Hygen vs Swagger Codegen

Hygen is a free, open-source code generator that runs in a project and creates code from templates. Its generators are self-contained, with folder structure defining the commands, and it looks for a local `_templates` directory so templates can stay beside project code. Built-in scaffolds help create generators, including through prompts. Templates use EJS and frontmatter, where a `to` value can set the generated file destination. Generators accept command-line arguments, interactive or multi-step prompts, file creation, and content injection into existing files. Templates can also run shell commands, while actions can select matching files with strings or regular expressions. A documented `--dry` option supports test-running generators. Hygen was built for React, Redux, and Node.js boilerplate but can be used with any technology. It runs on Linux, macOS, and Windows, is MIT licensed, and is distributed through Homebrew, npm, Yarn, npx, and standalone binaries.

Swagger Codegen is an open-source tool that generates API client libraries, server stubs and documentation from OpenAPI specifications. Its template-driven engine parses OpenAPI or Swagger definitions and produces project code from schemas. Swagger states that it can generate client SDKs in over 40 languages and server boilerplate in over 20. Listed capabilities include OpenAPI import, schema-to-code generation, project scaffolding, custom templates, an interactive API reference, code samples and a command-line interface. Outputs and integrations include HTML and Confluence Wiki documentation, Apache2 configuration files and JMeter. The project is available from GitHub under the Apache-2.0 license, with a hosted option through SwaggerHub. SwaggerHub can generate code in a selected language and push it to source-control repositories. Supported client targets include C#, Dart, Go, Java, JavaScript, Kotlin, PHP, Python, R, Ruby, Scala, Swift and TypeScript variants. Server targets include ASP.NET Core, Go, Java Vert.x and JAX-RS options. The repository warns that untrusted descriptions may cause code injection.