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OpenAPI Generator

DEVOPS
Velocity5.0

Generates API clients, server stubs and documentation from OpenAPI specs

OpenAPI Generator holds a 240-change cadence across forty-odd language targets.

code generationopenapipolyglot sdksmaven pluginspec normalisation
Current state
The project ships stable releases every four to eight weeks, each carrying 150 to 240 enhancements and fixes spread across generators for C#, Dart, Go, Java, Kotlin, C++, Crystal and dozens more. 7.25.0 follows the pattern: a parser update, restored schemaMapping imports in API interfaces, a stable input-spec hash for the Maven plugin, a way for clients to inject vendor overrides, and splitOperationsByContentType. Every recent release is labelled as carrying breaking changes with fallbacks.
Where it's heading
Two constants govern this feed. The core keeps absorbing OpenAPI 3.1 semantics - null handling, map normalisation, any-type with additional properties, allOf members alongside validation keywords - while the per-language generators take independent fixes from their own maintainers. Shipping breaking changes with fallbacks is how a project with this many downstream consumers avoids forcing coordinated upgrades, and it has held for at least six releases.
Prediction
OpenAPI 3.1 normalisation has produced fixes in every release for months and is still doing so, so expect that work to continue rather than conclude.

Recent moves

  1. 23d ago

    7.25.0: vendor override injection and 240+ fixes across generators

    A routine stable release with 240+ changes. The generally applicable items are vendor override injection for clients, splitOperationsByContentType, a stable hash for detecting spec changes in the Maven plugin, and further 3.1 normalisation; the rest is per-language maintenance.

    View source ↗
  2. 1mo ago

    7.24.0: discriminator introspection and OAS 3.1 nullable fixes

    170+ changes led by discriminator introspection for oneOf and allOf polymorphic structures, OAS 3.1 nullable normalisation, and a deep merge mode for spec merging with configurable conflict resolution.

    View source ↗
  3. 1mo ago

    7.23.0: JAX-RS security annotations and Kotlin naming break, with fallbacks

    Two named breaking changes, both with fallbacks: JAX-RS and Quarkus security annotations get emitted for empty-scope auth schemes, and Kotlin naming switches to the global prefix and suffix settings.

    View source ↗
  4. 4mo ago

    7.22.0: oneOf discriminator mapping and template manager fix

    150+ changes including a new normaliser that replaces oneOf by discriminator mapping, and a fix for a stream-closed race on concurrent JAR access in the template manager.

    View source ↗
  5. 5mo ago

    7.21.0: Spring Boot 3 becomes the default

    Spring Boot 3 becomes the default target for the Java generators - a version-default change that quietly moves what a fresh generation produces for a large share of users.

    View source ↗
  6. 7mo ago

    7.20.0: Terraform provider and C++ httplib generators

    New Terraform provider and C++ httplib generators join the roster. Target breadth is this project's core value, and each addition extends it without changing the tool's shape.

    View source ↗