// Markings

Automatically enforce and update source code banner markings.

What are banner markings?

Banner markings are standardized text blocks injected at the top or bottom of source code files. They are commonly used for compliance, such as applying classification levels in defense contexts or managing open-source licensing headers.

markings uses special markings:managed boundaries to safely identify, apply, and update these banners without breaking your code.

// markings:managed
//
// Copyright (c) 2026 Markings Contributors
// SPDX-License-Identifier: MIT
//
// This software is released under the MIT License.
//
// markings:managed

package main

Installation

Download the latest pre-compiled binary for your OS and architecture from the GitHub Releases page.

Alternatively, if you have a local Go toolchain installed, you can build from source:

go install github.com/mharrisb1/markings@latest

Configuration

Create a .markings.yaml file in your repository root to define templates and map them to file types:

Warning

You must use migrate-marker if you set a new value for marker in config for an existing project.

marker: "my-custom-marker:managed" # Optional: defaults to "markings:managed"
mark_empty_files: false # Optional: defaults to false

exclude:
  - "**/.git"
  - "**/node_modules"

templates:
  mit_header: |
    Copyright (c) {{ .Year }} {{ .Author }}
    SPDX-License-Identifier: MIT

data:
  Year: 2026
  Author: Your Name

comment_styles:
  go_line:
    prefix: "// "

rules:
  - id: go-files
    match: "**/*.go"
    header:
      template: mit_header
      newline_after: true
    comment_style: go_line

Template Functions

You can use built-in macros and logic inside your templates.

templates:
  dynamic_header: |
    File: {{ filename }}
    Copyright (c) {{ year }} {{ upper .Company }}

Custom Macros

Function	Description	Example
upper	Returns uppercase string	{{ upper .Name }}
lower	Returns lowercase string	{{ lower .Name }}
title	Returns titlecase string	{{ title .Name }}
trim / trimLeft / trimRight	Removes whitespace	{{ trim .Name }}
trimPrefix / trimSuffix	Removes prefix or suffix	{{ trimPrefix .Name "v" }}
replace	Replaces substring	{{ replace .Name "old" "new" }}
contains	Checks if substring exists	{{ if contains .Name "abc" }}
hasPrefix / hasSuffix	Checks string boundaries	{{ if hasPrefix .Name "test" }}
split	Splits string by separator	{{ split .Name "," }}
join	Joins array into string	{{ join .List "," }}
time	Formats current time (Go style)	{{ time "02/01/06" }}
date	Current date (YYYY-MM-DD)	{{ date }}
year	Current YYYY year	{{ year }}
month	Current MM month	{{ month }}
day	Current DD day	{{ day }}
filename	Current filename	{{ filename }}

Standard Macros

Function	Description	Example
eq / ne	Equal / Not equal	{{ if eq .Role "admin" }}
lt / le	Less than / Less or equal	{{ if lt .Age 18 }}
gt / ge	Greater than / Greater or equal	{{ if gt .Score 90 }}
and / or / not	Logical AND / OR / NOT	{{ if and .A .B }}
len	Length of string, slice, map	{{ len .Users }}
index	Value from map/slice by index	{{ index .List 0 }}
slice	Slices array or string	{{ slice .Name 0 3 }}

Usage

You can pass specific files, directories, or nothing at all (which defaults to scanning the current directory). Files are automatically recursively discovered and filtered against your exclude and include rules.

# Check all files in the current directory recursively
markings check

# Automatically inject or update markings in a specific folder
markings fix src/

# Migrate the entire repository to a new marker
markings migrate-marker "markings:managed"

CI Integrations

You can easily integrate markings into your CI/CD pipelines to automatically check or fix markings. By default, it looks for .markings.yaml in the root, but you can override this.

GitHub Actions

We provide native GitHub Actions to run markings.

steps:
  - uses: actions/checkout@v4

  # Optional: Explicitly install the CLI to your PATH for custom scripts
  # - uses: mharrisb1/markings/setup@v0

  # Automatically check for correct markings
  - uses: mharrisb1/markings/check@v0
    with:
      args: "--config custom/path/.markings.yaml" # Optional arguments


  # Or automatically fix markings
  # - uses: mharrisb1/markings/fix@v0

GitLab CI

You can use the published Docker image to run markings natively in GitLab CI or other Docker-based runners.

markings_check:
  image:
    name: ghcr.io/mharrisb1/markings:v0
    entrypoint: [""]
  script:
    - markings check

Pre-Commit

To automatically enforce or update markings during commits, add the following to your .pre-commit-config.yaml.

repos:
  - repo: https://github.com/mharrisb1/markings
    rev: <VERSION>
    hooks:
      # Automatically fix markings
      - id: markings
        types: [text]
        args: ["--config", "custom/path/.markings.yaml"] # Optional arguments


      # Or just check without modifying
      # - id: markings-check
      #   types: [text]