NOT enforcing. " +
+        "Install bun: curl -fsSL https://bun.sh/install | bash\n",
+    );
+    return { exitCode: 0, stdout: "", stderr: "" };
+  }
+  const r = spawnSync(spawn.cmd, [...spawn.args, "--hook", eventName, "--cli", "opencode"], {
     input: JSON.stringify(payload),
     encoding: "utf8",
     timeout: 60_000,
     cwd: directory,
   });
-  return { exitCode: r.status ?? 0, stdout: r.stdout ?? "", stderr: r.stderr ?? "" };
+  // `r.status` is null when the spawn never ran (ENOENT) or the child was
+  // killed. Coercing that to 0 reports "allowed" for a policy that never got
+  // to run, so say so on stderr rather than failing open in silence.
+  if (r.status === null) {
+    process.stderr.write(
+      `[failproofai-dev] ${eventName} hook did not run (${r.error?.code ?? r.signal ?? "unknown"}) — not enforcing\n`,
+    );
+    return { exitCode: 0, stdout: "", stderr: "" };
+  }
+  return { exitCode: r.status, stdout: r.stdout ?? "", stderr: r.stderr ?? "" };
 }
 
 async function applyDecision(result, ctx, eventName) {
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 168aef80..936bd614 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@
 - Redirect the 13 AgentEye pages the upstream syncs deleted (`/agenteye/deployment`, `/agenteye/kubernetes-deployment`, `/agenteye/troubleshooting`, …) to a live page instead of hard-404ing. (#556)
 
 ### Fixes
+- Stop this repo's dogfood hooks from silently no-op'ing when `bun` isn't on the hook's PATH. All 75 hook commands across the 8 project-level agent-CLI configs fired `bun bin/failproofai.mjs --hook <Event>` directly, so whenever the agent CLI was handed a PATH without bun — `npm i -g bun` installs into a single nvm version's bin dir, so `nvm use <other>` drops it; a macOS GUI launch inherits a launchd PATH built without `~/.zshrc` — every event died with exit 127 and the session ran with **zero** policy enforcement, saying nothing. The configs now call a dev-only `node scripts/dev-hook.mjs` launcher that locates bun across `PATH`, `$BUN_INSTALL/bin`, `~/.bun/bin`, the node execPath sibling, Homebrew/`/usr/local`, and every `~/.nvm/versions/node/*/bin`; installs it via npm if it is genuinely absent; builds `dist/index.js` when missing so `.failproofai/policies/*.mjs` can resolve `import ... from 'failproofai'`; then re-execs the real binary with `stdio: "inherit"` (byte-exact stdout — the deny contracts are JSON on stdout) and propagates the exit code verbatim (2 still means deny; signals map to 128+signum as `sh` did). A `command -v node` pre-check fronts each command so a missing node is a loud one-liner rather than silence — exit 2 on tool events, exit 1 on stop-class events, where exit 2 would mean "retry" and loop forever. The `.opencode` dev shim shares the same resolver and no longer reports a never-run hook as `exitCode: 0` (a silent allow). Production users on `npx -y failproofai` are unaffected. A new drift-guard test reads every committed dogfood config and asserts the launcher form, guard, exit-code split, and per-file command counts — these configs are generated by nothing and read by nothing, which is how #337's opencode shim drifted and silently no-op'd `block-read-outside-cwd` repo-wide. (#564)
 - Delete translated pages whose English source no longer exists, and stop them coming back: `translate-docs` gained a `--prune` mode that runs by default on every translation pass (`--no-prune` opts out) and as an explicit step in the `consolidate` job — that job re-checks-out `main` and *overlays* the artifacts, so a prune done only in the per-language jobs would be undone. Translation only ever moved forward, so the 11 pages the AgentEye syncs removed upstream left 154 orphans (11 × 14 locales) that `--update-nav` dropped from the sidebar but Mintlify still served and indexed — non-English readers could land on docs for a deleted feature with no way out. A repo invariant test now fails if any translation outlives its English source. (#556)
 - Move the docs auto-translation daily cron from 06:00 UTC to 11:05 AM IST (05:35 UTC, encoded as `35 5 * * *` since GitHub Actions cron is always UTC). (#553)
 
diff --git a/CLAUDE.md b/CLAUDE.md
index ec5d2914..2e84b5f1 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -10,14 +10,44 @@
 
 ## Dev hooks (this repo only)
 
-This repo's `.claude/settings.json` uses `bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook <EventType>`
-instead of the standard `npx -y failproofai` command. This is because `npx -y failproofai`
+Every dogfood config in this repo routes through **`scripts/dev-hook.mjs`**, a dev-only
+launcher, instead of the standard `npx -y failproofai` command — `npx -y failproofai`
 creates a self-referencing conflict when run inside the failproofai project itself.
+`.claude/settings.json` uses:
 
-The path **must** start with `$CLAUDE_PROJECT_DIR` (not a relative `./bin/...`). Claude
-Code spawns hooks with the live session CWD, which drifts whenever the agent `cd`s into a
-subdirectory — a relative path then fails with `Module not found "./bin/failproofai.mjs"`.
-`$CLAUDE_PROJECT_DIR` is set once per session to the project root and never drifts.
+```
+command -v node >/dev/null 2>&1 || { echo '[failproofai] node not found; install Node >=20.9' >&2; exit 2; }; node "$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs" --hook <EventType>
+```
+
+**Why node fronts a bun-only binary.** `bin/failproofai.mjs` cannot run under node — it
+does a bare `import { version } from "../package.json"` (node needs `with { type: "json" }`)
+and `await import("../src/hooks/handler")`, an extensionless TypeScript specifier node
+cannot resolve. But naming `bun` directly in the config makes every hook exit 127 the
+moment bun is off the *hook's* PATH — which happens routinely even when bun is on yours:
+`npm i -g bun` installs into ONE nvm version's bin dir, so `nvm use <other>` drops it; a
+macOS GUI launch gets a launchd PATH built without `~/.zshrc`. The session then runs with
+zero enforcement, silently. The launcher locates bun across PATH, `$BUN_INSTALL/bin`,
+`~/.bun/bin`, Homebrew, and every `~/.nvm/versions/node/*/bin`; installs it via npm if it
+is genuinely absent; ensures `dist/index.js` exists so `.failproofai/policies/*.mjs` can
+resolve `import ... from 'failproofai'`; then delegates with `stdio: "inherit"` and
+propagates the child's exit code verbatim.
