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## 4.1.1

**`(fix):`** Add CLI subcommand for resolving customization conflicts on SDK generation PR branches.

## 4.1.0

**`(feat):`** Add external `$ref` bundling for AsyncAPI documents. Multi-file AsyncAPI specs
that split schemas across separate YAML files (e.g. `$ref: './schemas/types.yml#/MyType'`)
are now resolved and inlined before parsing, matching the existing behavior for OpenAPI
documents. Previously these external references caused `fern check` and `fern generate`
to fail with "Failed to resolve schema reference".

## 4.0.1

**`(fix):`** Fix `x-fern-global-headers` ignoring the `optional` field in the legacy
OpenAPI importer. Previously, all global headers were defaulted to
`optional<string>` regardless of whether `optional: false` or no `optional`
field was specified. Now headers without `optional: true` are correctly
treated as required `string` types.

## 4.0.0

**`(chore):`** Deprecate IR versions `<= 52`. Cuts down on binary size, build time, and migrations.

**Breaking changes**: To upgrade to this version of the CLI, generators now have
minimal versions they need to be upgraded to with `fern generator upgrade --include-major`:

* Python SDK: upgrade to v3.3.0-rc0+
* TypeScript SDK: upgrade to v0.38.0-rc0+
* Java SDK: upgrade to v2.5.0+
* Go SDK: upgrade to v0.28.3+
* C# SDK: upgrade to v0.5.0+
* Ruby SDK: upgrade to v1.0.0-rc1+
* Other generators: upgrade to versions that support IR v53+

## 3.98.5

**`(fix):`** Support namespace resolution in docs types. When multiple OpenAPI specs
define types with the same name (e.g., `Team` in both EntityManager and
TaskManager specs), the docs type converter now respects `x-fern-sdk-namespace`
to namespace TypeIds (e.g., `entity_manager:Team`), preventing collisions.
The namespace is resolved from `generators.yml` configuration or directly
from the `x-fern-sdk-namespace` extension in the OpenAPI/AsyncAPI spec.

## 3.98.4

**`(fix):`** Fix docs pipeline (v3-importer-commons) dropping properties from `oneOf`/`anyOf` variants
inside `allOf`. The old OpenAPI importer was fixed in 3.98.2, but the docs/register pipeline
used a separate v3-importer-commons path that still had the same bug. Properties like `content`
and `templateId` in mutual exclusion patterns (`not: {}`) are now correctly surfaced as optional
properties in generated docs.

## 3.98.3

**`(fix):`** `fern generate` now fails fast when trying to publish a version that already
exists on the target package registry (npm, PyPI, Maven Central, NuGet,
RubyGems, Go Module Proxy, crates.io). Previously, generation would run the
full pipeline before discovering the version conflict at publish time. The
check runs before IR generation for both local and remote generation, saving
significant time.

## 3.98.2

**`(fix):`** Fix OpenAPI importer dropping properties from `oneOf`/`anyOf` variants inside `allOf`.
When an `allOf` element is a bare `oneOf`/`anyOf` (commonly used for mutual exclusion
patterns like `content` vs `templateId`), the importer now extracts properties from
each variant as optional properties on the parent object. Also filters out properties
with `not: {}` schema (meaning "property must not exist").

## 3.98.1

**`(fix):`** Generate v2Examples for properties that use `$ref` or `allOf: [{ $ref }]` patterns.
Previously, when an OpenAPI property referenced another schema via `$ref` or wrapped
it in `allOf`, the property-level examples were silently dropped, resulting in empty
autogenerated examples in the IR. Now the importer runs `ExampleConverter` on these
properties to populate v2Examples correctly.