OpenAPI Generator — README, site & migration guide

The project’s own material, pulled in to ground openapi-generator because the X post that routed it here (T4) carries a pitch and no checkable detail. Covers the GitHub repo and README, openapi-generator.tech, and docs/migration-from-swagger-codegen.md.

What it supplies

• Repo facts: Apache-2.0, Java, ~26.5k stars / 7.6k forks, created 2018-05-12, release v7.23.0 (2026-06-08), master at 7.24.0.
• The generator catalog — the full table of API clients, server stubs, doc formats, config files, and the “Others” row (GraphQL, JMeter, Ktorm, MySQL Schema, Postman Collection, Protocol Buffer, WSDL). The site counts 50+ client and 40+ server generators.
• The fork: “OpenAPI Generator is a fork of swagger-codegen between version 2.3.1 and 2.4.0” — community-driven, positioned as a drop-in replacement, with the migration guide enumerating the renamed Docker images, Maven coordinates, generator names, and Mustache template variables.
• Run surfaces: Maven plugin, Gradle plugin, CLI via Homebrew / Docker / npm, and a hosted generator service.
• Governance: parent org OpenAPI Tools, funded via Open Collective backers and company sponsors (Datadog, Adyen, Kong, Thales among them), explicitly not affiliated with the OpenAPI Initiative.
• The security warning on untrusted specs/templates → code injection.

Tier & provenance

T1 — first-party repo and documentation. Authoritative on what the tool is, does, and came from. Self-interested on quality: the generator count is a headline number, and “50+ generators” says nothing about how good any one of them is. Star/fork counts are dated snapshots (2026-07-16); the fork story is the maintainers’ own account of a dispute they were party to.

Related

openapi-generator · openapi-generator-post · openapi-tools · schema-driven-codegen