diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index f1e60d5..453b9ce 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -36,7 +36,7 @@ jobs:
 
     env:
       # code0-definition release the built-in definitions are generated from.
-      DEFINITIONS_VERSION: ${{ vars.HERCULES_DEFINITIONS_VERSION || 'def-0.0.36' }}
+      DEFINITIONS_VERSION: ${{ vars.HERCULES_DEFINITIONS_VERSION || 'def-0.0.38' }}
 
     steps:
       - uses: actions/checkout@v6
diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index 29ed177..0feaf8c 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -53,7 +53,7 @@ jobs:
 
     env:
       # code0-definition release the built-in definitions are generated from.
-      DEFINITIONS_VERSION: ${{ vars.HERCULES_DEFINITIONS_VERSION || 'def-0.0.36' }}
+      DEFINITIONS_VERSION: ${{ vars.HERCULES_DEFINITIONS_VERSION || 'def-0.0.38' }}
 
     steps:
       - uses: actions/checkout@v6
diff --git a/py/README.md b/py/README.md
index b67aa05..f7cba5a 100644
--- a/py/README.md
+++ b/py/README.md
@@ -36,7 +36,7 @@ The built-in data types / functions in `hercules/definitions/` are **generated**
 release:
 
 ```bash
-uv run python scripts/build_definitions.py --version def-0.0.36
+uv run python scripts/build_definitions.py --version def-0.0.38
 ```
 
 ## Build & release
@@ -55,7 +55,7 @@ git tag 0.1.0 && git push origin 0.1.0
 ```
 
 The `code0-definition` release used for the built-in definitions is controlled by
-the `HERCULES_DEFINITIONS_VERSION` repository variable (default `def-0.0.36`).
+the `HERCULES_DEFINITIONS_VERSION` repository variable (default `def-0.0.38`).
 
 Build locally:
 
diff --git a/py/scripts/build_definitions.py b/py/scripts/build_definitions.py
index 654839e..ea22a28 100644
--- a/py/scripts/build_definitions.py
+++ b/py/scripts/build_definitions.py
@@ -9,7 +9,7 @@
 
 Usage::
 
-    python scripts/build_definitions.py --version def-0.0.36
+    python scripts/build_definitions.py --version def-0.0.38
 """
 from __future__ import annotations
 
diff --git a/ts/package.json b/ts/package.json
index 1fdadc4..c6f2f23 100644
--- a/ts/package.json
+++ b/ts/package.json
@@ -28,7 +28,7 @@
     "clean": "rm -rf dist",
     "typecheck": "tsc --noEmit",
     "test": "vitest run",
-    "build:definitions": "npx tsx scripts/build-definitions.ts -- --version def-0.0.36"
+    "build:definitions": "npx tsx scripts/build-definitions.ts -- --version def-0.0.38"
   },
   "keywords": [],
   "author": "",