What is Chapar used for?

Chapar is a fast, native desktop API client for REST, gRPC and GraphQL that stores requests as plain local files with no account. It is a good fit for testing REST and gRPC endpoints locally, and privacy-friendly API client for developers.

Is Chapar open source?

Yes. Chapar is open source under the BSD-3-Clause licence. Its source code is on GitHub at chapar-rest/chapar and is written mainly in Go.

Yes. Chapar is open source, so the software itself is free to use.

What is Chapar an alternative to?

Chapar is an open-source alternative to Postman, Thunder Client and Kreya. Other open-source alternatives to Postman include Bruno, Insomnia and Yaak.

Is Chapar actively maintained?

Yes. The most recent commit to Chapar was on 30 September 2026, and the latest release is v0.9.0, published on 30 September 2026. The project has 714 stars on GitHub.

Chapar: open-source alternative to Postman, Thunder Client

About Chapar

Chapar is a native API testing tool for developers, written in Go and designed to start quickly and stay light. It draws its interface with a GPU-rendered UI toolkit rather than a browser engine, and runs the same on macOS, Linux and Windows. Requests, environments and cookies are plain files on your machine, with no account and no cloud sync.

It supports several protocols. For REST and HTTP it handles every method, query and path parameters and JSON, XML, text, form-data, URL-encoded and binary bodies with syntax highlighting. For gRPC it supports server reflection or proto files, unary and server-streaming methods, metadata and trailers, and TLS with client certificates. GraphQL queries and variables are supported with response data and errors shown separately. Workspaces keep separate collections, requests and environments, and a free hosted mock server is available for trying features. WebSocket and MQTT are planned.

Chapar is licensed under BSD-3-Clause and named after the royal mounted couriers of ancient Persia. It is aimed at developers who want a lightweight, privacy-respecting alternative to heavier API clients.

Key features

REST, gRPC and GraphQL requests
gRPC reflection and proto file support
Workspaces with collections and environments
Plain-file local storage
GPU-rendered native interface
No account or cloud sync

Good fit for

→Testing REST and gRPC endpoints locally
→Privacy-friendly API client for developers

Built with: Go
Tags: api-client; grpc; rest; graphql; golang; desktop-app; api-testing; local-first

Chapar: questions and answers

What is Chapar used for?: Chapar is a fast, native desktop API client for REST, gRPC and GraphQL that stores requests as plain local files with no account. It is a good fit for testing REST and gRPC endpoints locally, and privacy-friendly API client for developers.
Is Chapar open source?: Yes. Chapar is open source under the BSD-3-Clause licence. Its source code is on GitHub at chapar-rest/chapar and is written mainly in Go.
Is Chapar free?: Yes. Chapar is open source, so the software itself is free to use.
What is Chapar an alternative to?: Chapar is an open-source alternative to Postman, Thunder Client and Kreya. Other open-source alternatives to Postman include Bruno, Insomnia and Yaak.
Is Chapar actively maintained?: Yes. The most recent commit to Chapar was on 30 September 2026, and the latest release is v0.9.0, published on 30 September 2026. The project has 714 stars on GitHub.