+
+**The `command -v node` prefix is a pre-check, never a `||` fallback.** Exit 2 is the deny
+signal, so a reactive `launcher || fallback` chain would re-fire on every legitimate
+denial. Stop-class events (`Stop`, `StopFailure`, `SubagentStop`) use `exit 1` instead of
+`exit 2` — exit 2 there means "don't finish, retry", and a shell guard can't read
+`stop_hook_active` off stdin to know it is already retrying, so it would loop forever.
+
+The `.claude` path **must** start with `$CLAUDE_PROJECT_DIR` (not a relative `./scripts/...`).
+Claude Code spawns hooks with the live session CWD, which drifts whenever the agent `cd`s
+into a subdirectory — a relative path then fails with `Cannot find module`.
+`$CLAUDE_PROJECT_DIR` is set once per session to the project root and never drifts. (The
+other CLIs use a relative path; they spawn hooks from the project root.)
+
+`__tests__/hooks/dogfood-configs.test.ts` is the tripwire for all of the above — it reads
+every committed dogfood config and asserts the launcher form, the guard, the exit-code
+split, and the per-file command counts. These configs are hand-maintained and generated by
+nothing, so without it they drift silently (see #337).
 
 For all other repos, the recommended approach is `npx -y failproofai`, installed via:
 ```bash
@@ -33,7 +63,7 @@ This repo also ships a `.codex/hooks.json` for OpenAI Codex sessions, mirroring
 `.claude/settings.json` setup. Codex does **not** define an equivalent of
 `$CLAUDE_PROJECT_DIR` — its stdin payload exposes `cwd` but the hook command string
 runs before stdin is read. Codex hook commands are spawned with the project root as
-cwd (where `codex` was launched), so we use a relative `bun bin/failproofai.mjs`
+cwd (where `codex` was launched), so we use a relative `node scripts/dev-hook.mjs`
 path. If Codex ever changes that behavior and the hook fails to find the binary,
 switch to an absolute path.
 
@@ -57,7 +87,7 @@ milliseconds, for its timeout field).
 
 Like Codex, Copilot does not expose a `$COPILOT_PROJECT_DIR` env var, and its
 hooks are spawned with the project root as cwd, so we use a relative
-`bun bin/failproofai.mjs --hook ... --cli copilot` path. If Copilot ever
+`node scripts/dev-hook.mjs --hook ... --cli copilot` path. If Copilot ever
 changes that behavior and the hook fails to find the binary, switch to an
 absolute path.
 
@@ -131,7 +161,7 @@ existing builtin policies fire unchanged.
 Like Codex and Copilot, Cursor does not expose a `$CURSOR_PROJECT_DIR` env
 var to the hook command line (only as a process env var inside the hook
 itself), and Cursor hooks are spawned with the project root as cwd, so we
-use a relative `bun bin/failproofai.mjs --hook ... --cli cursor` path. If
+use a relative `node scripts/dev-hook.mjs --hook ... --cli cursor` path. If
 Cursor ever changes that behavior and the hook fails to find the binary,
 switch to an absolute path.
 
@@ -179,7 +209,7 @@ and a matching entry in `.opencode/opencode.json`'s `plugin: []` array.
 OpenCode's extensibility model is fundamentally different from Claude /
 Codex / Copilot / Cursor: it has **no external-command hook system**.
 Plugins are in-process JS/TS modules loaded by opencode at startup. The
-shim subprocess-calls the failproofai binary (`bun bin/failproofai.mjs
+shim subprocess-calls the failproofai binary (`node scripts/dev-hook.mjs
 --hook ... --cli opencode` for dev) and translates the binary's existing
 Claude-shape JSON response back into plugin semantics — `throw new
 Error(reason)` for deny, `client.session.prompt(...)` for instruct,
@@ -199,7 +229,7 @@ failproofai policies --install --cli opencode --scope project
 which writes a portable `npx -y failproofai --hook ... --cli opencode`
 command into the shim. Same self-reference caveat applies — do **not**
 install the standard `npx` form from inside this repo (it would overwrite
-the dev `bun bin/failproofai.mjs` path).
+the dev `node scripts/dev-hook.mjs` path).
 
 ### Pi hooks (`.pi/settings.json`)
 
@@ -449,7 +479,7 @@ failproofai policies --install --cli openclaw --scope user
 Factory's **droid** CLI is a **dual-pillar** integration (live hooks + audit),
 supporting **user + project** scope. Unlike Hermes/OpenClaw it uses a
 Claude/Codex-style **external shell-hook system** — the installed command is
-`bun bin/failproofai.mjs --hook <event> --cli factory` (dev) /
+`node scripts/dev-hook.mjs --hook <event> --cli factory` (dev) /
 `npx -y failproofai --hook <event> --cli factory` (production project scope).
 The entire contract below was **verified live against droid v0.171.0**.
 
@@ -694,7 +724,7 @@ events; Goose **auto-discovers** any dir under `~/.agents/plugins/<name>/` (user
 or `<cwd>/.agents/plugins/<name>/` (project) at startup and **self-registers** it
 into `~/.config/goose/config.yaml`. So the installer just **drops the plugin dir**
 (no config edit — simpler than OpenCode). The installed command is
-`bun bin/failproofai.mjs --hook <event> --cli goose` (dev) /
+`node scripts/dev-hook.mjs --hook <event> --cli goose` (dev) /
 `npx -y failproofai --hook <event> --cli goose` (production).
 
 **Schema: an Open Plugins `hooks.json` WITH a top-level `"hooks"` wrapper** (unlike
@@ -762,7 +792,7 @@ failproofai policies --install --cli goose --scope project
 Like the Codex / Cursor / OpenCode / Pi setups above, this repo ships
 **project-scope dogfood configs** for the four newest CLIs so failproofai
 enforces on itself when you drive this repo with them. Each uses the dev
-`bun bin/failproofai.mjs --hook <event> --cli <cli>` command (never the `npx`
+`node scripts/dev-hook.mjs --hook <event> --cli <cli>` command (never the `npx`
 production form — same self-reference caveat as the others):
 
 | CLI | Dogfood path | Schema |
@@ -776,7 +806,7 @@ These were generated from each integration's own `writeHookEntries`, so they
 track the live schema. See each CLI's architecture section above for the full
 contract. As with the other CLIs, do **not** run
 `failproofai policies --install --cli <cli>` from inside this repo — it would
-overwrite the dev `bun bin/failproofai.mjs` path with the production `npx` form.
