---
title: Go Plugin System
---

Private linters can be added through [Go's plugin system](https://pkg.go.dev/plugin).

For a private linter (which acts as a plugin) to work properly,
the plugin as well as the golangci-lint binary **needs to be built for the same environment**.

`CGO_ENABLED` is another requirement.

This means that `golangci-lint` needs to be built for whatever machine you intend to run it on
(cloning the golangci-lint repository and running a `CGO_ENABLED=1 make build` should do the trick for your machine).

## Create a Plugin

Your linter must provide one or more `golang.org/x/tools/go/analysis.Analyzer` structs.

Your project should also use `go.mod`.

All versions of libraries that overlap `golangci-lint` (including replaced libraries) MUST be set to the same version as `golangci-lint`.
You can see the versions by running `go version -m golangci-lint`.

You'll also need to create a Go file like `plugin/example.go`.

This file MUST be in the package `main`, and MUST define an exposed function called `New` with the following signature:
```go
func New(conf any) ([]*analysis.Analyzer, error) {
	// ...
}
```

See [plugin/example.go](https://github.com/golangci/example-plugin-linter/blob/master/plugin/example.go) for more info.

To build the plugin, from the root project directory, run:
```bash
go build -buildmode=plugin plugin/example.go
```

This will create a plugin `*.so` file that can be copied into your project or another well known location for usage in `golangci-lint`.

## Configure a Plugin

If you already have a linter plugin available, you can follow these steps to define its usage in a projects `.golangci.yml` file.

An example linter can be found at [here](https://github.com/golangci/example-plugin-linter).

If you're looking for instructions on how to configure your own custom linter, they can be found further down.

1. If the project you want to lint does not have one already, copy the [.golangci.yml](https://github.com/golangci/golangci-lint/blob/master/.golangci.yml) to the root directory.
2. Adjust the yaml to appropriate `linters-settings.custom` entries as so:
  ```yaml title=.golangci.yml
  linters-settings:
    custom:
      example:
        path: /example.so
        description: The description of the linter
        original-url: github.com/golangci/example-linter
        settings: # Settings are optional.
          one: Foo
          two:
            - name: Bar
          three:
            name: Bar
  ```

That is all the configuration that is required to run a custom linter in your project.

Custom linters are enabled by default, but abide by the same rules as other linters.

If the disable all option is specified either on command line or in `.golang.yml` files `linters.disable-all: true`, custom linters will be disabled;
they can be re-enabled by adding them to the `linters.enable` list,
or providing the enabled option on the command line, `golangci-lint run -Eexample`.

The configuration inside the `settings` field of linter have some limitations (there are NOT related to the plugin system itself):
we use Viper to handle the configuration but Viper put all the keys in lowercase, and `.` cannot be used inside a key.
