copyrighter

Copyrighter

Copyrighter is a Go build tool that adds a copyright notice to source files. Because a legal notice today keeps the lawyers away.

It recognizes the following source file types:

• Bazel (.bazel)
• C (.c)
• C++ (.cpp)
• C# (.cs)
• CSS (.css)
• Go (.go)
• HTML (.html)
• Java (.java)
• JavaScript (.js)
• PHP (.php)
• PowerShell (.ps1)
• Python (.py)
• Shell (.sh)
• SQL (.sql)
• Terraform (.tf)
• TypeScript (.ts)
• XML (.xml)
• YAML (.yaml, *.yml)

Installation

Copyrighter is distributed as a Go build tool, which requires Go 1.24 or later. From the root directory of your project, add it as a tool dependency:

go get -tool github.com/microbus-io/copyrighter

This records the tool in your go.mod so the version is pinned alongside your other dependencies.

Usage

Place a COPYRIGHT file in the root of the source code directory tree, with:

• The copyright or license notice at the top of the file
• A --- divider
• File matching patterns (optional)

Copyright 2023-yyyy You
All rights reserved

---

!*.*
*.go
!/vendors/*

Then run the tool from the root directory of your project:

go tool copyrighter

Copyright Notice

The notice is the literal text above the --- divider. Blank lines within the notice are preserved; trailing blank lines are trimmed.

The special constant YYYY may be used as a placeholder for the current year, and yyyy for the year in which the file was last modified.

Copyright 2023-YYYY You
All rights reserved

File Matching Patterns

By default, all recognized source file types are processed. To customize which files to process, file matching patterns may be added after the --- divider in COPYRIGHT. Patterns are evaluated in order: the last pattern that matches wins.

Patterns use a .gitignore-style syntax, but with the include/exclude semantics inverted:

• A bare pattern includes matching files.
• A pattern prefixed with ! excludes matching files.
• Lines beginning with # and blank lines are ignored.

The following example excludes all files by default, then re-includes *.go and *.sql files, except in the /vendors directory:

!*.*
*.go
*.sql
!/vendors/*

Patterns that start with a / are anchored to the root directory where COPYRIGHT is located. Otherwise, they apply at any depth.

The following pattern excludes hidden files on Unix:

!.*

The Copyrighter recurses into all descendant subdirectories, except those that contain their own COPYRIGHT file.

Verbose Flag

Pass the -v flag to produce verbose output:

go tool copyrighter -v

Legal

Copyrighter is released by Microbus LLC under the Apache License 2.0.