+overwrite the dev `node scripts/dev-hook.mjs` path with the production `npx` form.
 
 ## Workflow rules
 
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 8da1b944..217bc474 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -4,7 +4,10 @@ Thanks for your interest in contributing! Here's how to get started.
 
 ## Prerequisites
 
-- Bun >= 1.3.0 (or Node.js >= 20.9.0)
+- Bun >= 1.3.0 — required, not optional. `bun install` runs `prepare` → `bun run build`,
+  which shells out to `bun build`, so there is no Node-only setup path.
+- Node.js >= 20.9.0 — what the published package targets, and what runs the in-repo
+  dev hooks' launcher.
 
 ## Development Setup
 
@@ -20,12 +23,19 @@ The dev server starts at `http://localhost:8020`.
 ### Build before the in-repo dev hooks will work
 
 This repo **dogfoods failproofai on itself**: `.claude/settings.json` (and the
-sibling `.codex/`, `.cursor/`, `.github/hooks/`, … configs) register
-hooks that run `bun bin/failproofai.mjs --hook <Event>`. Those hooks load the
-custom policies in `.failproofai/policies/*.mjs`, which `import` the
-`failproofai` package — resolved against the **compiled `dist/index.js` bundle**.
-
-If `dist/` is missing or stale you'll see hook errors like:
+sibling `.codex/`, `.cursor/`, `.github/hooks/`, … configs) register hooks that run
+`node scripts/dev-hook.mjs --hook <Event> --cli <cli>`. That launcher locates `bun`
+(across `PATH`, `$BUN_INSTALL/bin`, `~/.bun/bin`, Homebrew, and every
+`~/.nvm/versions/node/*/bin`), builds `dist/index.js` if it is missing, then hands off
+to `bin/failproofai.mjs`. See `scripts/dev-hook.mjs` for why node fronts a bun-only
+binary. Those hooks load the custom policies in `.failproofai/policies/*.mjs`, which
+`import` the `failproofai` package — resolved against the **compiled `dist/index.js`
+bundle**.
+
+If `dist/` is missing the launcher rebuilds it for you and says so on stderr. If it is
+**stale** — you changed `src/index.ts` and the bundle predates it — nothing detects that,
+and you'll get policies enforcing yesterday's code. When the bundle is missing *and* the
+launcher can't run, the errors look like:
 
 ```
 [failproofai:hook] ERROR failed to load custom hooks from
@@ -33,8 +43,8 @@ If `dist/` is missing or stale you'll see hook errors like:
 ```
 
 `bun install` builds `dist/` for you via its `prepare` script, so a clean clone
-just works. **Build explicitly whenever the bundle is missing or you've changed
-`src/`** (the hooks run the compiled bundle, not your live `src/`):
+just works. **Rebuild explicitly whenever you've changed `src/`** (the hooks load the
+compiled bundle, not your live `src/`):
 
 ```bash
 bun run build   # full build (Next.js + dist/)
diff --git a/__tests__/hooks/dogfood-configs.test.ts b/__tests__/hooks/dogfood-configs.test.ts
new file mode 100644
index 00000000..39a344e8
--- /dev/null
+++ b/__tests__/hooks/dogfood-configs.test.ts
@@ -0,0 +1,186 @@
+// @vitest-environment node
+/**
+ * Drift guard for THIS repo's dogfood hook configs.
+ *
+ * These configs are hand-maintained, are not generated by `integrations.ts`,
+ * and nothing else in the suite reads them — so when one drifts, it drifts
+ * silently and the repo simply stops enforcing its own policies. That is not
+ * hypothetical: when #337 landed, the opencode dev shim drifted and
+ * `block-read-outside-cwd` no-op'd on every opencode read in this repo,
+ * unnoticed. This file is the tripwire.
+ *
+ * It asserts the *dev* form. The production `npx -y failproofai` form that
+ * users install is covered separately by __tests__/hooks/integrations.test.ts.
+ */
+import { describe, it, expect } from "vitest";
+import { existsSync, readFileSync } from "node:fs";
+import { resolve } from "node:path";
+
+const ROOT = process.cwd();
+const LAUNCHER = "scripts/dev-hook.mjs";
+
+/** Keys that hold a shell command. `bash`/`powershell` are Copilot's schema. */
+const COMMAND_KEYS = new Set(["command", "bash", "powershell"]);
+
+/**
+ * The five dogfood schemas differ wildly (Claude-nested, Cursor-flat, Factory
+ * top-level-keys, Antigravity named-hook, Copilot bash+powershell). Rather than
+ * encode all five, walk the tree and pick up anything that looks like one of
+ * our commands — new schemas come along for free.
+ */
+function collectHookCommands(node: unknown, out: string[] = []): string[] {
+  if (Array.isArray(node)) {
+    for (const v of node) collectHookCommands(v, out);
+    return out;
+  }
+  if (node && typeof node === "object") {
+    for (const [k, v] of Object.entries(node)) {
+      if (typeof v === "string" && COMMAND_KEYS.has(k) && v.includes("failproofai")) out.push(v);
+      else collectHookCommands(v, out);
+    }
+  }
+  return out;
+}
+
+function commandsIn(file: string): string[] {
+  return collectHookCommands(JSON.parse(readFileSync(resolve(ROOT, file), "utf8")));
+}
+
+/**
+ * Events where exit 2 means "don't finish, retry". A shell guard can't read
+ * `stop_hook_active` off stdin to know it's already retrying, so it must not
+ * deny here — it would loop forever. Everything else gets exit 2, which
+ * genuinely blocks on Claude/Factory/Goose and surfaces loudly elsewhere.
