custom_lint review
A free, open-source toolkit for authoring and testing custom Dart lints, but no longer actively developed.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
custom_lint is an open-source Dart package from Invertase for developers and teams that need to create and apply their own lint rules in Dart and Flutter projects. It supports custom rule development through custom_lint_builder, with a command-line runner for analysis and CI. That makes it a fit for package authors or teams with conventions that generic lint collections do not cover, rather than a ready-made, broad ruleset for teams seeking prewritten checks.
Rule authoring comes with practical development tools: lint rules can be tested with expect_lint, plugin behavior can be debugged with the Dart debugger, and lint plugins support hot reload and hot restart. Projects can enable or disable individual rules, set options for rules that expose them, and use // ignore and // ignore_for_file comments. Quick fixes and assists extend the workflow beyond reporting diagnostics. It supports Flutter projects and lists Visual Studio Code among its integrations; the package also provides CLI analysis for CI and is self-hosted.
The main consideration is maintenance status: the repository was archived on March 24, 2026, says the project is no longer under active development, and recommends Dart’s analysis_server_plugin for new custom lints. Buyers starting a new linting project should weigh that recommendation before adopting custom_lint. It is more appropriate for teams that specifically need its custom-rule authoring and testing capabilities and can account for the project’s status; teams looking for an actively developed foundation for new plugins should consider the recommended alternative instead.
custom_lint pros and cons
- Where it wins
- Build, configure, and selectively enable custom lint rules.
- Includes CLI analysis, rule tests, quick fixes, and assists.
- Supports Flutter projects, plugin debugging, and hot reload.
- Where it doesn't
- No longer under active development; new lints are directed to analysis_server_plugin.
- Focused on custom rules rather than a broad prebuilt ruleset.
- Its listed IDE integration is Visual Studio Code.
custom_lint fact sheet, pricing and score →
Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.
Last updated · How we research and update