> ## Documentation Index
> Fetch the complete documentation index at: https://docs.compressi.us/llms.txt
> Use this file to discover all available pages before exploring further.

# CMX Changelog: Release Notes and Version History

> What's new in each CMX release. Stable releases, bug fixes, and feature additions — with links to the full GitHub releases page for complete history.

CMX releases are published as stable builds and nightly builds. Stable builds are recommended for regular use. Every release is published with SHA256 checksums for verification.

## v0.1.38

**Stable · September 15, 2026**

This release restores effective compression for upgraded installations and repairs databases affected by incomplete historical audit migrations.

* Compression starts at 1,000 estimated tokens with a 1,000-token recent tail, five rounds, no cooldown, and a 512-token summary limit.
* Existing compression settings migrate once with an owner-only rollback copy; provider routing, protected tools, and later user changes remain intact.
* Startup repairs missing compression request identifiers without deleting usage, session, or compression history.
* Responses JSON/SSE summaries, incomplete terminal events, bounded retries, and internal usage accounting are handled consistently.
* Nudges retain the real compression result, and decision diagnostics remain content-free.
* Cache reads remain separate from estimated compressor savings and net totals.

## Full Release History

Every CMX release — including stable builds and nightlies — is listed on the [GitHub releases page](https://github.com/compressius/cmx/releases). Stable builds are also available from the [downloads page](https://compressi.us/downloads).

## Stable vs. Nightly

CMX is published to npm under two dist-tags:

* **`latest`** tracks stable releases and is what you get with a standard `npm install --global @compressius/cmx`.
* **`nightly`** tracks prerelease builds for users who want early access to new features.

Each package downloads its matching binary for your platform and verifies the SHA-256 checksum before exposing the `cmx` command. You can confirm the version you are running at any time:

```bash theme={null}
cmx --version
```

<Tip>
  Check release notes before upgrading. Run `cmx upgrade` to see if an update is available without installing it.
</Tip>


## Related topics

- [How to Update CMX to the Latest Stable or Nightly Build](/updates.md)
- [CMX CLI Reference: All Commands, Flags, and Examples](/cli-reference.md)
- [Compressius Maximus (CMX): What It Is and How It Works](/introduction.md)