+ */
+const STOP_CLASS = new Set(["Stop", "StopFailure", "SubagentStop", "stop", "subagentStop"]);
+
+const CONFIGS = [
+  { file: ".claude/settings.json", cli: null, count: 26 },
+  { file: ".codex/hooks.json", cli: "codex", count: 6 },
+  { file: ".github/hooks/failproofai.json", cli: "copilot", count: 12 }, // 6 events × bash+powershell
+  { file: ".cursor/hooks.json", cli: "cursor", count: 6 },
+  { file: ".factory/hooks.json", cli: "factory", count: 9 },
+  { file: ".devin/config.json", cli: "devin", count: 7 },
+  { file: ".agents/hooks.json", cli: "antigravity", count: 4 },
+  { file: ".agents/plugins/failproofai/hooks/hooks.json", cli: "goose", count: 5 },
+];
+
+describe.each(CONFIGS)("$file", ({ file, cli, count }) => {
+  it(`registers exactly ${count} failproofai commands`, () => {
+    // Catches an event silently dropped during a hand-edit.
+    expect(commandsIn(file)).toHaveLength(count);
+  });
+
+  it("routes every command through the dev launcher", () => {
+    // .claude quotes the path so a $CLAUDE_PROJECT_DIR containing spaces still
+    // resolves; the others pass it bare.
+    for (const cmd of commandsIn(file)) expect(cmd).toMatch(/scripts\/dev-hook\.mjs"? --hook /);
+  });
+
+  it("never spawns bun directly", () => {
+    // The whole point: `bun ...` dies with exit 127 when bun is off the hook's
+    // PATH, and the session runs unenforced without saying so.
+    for (const cmd of commandsIn(file)) expect(cmd).not.toMatch(/(^|[|;&\s])bun\s/);
+  });
+
+  it("never uses the production npx form", () => {
+    // `failproofai policies --install --scope project` run inside this repo
+    // would rewrite these to npx, which enforces the *published* package
+    // against the working tree. That is the #337 class of silent wrongness.
+    for (const cmd of commandsIn(file)) expect(cmd).not.toContain("npx -y failproofai");
+  });
+
+  it("guards on node before invoking the launcher, never after", () => {
+    // A reactive `launcher || fallback` chain would re-fire the fallback on
+    // every legitimate exit-2 denial. The check must precede the launcher.
+    for (const cmd of commandsIn(file)) {
+      expect(cmd).toMatch(/^(command -v node|if \(-not \(Get-Command node)/);
+      expect(cmd).not.toMatch(/dev-hook\.mjs[^;]*\|\|/);
+    }
+  });
+
+  it("exits 1 on stop-class events and 2 everywhere else", () => {
+    for (const cmd of commandsIn(file)) {
+      const event = /--hook (\S+)/.exec(cmd)?.[1];
+      expect(event).toBeDefined();
+      const expected = STOP_CLASS.has(event!) ? 1 : 2;
+      expect(`${event} → exit ${/exit (\d)/.exec(cmd)?.[1]}`).toBe(`${event} → exit ${expected}`);
+    }
+  });
+
+  if (cli) {
+    it(`passes --cli ${cli}`, () => {
+      for (const cmd of commandsIn(file)) expect(cmd).toContain(`--cli ${cli}`);
+    });
+  } else {
+    it("omits --cli, relying on the cli=claude default", () => {
+      for (const cmd of commandsIn(file)) expect(cmd).not.toContain("--cli ");
+    });
+  }
+});
+
+describe("copilot's dual-shell schema", () => {
+  const file = ".github/hooks/failproofai.json";
+
+  it("uses the POSIX guard on bash and the PowerShell guard on powershell", () => {
+    const cfg = JSON.parse(readFileSync(resolve(ROOT, file), "utf8"));
+    const entries: { bash?: string; powershell?: string }[] = [];
+    const walk = (n: unknown): void => {
+      if (Array.isArray(n)) return n.forEach(walk);
+      if (n && typeof n === "object") {
+        const o = n as Record<string, unknown>;
+        if (typeof o.bash === "string" && typeof o.powershell === "string") {
+          entries.push(o as { bash: string; powershell: string });
+        }
+        Object.values(o).forEach(walk);
+      }
+    };
+    walk(cfg);
+
+    expect(entries).toHaveLength(6);
+    for (const e of entries) {
+      expect(e.bash).toMatch(/^command -v node/);
+      expect(e.powershell).toMatch(/^if \(-not \(Get-Command node/);
+      // `command -v` is not a PowerShell builtin; shipping it there would make
+      // the guard itself the thing that fails.
+      expect(e.powershell).not.toContain("command -v");
+    }
+  });
+});
+
+describe("the surfaces that spawn bun from JS rather than a config", () => {
+  it("the opencode dev shim resolves bun via the shared resolver", () => {
+    const src = readFileSync(resolve(ROOT, ".opencode/plugins/failproofai.mjs"), "utf8");
+    expect(src).toContain("resolveDevSpawn");
+    // Strip comments — prose is free to mention the anti-pattern it warns about.
+    const code = src.replace(/\/\*[\s\S]*?\*\//g, "").replace(/^\s*\/\/.*$/gm, "");
+    expect(code).not.toMatch(/spawnSync\(\s*"bun"/);
+  });
+
+  /**
+   * Known gap, encoded deliberately. `.pi/settings.json` loads
+   * `pi-extension/index.ts`, whose resolveSpawn() has the same bare-"bun"
+   * fallback — but that file ships to users in the npm tarball, where
+   * dist-first is the correct order. Fixing it means changing shipped
+   * behaviour, so it is out of scope here. This test documents the hole so
+   * nobody mistakes it for coverage.
+   */
+  it("pi's dogfood surface is knowingly NOT protected", () => {
+    const src = readFileSync(resolve(ROOT, "pi-extension/index.ts"), "utf8");
+    expect(src).toContain('cmd: "bun"');
+  });
+});
+
+describe("repo-wide invariants", () => {
+  it("the launcher every config points at exists", () => {
+    expect(existsSync(resolve(ROOT, LAUNCHER))).toBe(true);
+  });
+
+  it("the hook-sync image still installs bun", () => {
+    // The launcher only *finds* bun; it cannot conjure it. That container runs
+    // headless with no bun of its own, so without this layer the
+    // require-*-before-stop policies driving its auto-PR never fire.
