Rattler

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What Rattler is

Rattler is a Rust library for developers building tools that work with the Conda ecosystem without depending on Python. Its components can solve environments, download and extract packages, create environments, and activate them to run programs. Language bindings make those workflows available outside Rust: py-rattler can be installed through pip or conda and is designed for asyncio, while the @conda-org/rattler JavaScript package is compiled to WebAssembly and can run in browsers or Node.js. The bindings can solve, install, and run commands in Conda environments. Rattler also includes networking for authentication and mirroring, plus a component that discovers, fetches, and verifies Sigstore attestations for Conda packages. Pixi, rattler-build, and the prefix.dev backend use it. The public repository lists a BSD-3-Clause license. The maker offers enterprise builds for Linux, macOS, and Windows, with contracted support and security materials available. For questions, maintainers direct users to their Discord community.

Who it suits

Rattler is aimed at developers building Conda-related workflows into tools or applications, particularly those working in Rust or using its Python and JavaScript bindings. Enterprise teams may also consider its contracted support and security materials.

What it does well

Builds Conda workflows without requiring Python.
Rust library with Python and JavaScript bindings.
JavaScript package runs in browsers or Node.js.
Includes Sigstore attestation verification for Conda packages.
Repository lists a BSD-3-Clause license.

What to know first

Questions are directed to the Discord community.
Enterprise support is contracted rather than described as standard support.

Getting started

Visit https://prefix.dev/rattler.
For Python bindings, install py-rattler with `pixi add py-rattler` or `uv add py-rattler`.
For JavaScript, use the @conda-org/rattler package, which runs in browsers or Node.js.
Ask questions in the maintainers’ Discord community.

Verdict

Rattler provides reusable Conda environment and package workflows across Rust and other languages. It is most relevant when you are building a tool or application, rather than looking for a standalone end-user app.

Questions

What does Rattler do?

It provides components for solving Conda environments, downloading and extracting packages, creating environments, and activating them to run programs.

Does Rattler require Python?

The library is built to work with the Conda ecosystem without depending on Python. Python bindings are available separately as py-rattler.

Is Rattler open source?

Yes. Its public repository lists a BSD-3-Clause license.

Can JavaScript applications use Rattler?

Yes. The @conda-org/rattler package is compiled to WebAssembly and can run in browsers or Node.js.

What support is available?

The maintainers direct questions to their Discord community. Contracted enterprise support can include agreed response times, issue triage, fixes, and direct maintainer access.

Facts from Rattler's own pages

Additional bindings: The Rattler repository says its Python and JavaScript bindings can solve, install, and run commands in Conda environments. · github.com, 8 Oct 2026
Conda channel example: The maker’s Python example solves package specifications using the conda-forge channel. · prefix.dev, 8 Oct 2026
Enterprise security materials: The maker says it can provide a DPA, SBOM and provenance per release, and its CVE remediation policy. · prefix.dev, 8 Oct 2026
Enterprise support: The maker offers contracted support for Rattler with agreed response times, issue triage, fixes, and direct maintainer access. · prefix.dev, 8 Oct 2026
Install Python bindings: The maker’s page shows installing py-rattler with either `pixi add py-rattler` or `uv add py-rattler`. · prefix.dev, 8 Oct 2026
Integrations: Rattler is used by Pixi, rattler-build, and the prefix.dev backend. · github.com, 8 Oct 2026
Intended users: The maker presents Rattler as a library for developers building custom Conda-related tools and applications. · prefix.dev, 8 Oct 2026
JavaScript bindings: The @conda-org/rattler JavaScript package is compiled to WebAssembly and can run in browsers or Node.js. · github.com, 8 Oct 2026
JavaScript integration: The repository says the JavaScript package is compiled to WebAssembly and can run in a browser or Node.js. · github.com, 8 Oct 2026
Language and API: Rattler is written in Rust and provides bindings for other languages. · github.com, 8 Oct 2026
License: The repository identifies its license as BSD-3-Clause. · github.com, 8 Oct 2026
Networking: Rattler includes networking functionality for authentication and mirroring. · github.com, 8 Oct 2026
Open source: Rattler’s public GitHub repository describes it as Rust crates for the Conda ecosystem and lists a BSD-3-Clause license. · github.com, 8 Oct 2026
Package workflows: Its components can solve environments, download and extract packages, create environments, and activate them to run programs. · github.com, 8 Oct 2026
Purpose: Rattler is a set of Rust crates for building custom applications that use Conda packages and environments. · prefix.dev, 8 Oct 2026
Python bindings: Python bindings expose Rattler’s functionality for programmatic interaction with Conda environments. · prefix.dev, 8 Oct 2026
Security feature: A Rattler component discovers, fetches, and verifies Sigstore attestations for Conda packages. · github.com, 8 Oct 2026
Support: The maintainers direct users with questions to their Discord community. · github.com, 8 Oct 2026
Supported platforms: The maker says enterprise builds covering Rattler are available on Linux, macOS, and Windows. · prefix.dev, 8 Oct 2026
Used by: The maker says Rattler is a core building block for Pixi, rattler-build, and the prefix.dev website backend. · prefix.dev, 8 Oct 2026

Where Rattler stands on Freedom251

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