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## 5.23.1

**`(fix):`** Fix `fern docs dev` hanging indefinitely on Node.js v26+ on Linux by disabling
io_uring in the child server process. Node 26 enables io_uring by default in
libuv, which has a busy-loop bug where worker threads spin on an internal
eventfd, starving the main event loop.

## 5.23.0

**`(internal):`** Add an opt-in `VerificationStep` to the post-generation pipeline that runs
`.fern/verify.sh` (when emitted by the generator) inside a language-specific
`{generatorImage}-validator` container after replay and before any GitHub
push. A failing script aborts the pipeline before opening a PR and surfaces
raw stderr through the pipeline logger; a missing script is a silent no-op.

The step is gated on a hidden `--verify` flag for `fern generate`; when
passed (with `--local` or `--runner`), the local workspace runner sets
`config.verify.enabled = true` on the pipeline and the configured container
runtime (`docker` or `podman`) is forwarded to the validator container.
Remote/Fiddle generation does not honor this flag yet.

## 5.22.1

**`(fix):`** Fix `fern docs dev` failing with pnpm 11 due to esbuild build scripts being blocked by default.
Writes `onlyBuiltDependencies` config to the bundle folder before installing esbuild.