+    const dockerfile = readFileSync(resolve(ROOT, "docker-hook-sync/Dockerfile"), "utf8");
+    expect(dockerfile).toMatch(/bun/i);
+  });
+});
diff --git a/__tests__/scripts/dev-hook-resolver.test.ts b/__tests__/scripts/dev-hook-resolver.test.ts
new file mode 100644
index 00000000..cbab9e29
--- /dev/null
+++ b/__tests__/scripts/dev-hook-resolver.test.ts
@@ -0,0 +1,234 @@
+// @vitest-environment node
+import { describe, it, expect, vi } from "vitest";
+import { readFileSync } from "node:fs";
+import { resolve } from "node:path";
+
+// The launcher must never shell out to find bun — it runs on every hook event,
+// so resolution is an existsSync walk. Mocking child_process lets the "never
+// spawns" test below prove that rather than assume it.
+const spawnSync = vi.fn();
+vi.mock("node:child_process", () => ({ spawnSync }));
+
+const LAUNCHER = "../../scripts/dev-hook.mjs";
+const HOME = "/fake/home";
+
+/** Every dep injected, so no test touches the real filesystem or env. */
+function deps(overrides: Record<string, unknown> = {}) {
+  return {
+    env: {},
+    platform: "linux",
+    execPath: "/usr/bin/node",
+    home: HOME,
+    exists: () => false,
+    readdir: () => [],
+    ...overrides,
+  };
+}
+
+/** exists() backed by an explicit set — anything else does not exist. */
+function existsIn(...paths: string[]) {
+  const set = new Set(paths);
+  return (p: string) => set.has(p);
+}
+
+describe("findBun — locating the bun executable", () => {
+  it("returns the first PATH entry that has bun", async () => {
+    const { findBun } = await import(LAUNCHER);
+    expect(
+      findBun(deps({ env: { PATH: "/a:/b" }, exists: existsIn("/a/bun", "/b/bun") })),
+    ).toBe("/a/bun");
+  });
+
+  it("skips PATH entries that do not have bun", async () => {
+    const { findBun } = await import(LAUNCHER);
+    expect(
+      findBun(deps({ env: { PATH: "/empty:/also-empty:/b" }, exists: existsIn("/b/bun") })),
+    ).toBe("/b/bun");
+  });
+
+  it("ignores empty PATH segments", async () => {
+    const { findBun } = await import(LAUNCHER);
+    expect(
+      findBun(deps({ env: { PATH: "::/b:" }, exists: existsIn("/b/bun") })),
+    ).toBe("/b/bun");
+  });
+
+  it("falls back to $BUN_INSTALL/bin when PATH has no bun", async () => {
+    const { findBun } = await import(LAUNCHER);
+    expect(
+      findBun(deps({
+        env: { PATH: "/nope", BUN_INSTALL: "/opt/bun" },
+        exists: existsIn("/opt/bun/bin/bun"),
+      })),
+    ).toBe("/opt/bun/bin/bun");
+  });
+
+  // The macOS GUI-launch case: launchd builds PATH without ~/.zshrc, so
+  // ~/.bun/bin is absent from the hook's PATH while bun is right there on disk.
+  it("falls back to ~/.bun/bin — the macOS GUI-launch case", async () => {
+    const { findBun } = await import(LAUNCHER);
+    expect(
+      findBun(deps({ env: { PATH: "/usr/bin" }, exists: existsIn(`${HOME}/.bun/bin/bun`) })),
+    ).toBe(`${HOME}/.bun/bin/bun`);
+  });
+
+  it("falls back to Homebrew before /usr/local", async () => {
+    const { findBun } = await import(LAUNCHER);
+    expect(
+      findBun(deps({
+        env: { PATH: "/nope" },
+        exists: existsIn("/opt/homebrew/bin/bun", "/usr/local/bin/bun"),
+      })),
+    ).toBe("/opt/homebrew/bin/bun");
+  });
+
+  it("skips the POSIX prefixes on win32", async () => {
+    const { findBun } = await import(LAUNCHER);
+    expect(
+      findBun(deps({
+        platform: "win32",
+        env: { PATH: "C:\\nope" },
+        exists: existsIn("/opt/homebrew/bin/bun", "/usr/local/bin/bun"),
+      })),
+    ).toBeNull();
+  });
+
+  // The load-bearing case. `npm i -g bun` puts bun in ONE nvm version's bin,
+  // so `nvm use <other>` drops it off PATH entirely even though it still works.
+  it("finds bun in another nvm version dir when the active node's dir has none", async () => {
+    const { findBun } = await import(LAUNCHER);
+    const nvm = `${HOME}/.nvm/versions/node`;
+    expect(
+      findBun(deps({
+        env: { PATH: `${nvm}/v24.0.0/bin` },
+        execPath: `${nvm}/v24.0.0/bin/node`,
+        readdir: (p: string) => (p === nvm ? ["v20.1.0", "v24.0.0", "v26.5.0"] : []),
+        exists: existsIn(`${nvm}/v26.5.0/bin/bun`),
+      })),
+    ).toBe(`${nvm}/v26.5.0/bin/bun`);
+  });
+
+  it("prefers the newest nvm version when several have bun", async () => {
+    const { findBun } = await import(LAUNCHER);
+    const nvm = `${HOME}/.nvm/versions/node`;
+    expect(
+      findBun(deps({
+        env: { PATH: "/nope" },
+        readdir: (p: string) => (p === nvm ? ["v20.1.0", "v26.5.0"] : []),
+        exists: existsIn(`${nvm}/v20.1.0/bin/bun`, `${nvm}/v26.5.0/bin/bun`),
+      })),
+    ).toBe(`${nvm}/v26.5.0/bin/bun`);
+  });
+
+  // Only the executable *name* is platform-driven here — PATH splitting and
+  // joining come from the host's node:path, so these run with POSIX-shaped
+  // dirs even while asserting win32 naming.
+  it("prefers bun.exe over bare bun on win32", async () => {
+    const { findBun } = await import(LAUNCHER);
+    expect(
+      findBun(deps({
+        platform: "win32",
+        env: { PATH: "/tools" },
+        exists: existsIn("/tools/bun.exe", "/tools/bun"),
+      })),
+    ).toBe("/tools/bun.exe");
+  });
+
+  it("returns null when bun exists nowhere", async () => {
+    const { findBun } = await import(LAUNCHER);
+    expect(findBun(deps({ env: { PATH: "/a:/b" } }))).toBeNull();
+  });
+
+  it("does not probe the same directory twice", async () => {
+    const { findBun } = await import(LAUNCHER);
+    const seen: string[] = [];
+    findBun(deps({
+      // /usr/local/bin appears on PATH *and* as a hardcoded prefix; the node
+      // execPath sibling duplicates a PATH entry too.
