# What changed in @cloudflare/computer

> 22 changes in @cloudflare/computer 0.9 to 0.10 from its official release notes, upgrade guides and advisories: 10 breaking, 7 new APIs and options. Each one cited. Sources checked 2026-11-11. HTML: https://unstale.sh/npm/@cloudflare/computer/

To see which of these apply to a repository, run `npx @unstale/cli init` in it.

## @cloudflare/computer 0.10

### Breaking changes

- A backend without an explicit id now registers as `codemode`; saved runs under the old default id are not resumed or returned by pending or getExec. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Replaces `WorkerJavaScriptBackend` and is imported from `@cloudflare/computer/backends/codemode`. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Replaces the `WorkerJavaScriptBackendOptions` type. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Tool-set exec options now use an object containing `backends`, `output`, and `metadata`; the old backend map and `execOutput` shape is replaced. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- To disable the exec tool, configure `exec: { backends: {} }`; an empty `exec` object now throws. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- The old backend name has no alias; update imports and construction to `CodemodeBackend`. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Traces now record the backend type as `codemode`, regardless of its id. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Now requires `execution: { id, metadata }`, so code constructing host call contexts by hand must provide it. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Now requires `metadata`, so code constructing pending calls by hand must provide it. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)

### New APIs and options

- Adds values to `ctx` once per connection or run scope, and disposes them when that scope ends. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Host module calls receive the run's id and metadata in `context.execution`. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Creates the experimental `codemode:browser` host module, letting isolate JavaScript drive an agents' Browser through the same browser functions as `browserTool`. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Creates experimental host modules whose functions return objects with journaled methods and run-scoped context that can persist across pauses and restarts. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- The exec tool can set metadata for each run through its `exec` options. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Accepts string-record metadata for a run; host modules can read it through `context.execution` while the run's code cannot. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Lists run metadata with each waiting call. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)

### Behavior and default changes

- A host module call can return more than 4,096 values if the response fits the backend's byte limits. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Codemode modules can also take callbacks and return streams and live stubs in runs that do not replay. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)
- Codemode modules can take and return Date, bigint, byte and typed arrays, Headers, and errors with their names and properties. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)

### Fixes and other changes

- Stops double-encoding non-ASCII bytes written by redirected byte-oriented commands. (0.10.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.10.0)

## @cloudflare/computer 0.9

### Breaking changes

- Host and source modules for WorkerJavaScriptBackend that used the ws: prefix now use codemode: instead. (0.9.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.9.0)

### Behavior and default changes

- Custom modules now support exporting objects as well as functions. (0.9.0) — [release notes](https://github.com/cloudflare/computer/releases/tag/%40cloudflare/computer%400.9.0)