# Install fern-api with Homebrew Stripe-level SDKs and Docs for your API. Version 5.66.0 via Homebrew; verified 2026-07-08. ## Install ```sh sudo av install brew:fern-api ``` Additional install commands: ### macOS - Homebrew (100%): ```sh brew install fern-api ``` Evidence: local Homebrew formula metadata ## Package facts - **Package key:** brew:fern-api - **Package manager:** Homebrew - **Package manager page:** - **Version:** 5.66.0 - **Source summary:** Stripe-level SDKs and Docs for your API - **Homepage:** - **Repository:** - **Upstream docs:** - **License:** Apache-2.0 - **Source archive:** - **Last updated:** 2026-07-08T03:27:46Z - **Generated:** 2026-07-08T07:18:31+00:00 ## Executables - fern (cli) - fern (alias) ## Dependencies - node ## Install behavior - Post-install hook: not defined - Bottle: available on arm64_linux, arm64_sequoia, arm64_sonoma, arm64_tahoe, sonoma, x86_64_linux ## Freshness - Page generated: 2026-07-08 - Package-manager version: 5.66.0 - Package-manager updated: 2026-07-08 - Local data: ok - Upstream repository: https://buildwithfern.com/ - info: Release/tag comparison is only available for GitHub repositories. ## Project history and usage Fern is an API tooling platform and CLI that turns API definitions into SDKs and documentation. The repository README describes support for OpenAPI, AsyncAPI, Protobuf, and OpenRPC, with generated SDKs in languages such as TypeScript, Python, Java, Go, Ruby, PHP, C#, Swift, and Rust. ### Project history The public Fern repository was created in April 2022, and the `fern-api` npm package was also created in April 2022. Early package history shows rapid 0.0.x CLI publication, while the repository later grew into a monorepo containing CLI code, generators, documentation assets, and platform tooling. By 2026 the package had moved into the 5.x release line, with Homebrew packaging `fern-api` and npm publishing frequent CLI releases. The README frames Fern as a docs-and-SDK workflow rather than only a code generator: users initialize a `fern/` directory, configure generators, and run the CLI to produce SDKs and docs. ### Adoption history Fern's adoption story is tied to API-first developer experience teams that want SDKs and documentation from one source of truth. The README points to public documentation sites built with Fern, including ElevenLabs, LaunchDarkly, and Hume AI, which supports a narrative of production use beyond toy examples. The npm package is the primary CLI distribution channel, while Homebrew gives macOS and Linux users a package-manager-native install path. That combination fits the modern API-tooling pattern where Node-based CLIs are also wrapped for Homebrew users who prefer OS-level package workflows. ### How it is used Typical use starts with `fern init --openapi`, which creates a `fern/` directory containing `fern.config.json`, `generators.yml`, and API definition files. Users then run commands such as `fern check`, `fern add`, and `fern generate`; local generation can run through Docker with `fern generate --local`. Fern is used when an API team wants generated client SDKs, reference documentation, hosted docs, and related developer-experience features to track the API specification. Its package history matters because the CLI is the local entry point to a larger hosted and generator ecosystem. ### Why package nerds care For package maintainers, Fern is a fast-moving Node-distributed CLI whose Homebrew formula follows npm release cadence. That makes it part of the modern class of API development tools where the package is small from the user's perspective but fronts a larger cloud and generator platform. Fern is also notable because its CLI repository documents both generated artifact workflows and the project's own reproducible development setup through DevBox, reflecting the packaging concerns of a polyglot generator stack. ### Timeline - 2022: Public GitHub repository and npm package created. - 2023: Repository README identifies Fern as a Y Combinator 2023 startup. - 2026: npm and Homebrew package metadata show the CLI in the 5.x release line. ### Related projects - Fern belongs to the API specification and SDK generation ecosystem alongside OpenAPI, AsyncAPI, Protobuf, OpenRPC, AWS Smithy, Palantir Conjure, and Stripe-style developer documentation workflows. ### Sources - - - - - ## Security Notes No matching local secret-handling manifest was found for fern-api. Nucleus package metadata is still published here so future coverage has a stable package URL. ## Configuration and credential file locations These source-backed paths show where this package keeps local settings or durable credentials. Automic Vault can use them as review targets for secret scanning, migration, and command approval. ## Configuration files - Unix: fern/fern.config.json, fern/generators.yml ## Source Database Details - **Source Database:** Homebrew formula API - **Tap:** homebrew/core - **Full Name:** fern-api - **Version Scheme:** 0 - **Revision:** 0 - **Bottle Stable Root URL:** - **Deprecated:** no - **Disabled:** no - **Keg Only:** no - **URL Keys:** stable ## Related links - [Terminal utility packages](https://www.automicvault.com/pkg/terminal-utilities/) - Matched terminal and command-line workflow metadata. - [Text processing packages](https://www.automicvault.com/pkg/text-processing-tools/) - Matched text, document, or structured-data processing metadata. - [Developer build packages](https://www.automicvault.com/pkg/developer-build-tools/) - Matched build, compiler, generator, or developer workflow metadata. - [Networking and protocol packages](https://www.automicvault.com/pkg/networking-protocol-tools/) - Matched network, protocol, or remote-service metadata. - [node](https://www.automicvault.com/pkg/brew/node/) - Runtime dependency declared by Homebrew. - [oasdiff](https://www.automicvault.com/pkg/brew/oasdiff/) - Shares av.db curated category or tags: api, cli, developer-tools, openapi. - [algolia](https://www.automicvault.com/pkg/brew/algolia/) - Shares av.db curated category or tags: api, cli, developer-tools. - [kiota](https://www.automicvault.com/pkg/brew/kiota/) - Shares av.db curated category or tags: api, cli, developer-tools, openapi. - [prism-cli](https://www.automicvault.com/pkg/brew/prism-cli/) - Shares av.db curated category or tags: api, cli, developer-tools, openapi. - [redocly-cli](https://www.automicvault.com/pkg/brew/redocly-cli/) - Shares av.db curated category or tags: api, cli, developer-tools, openapi. - [spectral-cli](https://www.automicvault.com/pkg/brew/spectral-cli/) - Shares av.db curated category or tags: api, cli, developer-tools, openapi. - [stripe-cli](https://www.automicvault.com/pkg/brew/stripe-cli/) - Shares av.db curated category or tags: api, cli, developer-tools. - [swag](https://www.automicvault.com/pkg/brew/swag/) - Shares av.db curated category or tags: api, cli, developer-tools, documentation, openapi. - [fern-api](https://www.automicvault.com/pkg/npm/fern-api/) - Same normalized package name appears in another local ecosystem. Shared terms: api, fern, fern-api. - [openapi-generator](https://www.automicvault.com/pkg/brew/openapi-generator/) - Local package facts share a topical domain. Shared terms: api, cli, developer, developer-tools, docs. - [fern-api](https://www.automicvault.com/pkg/npm/fern-api/) - Same normalized package name in another local ecosystem. ## Combined YAML source View the package source record on GitHub. [combined/fern-api.yml](https://github.com/automic-vault/db/blob/main/combined/fern-api.yml) ## Sources - Nucleus package database - Geiger risk classifier - package-page enrichment - curated configuration and credential file locations - curated package history - package version freshness - av.db category and tag curation - package relationship graph - cross-ecosystem install command graph