+      env: { PATH: "/usr/local/bin:/usr/bin" },
+      execPath: "/usr/bin/node",
+      exists: (p: string) => {
+        seen.push(p);
+        return false;
+      },
+    }));
+    expect(seen).toStrictEqual([...new Set(seen)]);
+  });
+
+  it("never spawns a subprocess", async () => {
+    const { findBun } = await import(LAUNCHER);
+    spawnSync.mockClear();
+    findBun(deps({ env: { PATH: "/a:/b" } }));
+    expect(spawnSync).not.toHaveBeenCalled();
+  });
+});
+
+describe("findNpm", () => {
+  it("finds npm on PATH", async () => {
+    const { findNpm } = await import(LAUNCHER);
+    expect(findNpm(deps({ env: { PATH: "/usr/bin" }, exists: existsIn("/usr/bin/npm") }))).toBe(
+      "/usr/bin/npm",
+    );
+  });
+
+  it("returns null when npm is absent", async () => {
+    const { findNpm } = await import(LAUNCHER);
+    expect(findNpm(deps({ env: { PATH: "/usr/bin" } }))).toBeNull();
+  });
+
+  it("prefers npm.cmd over bare npm on win32", async () => {
+    const { findNpm } = await import(LAUNCHER);
+    expect(
+      findNpm(deps({
+        platform: "win32",
+        env: { PATH: "/tools" },
+        exists: existsIn("/tools/npm.cmd", "/tools/npm"),
+      })),
+    ).toBe("/tools/npm.cmd");
+  });
+});
+
+describe("resolveDevSpawn", () => {
+  it("pairs the resolved bun with the real binary's absolute path", async () => {
+    const { resolveDevSpawn } = await import(LAUNCHER);
+    const spawn = resolveDevSpawn(deps({ env: { PATH: "/a" }, exists: existsIn("/a/bun") }));
+    expect(spawn.cmd).toBe("/a/bun");
+    expect(spawn.args).toStrictEqual([resolve(process.cwd(), "bin", "failproofai.mjs")]);
+  });
+
+  it("returns null when bun is unfindable", async () => {
+    const { resolveDevSpawn } = await import(LAUNCHER);
+    expect(resolveDevSpawn(deps({ env: { PATH: "/a" } }))).toBeNull();
+  });
+});
+
+describe("bunMissingMessage", () => {
+  it("is a single actionable line — it can fire on all 26 events", async () => {
+    const { bunMissingMessage } = await import(LAUNCHER);
+    const msg = bunMissingMessage();
+    expect(msg).not.toContain("\n");
+    expect(msg).toContain("bun.sh/install");
+  });
+});
+
+// Every CLI except Claude and Factory reads its deny decision as JSON on the
+// hook's stdout. One stray byte from the launcher corrupts that parse and turns
+// a denial into a silent allow, so the launcher must never write there at all.
+describe("stdout purity", () => {
+  /** Launcher source with comments stripped — prose may discuss stdout freely. */
+  function launcherCode() {
+    const src = readFileSync(resolve(process.cwd(), "scripts", "dev-hook.mjs"), "utf8");
+    return src.replace(/\/\*[\s\S]*?\*\//g, "").replace(/^\s*\/\/.*$/gm, "");
+  }
+
+  it("the launcher source never writes to stdout", () => {
+    expect(launcherCode()).not.toMatch(/console\.log|process\.stdout/);
+  });
+
+  it("never hands a subprocess our stdout to write to", () => {
+    // The delegate spawn inherits all three fds on purpose — that is the whole
+    // point, the child owns the contract. Every *other* spawn (npm, bun build)
+    // must discard its stdout instead.
+    expect(launcherCode().match(/stdio:\s*"inherit"/g) ?? []).toHaveLength(1);
+  });
+});
diff --git a/docker-hook-sync/Dockerfile b/docker-hook-sync/Dockerfile
index 066d6e4e..c71d3521 100644
--- a/docker-hook-sync/Dockerfile
+++ b/docker-hook-sync/Dockerfile
@@ -5,10 +5,14 @@
 # harness we integrate with and this repo, and opens ONE auto-PR with the fix.
 #
 # Bundles:
-#   - Node 20 + npm
-#   - bun (REQUIRED: the cloned repo's .claude/settings.json fires hooks via
-#     `bun $CLAUDE_PROJECT_DIR/bin/failproofai.mjs --hook <Event>`, so the
-#     dogfooded require-*-before-stop policies enforce the commit/push/PR)
+#   - Node 20 + npm (npm is a fallback bun installer for scripts/dev-hook.mjs;
+#     node runs the launcher itself)
+#   - bun (STILL REQUIRED: the cloned repo's .claude/settings.json fires hooks via
+#     `node "$CLAUDE_PROJECT_DIR/scripts/dev-hook.mjs" --hook <Event>`, and that
+#     launcher only *locates* bun — it cannot conjure one. Without this layer the
+#     dogfooded require-*-before-stop policies never fire and the auto-PR is
+#     never committed/pushed. We install to BUN_INSTALL=/home/appuser/.bun, which
+#     the launcher probes explicitly, so enforcement survives a broken PATH.)
 #   - Claude Code CLI (`claude`) — run headless with --effort ultracode
 #   - failproofai@latest on PATH (belt-and-suspenders; the dogfood hooks actually
 #     run the clone's SOURCE via bun, not this global)
diff --git a/scripts/dev-hook.mjs b/scripts/dev-hook.mjs
new file mode 100644
index 00000000..2503d6bc
--- /dev/null
+++ b/scripts/dev-hook.mjs
@@ -0,0 +1,292 @@
+#!/usr/bin/env node
+/**
+ * failproofai DEV-ONLY hook launcher — for THIS repo's dogfood configs only.
+ *
+ * End users never run this. They install `npx -y failproofai --hook <Event>`
+ * (see `src/hooks/integrations.ts`), which resolves the published package.
