diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 4902d3c4ba..866c499f71 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -205,6 +205,15 @@ jobs:
       - run: echo "$PWD/target/debug" >> "$GITHUB_PATH" && chmod +x target/debug/mise
       - uses: ./.github/actions/mise-tools
       - run: mise x -- bun i
+      - run: mise run render
+      - name: assert render produces no diff
+        run: |
+          if [ -n "$(git status --porcelain)" ]; then
+            echo "::error::'mise run render' produced changes. Run it locally and commit."
+            git status
+            git diff HEAD
+            exit 1
+          fi
       - run: rm -rf ~/.cargo/advisory-dbs && cargo deny check
       - run: cargo msrv verify
       - run: cargo machete --with-metadata
diff --git a/xtasks/render/schema.ts b/xtasks/render/schema.ts
index 824b31e64f..0a725c0c83 100755
--- a/xtasks/render/schema.ts
+++ b/xtasks/render/schema.ts
@@ -3,6 +3,7 @@
 //MISE description="Render JSON schema"
 //MISE depends=["docs:setup"]
 
+import { spawnSync } from "node:child_process";
 import * as fs from "node:fs";
 import * as toml from "toml";
 
@@ -42,8 +43,24 @@ type NestedElement = {
   properties: Record<string, Element>;
 };
 
+const writtenPaths: string[] = [];
+
 function writeFormattedJson(path: string, value: unknown) {
   fs.writeFileSync(path, `${JSON.stringify(value, null, 2)}\n`);
+  writtenPaths.push(path);
+}
+
+function formatWithPrettier(paths: string[]) {
+  if (paths.length === 0) return;
+  const result = spawnSync("prettier", ["--write", ...paths], {
+    stdio: "inherit",
+  });
+  if (result.error) {
+    throw new Error(`prettier failed to spawn: ${result.error.message}`);
+  }
+  if (result.status !== 0) {
+    throw new Error(`prettier exited with status ${result.status}`);
+  }
 }
 
 function crawlReferencedDefs(schema: JsonObject, root: unknown) {
@@ -226,3 +243,5 @@ const misercSchema = {
 };
 
 writeFormattedJson("schema/miserc.json", misercSchema);
+
+formatWithPrettier(writtenPaths);