fix(core): stamp libraryInfo.version with the version being released

.eslintignore

@@ -9,4 +9,5 @@ examples/
 **/*.config.js
 **/*.config.base.js
 .eslintrc.js
-constants-generator.js
+constants-generator.js
+release-stamp-version.js

devbox.lock

@@ -199,7 +199,7 @@
     },
     "nodejs@22": {
       "last_modified": "2026-03-27T11:17:38Z",
-      "plugin_version": "0.0.2",
+      "plugin_version": "0.0.4",
       "resolved": "github:NixOS/nixpkgs/832efc09b4caf6b4569fbf9dc01bec3082a00611#nodejs_22",
       "source": "devbox-search",
       "version": "22.22.2",

packages/core/constants-generator.js

@@ -1,17 +1,16 @@
 const fs = require('fs');
 const packageJson = require('./package.json');
 
+// The release passes the computed version here because package.json on master is not bumped (see release-stamp-version.js).
+const version = process.env.SEGMENT_LIBRARY_VERSION || packageJson.version;
+
 const body = `
 export const libraryInfo = {
   name: '${packageJson.name}',
-  version: '${packageJson.version}',
+  version: '${version}',
 }
 `;
 
-fs.writeFile('./src/info.ts', body, function (err) {
-  if (err) {
-    return console.log(err);
-  }
+fs.writeFileSync('./src/info.ts', body);
 
-  console.log('Configuration file has generated');
-});
+console.log(`Configuration file has generated (version ${version})`);

packages/core/release-stamp-version.js

@@ -0,0 +1,33 @@
+const { execFileSync } = require('child_process');
+const fs = require('fs');
+const path = require('path');
+
+const STAMPED_FILES = [
+  'src/info.ts',
+  'lib/commonjs/info.js',
+  'lib/module/info.js',
+];
+
+// Local semantic-release plugin: rebuilds core with the version semantic-release just computed, so the published lib/ reports it.
+async function prepare(_pluginConfig, { cwd, nextRelease, logger }) {
+  const { version } = nextRelease;
+  logger.log(`Stamping ${version} into libraryInfo and rebuilding`);
+
+  execFileSync('yarn', ['build'], {
+    cwd,
+    stdio: 'inherit',
+    env: { ...process.env, SEGMENT_LIBRARY_VERSION: version },
+  });
+
+  const quoted = new RegExp(`['"]${version.replace(/[.+]/g, '\\$&')}['"]`);
+  for (const file of STAMPED_FILES) {
+    const contents = fs.readFileSync(path.join(cwd, file), 'utf8');
+    if (!quoted.test(contents)) {
+      throw new Error(
+        `${file} is not stamped with ${version}; refusing to publish`
+      );
+    }
+  }
+}
+
+module.exports = { prepare };

packages/core/release.config.js

@@ -1,3 +1,11 @@
+const { plugins } = require('../../release.config.js');
+
 module.exports = {
   extends: ['../../release.config.js'],
+  // Runs right after @semantic-release/npm's prepare (version bump) and before its publish.
+  plugins: plugins.flatMap((plugin) =>
+    [].concat(plugin)[0] === '@semantic-release/npm'
+      ? [plugin, './release-stamp-version.js']
+      : [plugin]
+  ),
 };