+ * This file exists because this repo dogfoods itself from source, and doing so
+ * has two prerequisites that silently rot:
+ *
+ *   1. `bun` on the hook's PATH. `bin/failproofai.mjs` cannot run under node —
+ *      it does a bare `import { version } from "../package.json"` (node needs
+ *      `with { type: "json" }`) and `await import("../src/hooks/handler")`,
+ *      an extensionless TypeScript specifier node cannot resolve. But bun is
+ *      routinely absent from a hook's PATH even when it's on yours: `npm i -g
+ *      bun` installs into ONE nvm version's bin dir, so `nvm use <other>` drops
+ *      it; a macOS GUI launch gets a launchd PATH built without ~/.zshrc.
+ *      When that happens every hook exits 127 and the session runs with ZERO
+ *      policy enforcement — silently.
+ *
+ *   2. `dist/index.js`. The committed policies in `.failproofai/policies/`
+ *      `import from 'failproofai'`, which `findDistIndex()` resolves to that
+ *      bundle. Without it all three fail-open and only builtins enforce.
+ *
+ * So: locate bun (installing it via npm if we must), make sure the bundle
+ * exists, then hand off to the real binary. If we cannot enforce, say so in
+ * one line rather than failing silently.
+ *
+ * INVARIANT — never write to stdout. Most CLIs' deny contracts are JSON on
+ * stdout (Copilot `{decision:"block"}`, Cursor `{followup_message}`, Devin,
+ * Factory-on-Stop, Antigravity). A single stray byte corrupts the parse and
+ * turns a denial into an allow. Diagnostics go to stderr; subprocesses we run
+ * for our own purposes get their stdout discarded, never inherited.
+ */
+import { spawnSync } from "node:child_process";
+import { existsSync, mkdirSync, readdirSync, realpathSync, rmSync, statSync } from "node:fs";
+import { constants, homedir } from "node:os";
+import { delimiter, dirname, join, resolve } from "node:path";
+import { fileURLToPath } from "node:url";
+
+const HERE = dirname(fileURLToPath(import.meta.url));
+const REPO_ROOT = resolve(HERE, "..");
+const SRC_BIN = resolve(REPO_ROOT, "bin", "failproofai.mjs");
+const BUNDLE = resolve(REPO_ROOT, "dist", "index.js");
+const CACHE_DIR = resolve(REPO_ROOT, "node_modules", ".cache", "failproofai-dev");
+const LOCK_DIR = join(CACHE_DIR, ".lock");
+
+/** A lock older than this belonged to a process that died mid-install. */
+const LOCK_STALE_MS = 5 * 60_000;
+/** 120 × 250ms = 30s, under the tightest hook timeout (Factory/Antigravity). */
+const LOCK_WAIT_TRIES = 120;
+const LOCK_WAIT_MS = 250;
+
+/**
+ * @typedef {object} Deps
+ * @property {Record<string, string | undefined>} [env]
+ * @property {string} [platform]
+ * @property {string} [execPath]
+ * @property {string} [home]
+ * @property {(p: string) => boolean} [exists]
+ * @property {(p: string) => string[]} [readdir]
+ */
+
+function warn(msg) {
+  process.stderr.write(`[failproofai-dev] ${msg}\n`);
+}
+
+function sleepSync(ms) {
+  Atomics.wait(new Int32Array(new SharedArrayBuffer(4)), 0, 0, ms);
+}
+
+function readdirSafe(p) {
+  try {
+    return readdirSync(p);
+  } catch {
+    return [];
+  }
+}
+
+/** Executable basenames to probe, most specific first. */
+function exeNames(base, platform) {
+  return platform === "win32" ? [`${base}.exe`, `${base}.cmd`, base] : [base];
+}
+
+/** First existing `<dir>/<name>` across dirs × names, or null. */
+function probe(dirs, names, exists) {
+  for (const dir of dirs) {
+    for (const name of names) {
+      const candidate = join(dir, name);
+      if (exists(candidate)) return candidate;
+    }
+  }
+  return null;
+}
+
+/**
+ * Absolute path to a bun executable, or null. NEVER spawns a subprocess —
+ * this runs on every hook, so it is an existsSync walk and nothing more.
+ * @param {Deps} deps
+ */
+export function findBun(deps = {}) {
+  const env = deps.env ?? process.env;
+  const platform = deps.platform ?? process.platform;
+  const execPath = deps.execPath ?? process.execPath;
+  const home = deps.home ?? homedir();
+  const exists = deps.exists ?? existsSync;
+  const readdir = deps.readdir ?? readdirSafe;
+
+  const dirs = [];
+  const push = (d) => {
+    if (d && !dirs.includes(d)) dirs.push(d);
+  };
+
+  // 1. PATH — the common case, and the only one that costs nothing.
+  for (const p of (env.PATH ?? "").split(delimiter)) push(p);
+  // 2. An explicit bun install root.
+  if (env.BUN_INSTALL) push(join(env.BUN_INSTALL, "bin"));
+  // 3. Where bun.sh's installer puts it. The macOS GUI-launch case: launchd's
+  //    PATH has /usr/local/bin but never ~/.bun/bin.
+  push(join(home, ".bun", "bin"));
+  // 4. Package-manager prefixes.
+  if (platform !== "win32") {
+    push("/opt/homebrew/bin");
+    push("/usr/local/bin");
+  }
+  // 5. Every nvm-managed node version's bin dir. Load-bearing: `npm i -g bun`
+  //    lands bun in exactly ONE version's bin, so `nvm use <another>` makes it
+  //    vanish from PATH entirely while it's still perfectly usable on disk.
+  //    Descending so the newest version wins deterministically.
+  const nvmRoot = join(home, ".nvm", "versions", "node");
+  for (const v of readdir(nvmRoot).sort().reverse()) push(join(nvmRoot, v, "bin"));
+  // 6. Next to the running node. For our own `node scripts/dev-hook.mjs` form
+  //    this is a strict subset of (1) — node was resolved from PATH — so it is
+  //    a no-op. Kept only for a caller that spawns node by absolute path.
+  push(dirname(execPath));
+
+  // Cache from a previous npm-install (see installBun). Last, so a real bun
+  // that reappears on PATH always wins over our vendored copy.
