diff --git a/CHANGELOG.md b/CHANGELOG.md
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+# Changelog
+
+All notable changes to `scanii-lambda` are documented here. Versions follow [SemVer](https://semver.org).
+
+## [3.0.1] — Node.js 24 handler compatibility
+
+### Fixed
+
+- `lib/s3-handler.js` and `lib/ag-handler.js` were `async` functions that still
+  accepted a `callback` parameter and called `callback(null, response)`. AWS
+  Lambda Node.js 24 removes support for callback-based handlers and rejects the
+  shape at init time with `Runtime.CallbackHandlerDeprecated`, causing the
+  v3.0.0 SAM stack to fail to start. Both handlers now use the supported
+  `async (event, context) => { return response }` pattern. See [#110](https://github.com/scanii/scanii-lambda/issues/110).
+
+### Tests / CI
+
+- Added a `handler.length <= 2` assertion to each handler's unit test suite —
+  catches any future regression to the callback shape on every PR.
+- New `Lambda Node 24 runtime init smoke` CI job spins up each handler inside
+  the official `public.ecr.aws/lambda/nodejs:24` image (Runtime Interface
+  Emulator bundled) and POSTs an invocation. Fails on any `Runtime.*` errorType
+  (`CallbackHandlerDeprecated`, `ImportModuleError`, `MalformedHandlerName`, …),
+  which catches a broader class of runtime-init regressions than `node` alone.
+- PR matrix narrowed to `ubuntu-latest` × Node 22/24. Lambda only ever runs on
+  the Linux Lambda runtime — windows/macos runners produced no useful signal.
+- Fixed a pre-existing silent test bug: `"should fail to process a directory"`
+  used a fixture key with no trailing `/`, so the guard never triggered;
+  assertions inside the (now removed) callback were silently swallowed by mocha.
+
+---
+
+## [3.0.0] — Port to `@scanii/core`, Node.js 24 runtime
+
+### Changed
+
+- Replaced the in-tree Scanii HTTP client with the published [`@scanii/core`](https://www.npmjs.com/package/@scanii/core)
+  Node SDK. The Lambda is now a thin wrapper around the canonical client; bug
+  fixes and new API surface flow in via dependency updates.
+- SAM `template.yml` runtime bumped to `nodejs24.x`.
+
+### Tests / CI
+
+- New integration tests exercise the `@scanii/core` wrapper against scanii-cli.
+- CI uses [`scanii/setup-cli-action`](https://github.com/scanii/setup-cli-action)
+  for cross-platform scanii-cli bootstrap.
+- Release workflow migrated to OIDC.
diff --git a/package.json b/package.json
index a64e24b..33729de 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "scanii-lambda",
-  "version": "3.0.0",
+  "version": "3.0.1",
   "description": "Uva Software's Scanii.com Lambda/SAM Integration",
   "main": "index.js",
   "scripts": {