What is Dockerfile Roast used for?

Dockerfile Roast is an opinionated Dockerfile linter written in Rust that flags bad practices with blunt messages, with editor plugins, a web version and CI support. It is a good fit for linting Dockerfiles in CI pipelines and catching container build mistakes while editing.

Is Dockerfile Roast open source?

Yes. Dockerfile Roast is open source under the MIT licence. Its source code is on GitHub at immanuwell/dockerfile-roast and is written mainly in Rust.

Is Dockerfile Roast free?

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

What are some alternatives to Dockerfile Roast?

Similar open-source tools in the CI/CD & DevOps category include actionlint, kube-score and Act. SaaS products in the same category include Blacksmith, Depot and Sonatype Nexus Repository.

Is Dockerfile Roast actively maintained?

Yes. The most recent commit to Dockerfile Roast was on 1 September 2026, and the latest release is 1.7.0, published on 1 September 2026. The project has 1.1k stars on GitHub.

Dockerfile Roast: open-source CI/CD & DevOps

About Dockerfile Roast

droast, short for Dockerfile Roast, is a linter for Dockerfiles that has strong opinions. It catches bad practices and reports them in a deliberately blunt tone, like feedback from a senior engineer who has seen too many production incidents. It is written in Rust.

Its parser is span-aware and understands heredocs, parser and escape directives, shell and JSON forms, BuildKit flags such as RUN --mount, Windows paths and PowerShell, and it reports malformed syntax under its own rule code. Findings can be tuned with presets, for example a production preset, and a comparison page explains how it differs from other linters.

You can use it through a VS Code extension with inline diagnostics, a Neovim plugin, a GitHub Action, a Docker image, a binary, Homebrew, Cargo, Wasmer or a browser-based linter built on WebAssembly. A Rust library is available for embedding it in other tools. The project is MIT licensed.

Key features

Opinionated Dockerfile linting with blunt messages
Span-aware parser for heredocs and BuildKit flags
VS Code extension with inline diagnostics
Neovim plugin with lint-on-save
Web linter running in the browser via WASM
Docker image, Homebrew, Cargo and Wasmer installs
GitHub Action for CI

Good fit for

→Linting Dockerfiles in CI pipelines
→Catching container build mistakes while editing

Built with: Rust; Docker
Tags: dockerfile; linter; docker; rust; static-analysis; ci; security; devops; wasm

Dockerfile Roast: questions and answers

What is Dockerfile Roast used for?: Dockerfile Roast is an opinionated Dockerfile linter written in Rust that flags bad practices with blunt messages, with editor plugins, a web version and CI support. It is a good fit for linting Dockerfiles in CI pipelines and catching container build mistakes while editing.
Is Dockerfile Roast open source?: Yes. Dockerfile Roast is open source under the MIT licence. Its source code is on GitHub at immanuwell/dockerfile-roast and is written mainly in Rust.
Is Dockerfile Roast free?: Yes. Dockerfile Roast is open source, so the software itself is free to use.
What are some alternatives to Dockerfile Roast?: Similar open-source tools in the CI/CD & DevOps category include actionlint, kube-score and Act. SaaS products in the same category include Blacksmith, Depot and Sonatype Nexus Repository.
Is Dockerfile Roast actively maintained?: Yes. The most recent commit to Dockerfile Roast was on 1 September 2026, and the latest release is 1.7.0, published on 1 September 2026. The project has 1.1k stars on GitHub.