+  push(join(CACHE_DIR, "node_modules", ".bin"));
+
+  return probe(dirs, exeNames("bun", platform), exists);
+}
+
+/** Absolute path to npm, or null. PATH only — npm ships beside node. */
+export function findNpm(deps = {}) {
+  const env = deps.env ?? process.env;
+  const platform = deps.platform ?? process.platform;
+  const exists = deps.exists ?? existsSync;
+  const dirs = (env.PATH ?? "").split(delimiter).filter(Boolean);
+  return probe(dirs, exeNames("npm", platform), exists);
+}
+
+/**
+ * `{ cmd, args }` to run the real binary, or null when bun is unfindable.
+ * Shared with `.opencode/plugins/failproofai.mjs`, which spawns bun itself.
+ * @param {Deps} deps
+ */
+export function resolveDevSpawn(deps = {}) {
+  const bun = findBun(deps);
+  return bun ? { cmd: bun, args: [SRC_BIN] } : null;
+}
+
+/** One actionable line. Keep it to one — this can fire on 26 events. */
+export function bunMissingMessage() {
+  return (
+    "bun not found and npm unavailable to install it — this repo's dogfood hooks are NOT " +
+    "enforcing. Install bun: curl -fsSL https://bun.sh/install | bash"
+  );
+}
+
+/**
+ * Run `doWork` at most once across concurrently-firing hooks. `mkdirSync` is
+ * atomic, so it doubles as the lock: EEXIST means another process got there.
+ * Losers wait for the artifact rather than duplicating the work.
+ */
+function ensureOnce(isDone, doWork) {
+  if (isDone()) return true;
+  mkdirSync(CACHE_DIR, { recursive: true });
+
+  for (let i = 0; i < LOCK_WAIT_TRIES; i++) {
+    if (isDone()) return true;
+    try {
+      mkdirSync(LOCK_DIR);
+    } catch (err) {
+      if (err?.code !== "EEXIST") throw err;
+      try {
+        if (Date.now() - statSync(LOCK_DIR).mtimeMs > LOCK_STALE_MS) {
+          rmSync(LOCK_DIR, { recursive: true, force: true });
+        } else {
+          sleepSync(LOCK_WAIT_MS);
+        }
+      } catch {
+        /* lock vanished under us — retry immediately */
+      }
+      continue;
+    }
+    try {
+      doWork();
+    } finally {
+      try {
+        rmSync(LOCK_DIR, { recursive: true, force: true });
+      } catch {
+        /* best effort; a leaked lock goes stale in LOCK_STALE_MS */
+      }
+    }
+    return isDone();
+  }
+  return isDone();
+}
+
+/**
+ * Vendor bun into node_modules/.cache via npm. bun ships as an npm package, so
+ * npm is the one bootstrap that works when bun is genuinely absent — building
+ * `dist/cli.mjs` to run under node can't, because `build:cli` is itself
+ * `bun build`.
+ */
+function installBun(deps = {}) {
+  const npm = findNpm(deps);
+  if (!npm) return null;
+  ensureOnce(
+    () => findBun(deps) !== null,
+    () => {
+      warn("bun not found — installing it into node_modules/.cache (one time, ~15s)");
+      const r = spawnSync(
+        npm,
+        ["install", "bun", "--prefix", CACHE_DIR, "--no-save", "--no-audit", "--no-fund", "--loglevel=error"],
+        // NOT "inherit" on stdout: npm prints there, and our stdout is a deny
+        // channel. stderr passes through so a failed install is visible.
+        { stdio: ["ignore", "ignore", "inherit"], cwd: REPO_ROOT },
+      );
+      if (r.status !== 0) warn("npm install bun failed — see the error above");
+    },
+  );
+  return findBun(deps);
+}
+
+/**
+ * Build dist/index.js if absent, so `.failproofai/policies/*.mjs` can resolve
+ * `import ... from 'failproofai'`. Non-fatal: builtins enforce without it.
+ */
+export function ensureBundle(bunPath) {
+  return ensureOnce(
+    () => existsSync(BUNDLE),
+    () => {
+      warn("dist/index.js missing — building it so .failproofai/policies/ can load (one time)");
+      const r = spawnSync(
+        bunPath,
+        ["build", "--target=node", "--format=cjs", "--outfile=dist/index.js", "src/index.ts"],
+        { stdio: ["ignore", "ignore", "inherit"], cwd: REPO_ROOT },
+      );
+      if (r.status !== 0) warn("build failed — policies in .failproofai/policies/ will NOT load");
+    },
+  );
+}
+
+function main() {
+  const bun = findBun() ?? installBun();
+  if (!bun) {
+    warn(bunMissingMessage());
+    process.exit(1);
+  }
+  ensureBundle(bun);
+
+  // stdio:"inherit" hands the child our actual fds: the payload on stdin and
+  // any decision JSON on stdout flow byte-exact, unbuffered, unparsed by us.
+  // No cwd override — the child must see whatever cwd the agent CLI chose,
+  // exactly as it did when the config spawned bun directly.
+  const r = spawnSync(bun, [SRC_BIN, ...process.argv.slice(2)], { stdio: "inherit" });
+
+  // Exit codes are a contract, not a status: 2 means DENY on Claude/Factory/
+  // Goose. Propagate verbatim. Never synthesize 2 (would deny) or 0 (would
+  // silently allow).
+  if (r.error) {
+    warn(`could not run bun (${r.error.code ?? r.error.message}) — hooks are NOT enforcing`);
+    process.exit(1);
+  }
+  if (r.status === null && r.signal) {
+    // Mirror what `sh` reports for a signalled child, which is what the agent
+    // CLI saw before this launcher sat in between.
+    process.exit(128 + (constants.signals[r.signal] ?? 15));
+  }
+  process.exit(r.status ?? 1);
+}
+
+// Only run when executed, not when `.opencode/plugins/failproofai.mjs` imports
+// the resolver. realpath so a symlinked or relative argv[1] still matches.
+let invokedDirectly = false;
+try {
+  invokedDirectly = realpathSync(fileURLToPath(import.meta.url)) === realpathSync(process.argv[1]);
+} catch {
+  invokedDirectly = false;
+}
+if (invokedDirectly) main();