Hygen

Hygen is a command-line code generator for building repeatable project scaffolds and editing files from templates. It is best suited to developers and teams who want generator logic versioned alongside the code it serves. Its flexible prompts and file operations make it useful for general boilerplate, but it is not designed for schema-to-code generation.

Overview

Hygen keeps generators within the project they support: self-contained generator folders map to commands, and templates can live in a local _templates directory. That arrangement makes shared scaffolding easier to maintain alongside application code, including reviewing template changes in the same pull request as code changes.

The trade-off is that Hygen does not discover templates nested down folder trees by default. That keeps startup performance in view, but teams with deeply nested template collections will need to handle that structure themselves. Hygen began as a way to reduce boilerplate in React, Redux, and Node.js work; it can be used with other technologies too.

Key features

• Generators that map to commands: Each generator is self-contained, and its folder structure determines how users invoke it. Built-in scaffolds, including a prompt-driven option, help create generators rather than requiring every one to be built from scratch.
• Template-driven file changes: EJS template bodies and frontmatter can specify destinations with a to field. Hygen can create files or inject content into existing ones; string or regular-expression subactions can select matching files within an action. This supports routine edits as well as new-file scaffolding.
• Interactive and repeatable inputs: Generators accept command-line arguments, interactive prompts, and multi-step prompt flows. That lets teams use the same generator for both scripted work and choices that depend on a developer's answers.
• Custom operations and dry runs: Templates can run shell commands, extending a generator beyond file output. The documented --dry option provides a way to test-run generators; shell execution also makes reviewing template changes important.
• Framework examples: The maker's site presents Redux, Express.js, and React Native use cases, while the Quick Start cites React, Redux, and Node.js as original boilerplate targets. These examples show its intended range without limiting it to those stacks.

Pricing

Hygen is open source under the MIT license and costs nothing. The free offering is the code generator distributed through npm, Homebrew, npx, and standalone binaries; there is no paid tier or free trial to weigh against a usage cap. That makes it a straightforward fit for individual developers and teams comfortable adopting an open-source CLI, rather than buyers seeking a commercial support plan.

Platforms

Hygen is available for Linux, macOS, and Windows. Installation options include Homebrew on macOS, global npm or Yarn installation, npx, and standalone binaries. The maker also points users to Stack Overflow for community help.

Who it's for

Hygen fits developers who repeatedly create similar files or make predictable edits across a project, and teams that want template changes to be reviewed with the code they affect. Its command-line arguments and prompts accommodate both automation and guided generation. It is a weaker fit for teams that depend on automatic discovery of templates in deep folder trees, or need a schema-to-code generator.

Pros and cons

• Pro — Templates stay close to project code: A local template folder lets teams keep shared generator changes in the project repository and review them alongside code.
• Pro — More than file scaffolding: EJS templates, destination frontmatter, prompts, file injection, and shell commands support varied generation and editing workflows.
• Pro — No cost or platform lock-in across the listed systems: The MIT-licensed tool is free and supports Linux, macOS, and Windows.
• Con — Nested template discovery needs extra handling: Hygen does not find templates down folder trees out of the box, which can complicate deeply nested generator layouts.
• Con — CLI-oriented workflow: Hygen offers a CLI, but no IDE plugin; it is not the best match for readers who want generation managed through an editor integration.
• Con — Not for schema-to-code generation: Its template-driven approach does not include schema-to-code generation.

Alternatives

Choose quicktype instead when the task is generating code from data structures: its free offering includes a web app and CLI, and it is open source under Apache-2.0. For Kotlin SQL code generation, SQLDelight is the more focused option; it is an open-source library with no paid tiers stated.

Angular CLI is a better fit when the work is centered on Angular project workflows, while Fern suits readers looking for a free API documentation platform with team, page, AI-credit, page-generation, and site limits. Consider Nx instead for a project tooling and CI workflow with a free Hobby tier capped at 50,000 monthly-reset credits, five contributors, and 10 concurrent CI connections.

Spring Initializr is the alternative to consider for bootstrapping Spring projects. Choose Swagger Codegen when you need API clients, server stubs, or documentation generated from OpenAPI specifications. TypeSpec is another open-source option, with a CLI and online playground.

Browse more options in Code Generators.

Verdict

Choose Hygen if you want a free, project-local CLI for reusable templates, guided prompts, and edits to existing files, especially when the generators should be maintained with application code. Look elsewhere if you need schema-driven output, editor plugins, or automatic discovery through deeply nested template folders.