Open Source Postman Alternatives: Hoppscotch, Bruno and Insomnia Compared

Why are developers leaving Postman?

Postman grew from a lightweight request tool into a cloud collaboration platform. For many teams that means required accounts, collections synced to a vendor cloud, and pricing tied to seats and workspace features.

The other pressure is security. API collections often contain tokens, internal hostnames and example payloads with customer data. Keeping them on local disk or in your own git repository is simpler to audit than a third-party sync service.

Open source clients answer both points. They run locally or on your own server, and several of them treat a collection as ordinary files you can review in a pull request.

Switching is also cheaper than it used to be. Every serious alternative imports Postman collections, so the real migration work is scripts, habits and team conventions, not re-typing requests.

Which open source API clients replace Postman?

Other names come up in the same searches, such as HTTPie, Yaak and the REST Client extension for VS Code. Check each licence and storage model before adopting them.

How does Bruno work?

Bruno stores each request as a small text file in its own markup format inside a folder on disk. A collection is just a directory, so you commit it to the same repository as the API and review changes like any other diff.

It is offline-first and does not require an account. Environments and secrets are kept separately, so you can keep real tokens out of git while sharing the request definitions.

The CLI runs collections in CI, which makes Bruno useful for smoke tests after a deploy. The trade-off is collaboration: there is no live shared workspace, only whatever your git workflow provides.

Scripting is supported through JavaScript for pre-request and post-response logic, and assertions can check status codes or response bodies. Keep those scripts short; long scripts inside request files become hard to review, and logic that complex usually belongs in a proper test suite.

How do Hoppscotch and Insomnia work?

Hoppscotch started as a web app and remains the fastest way to fire a request without installing anything. It supports REST, GraphQL, WebSocket, Server-Sent Events and more from the same interface.

For teams, the self-hosted edition adds accounts, shared workspaces and collections stored in your own database. You run it with Docker alongside Postgres and put it behind your SSO or network rules.

Browser-based clients hit CORS and localhost limits, so Hoppscotch provides a proxy and browser extension, plus a desktop app. Plan which of these your team will standardise on.

Insomnia, maintained by Kong, is a mature desktop client with strong OpenAPI design features, environment chaining and plugins. It feels closest to Postman for people who want a familiar desktop workflow.

Its storage options include a local-only vault, cloud sync and git sync. Past changes around mandatory accounts pushed some users away, so read the current storage defaults and confirm local-only mode fits your policy.

The Inso CLI lets you lint specs and run tests in CI, which pairs well with teams that design APIs spec-first.

In short: Hoppscotch optimises for speed and shared self-hosted workspaces, while Insomnia optimises for a rich desktop experience and API design. Neither stores collections as simple reviewable files by default the way Bruno does, which is the main axis most teams end up deciding on.

How do you choose an API client for your team?

• Decide where collections must live: git repository, self-hosted server, or local only.
• List the protocols you need today: REST, GraphQL, gRPC, WebSocket, SSE.
• Check how secrets are separated from shared request definitions.
• Test the CLI in your CI pipeline before committing to a tool.
• Import one real Postman collection and see what breaks: scripts, auth helpers, variables.
• Pick one default for the team; mixing three clients multiplies maintenance.

Common mistakes when migrating from Postman

• Assuming scripts port cleanly: pre-request and test scripts often use Postman-specific APIs and need rewriting.
• Committing secrets: exporting environments straight into git leaks tokens. Keep secret values in local files or a vault.
• Skipping the CLI: without running collections in CI, they drift from the real API within weeks.
• Migrating everything at once: move the collections people use daily first, archive the rest.
• Ignoring AI-generated clients: if an LLM writes requests for you, make sure its output lands in the shared format, not in personal scratch files.

Where do API clients fit in an AI workflow?

When you build agents that call tools or MCP servers, a plain-file API collection doubles as documentation the model can read. A Bruno folder or an OpenAPI spec in the repo gives a coding assistant exact endpoints, headers and example bodies.

The same files also become regression tests for the tools your agent depends on. If an upstream API changes, a failing CLI run in CI tells you before the agent starts producing confusing errors in production.

One caution: do not let a coding assistant read environment files that hold real credentials. Point it at the request definitions and a sample environment only, and keep production tokens in a secret manager the model never sees.

What features matter most in an API client?

Treat this as a starting point rather than a final verdict. All three projects release often, so confirm the current behaviour in each tool’s documentation before you standardise.

How do you set up a git-based API workflow?

This keeps documentation, tests and the API in lockstep. New team members clone the repository and get a working set of requests on day one, without asking anyone to share a workspace.

A web client runs in your browser, so requests to internal hosts either go through a proxy or need a browser extension or desktop app. If you use a public proxy, your request data passes through someone else’s server.

For internal or sensitive APIs, self-host the proxy and the app, or use a desktop client. That one decision removes most of the security objections teams raise about browser-based tools.

• Create an api-collections folder in the service repository, not in a separate repo nobody updates.
• Commit request definitions and a sample environment with placeholder values only.
• Load real secrets from a local environment file listed in .gitignore, or from your secret manager.
• Add a CI job that runs the smoke-test folder against staging after each deploy.
• Require collection updates in the same pull request that changes an endpoint.
• Review collection diffs like code: renamed fields and removed headers are easy to spot.

Frequently asked questions

Is Bruno free for commercial use?

Bruno’s core app is released under the MIT licence, which permits commercial use. The project also sells an optional paid edition with extra features. Check the current licence file and edition comparison before rolling it out company-wide.

Can I import Postman collections into these tools?

Yes. Bruno, Hoppscotch and Insomnia all offer importers for Postman collections. Requests, folders and variables usually come through well, while pre-request and test scripts may need manual fixes because they depend on Postman’s scripting API.

Can Hoppscotch be self-hosted?

Yes. Hoppscotch publishes a self-hosted edition you run with Docker and a Postgres database. It adds user accounts, team workspaces and an admin dashboard, so collections stay on infrastructure you control rather than a vendor cloud.

Which Postman alternative works best with git?

Bruno is designed around git: every request is a readable text file, so diffs and code reviews work naturally. Insomnia offers git sync as an option, while Hoppscotch keeps data in the browser or its own database rather than in files.