Relimpact – "Release Impact Analyzer" for Go Projects (API/Docs/Files)

4 months ago 14

Release Impact Analyzer for Go projects - catch breaking API changes, docs updates & important file diffs - fast.

API Diff – Track breaking public API changes (structs, interfaces, functions, constants, variables) to prevent surprises for your users.
Docs Diff – Section-aware, heading-aware Markdown diff to highlight meaningful content changes, not noisy line diffs.
Other Files Diff – Group file changes by extension (.sh, .sql, .json, etc.) to surface important migrations, scripts, and auxiliary file updates.
Designed for Release PR reviews – Helps reviewers quickly see the real impact of changes at a glance.
Human-friendly Markdown Reports – Ready to paste into GitHub Releases, Slack, or changelogs.
Works in GitHub Actions, GitLab CI, or locally – Integrates easily into your CI pipelines or local release process.
No server required – Pure CLI tool. No services to deploy or manage - works entirely from your Git repo and terminal.

relimpact --old=v1.0.0 --new=HEAD > release-impact.md

--- ## API Changes ### Summary | Kind of Change | Count | |-----------------|-------| | Packages Added | 0 | | Packages Removed| 0 | | Funcs Added | 1 | | Funcs Removed | 1 | | Consts Added | 2 | | Consts Removed | 0 | | Types Added | 1 | | Types Removed | 1 | | Fields Added | 1 | | Fields Removed | 1 | | Methods Added | 1 | | Methods Removed | 1 | ### Package Changes #### Package `pkg/mymodule` - Added Funcs: - NewClient(config.Config) -> (*Client, error) - Removed Funcs: - DeprecatedThing() -> (string) - Added Consts: - DefaultTimeout time.Duration - MaxRetries int - Added Types: - ClientOptions - Removed Types: - LegacyClient - Added Fields: - Type `ClientOptions` Fields: - EnableCache bool - Removed Fields: - Type `LegacyClient` Fields: - OldModeEnabled bool - Added Methods: - Client.DoSomething(ctx context.Context) -> error - Removed Methods: - Client.DoSomethingOld() -> bool --- ## Documentation Changes ### Doc File: `README.md` #### Summary: - Headings added: 1 - Headings removed: 0 - Links added: 1 - Links removed: 0 - Images added: 0 - Images removed: 0 - Sections changed: 3 #### Headings added: - Advanced Usage #### Links added: - https://pkg.go.dev/github.com/example/project <details> <summary>Section Word Count Changes (3 changes)</summary> - Section `Quick Start`: 142 -> 155 words - Section `Deprecated Options`: REMOVED (45 words) - Section `New Features`: ADDED (67 words) </details> --- ## Other Files Changes ### `.sql` - Added: - migrations/20240608_add_user_table.sql - Removed: - migrations/20240501_drop_old_index.sql ### `.sh` - Modified: - scripts/deploy.sh

See also docs for more examples.

name: Release Impact on PR on: pull_request: branches: [ master ] types: [ opened, synchronize, reopened ] jobs: release-impact: name: Generate Release Impact Report runs-on: ubuntu-latest steps: - uses: actions/checkout@v4 with: fetch-depth: 0 - name: Determine previous tag id: prevtag run: | git fetch --tags TAG_LIST=$(git tag --sort=-version:refname) PREV_TAG=$(echo "$TAG_LIST" | head -n2 | tail -n1) echo "Previous tag: $PREV_TAG" # Fallback to first tag if no previous if [ -z "$PREV_TAG" ]; then PREV_TAG=$(echo "$TAG_LIST" | head -n1) echo "Fallback to first tag: $PREV_TAG" fi echo "prev_tag=$PREV_TAG" >> $GITHUB_OUTPUT - name: Determine new ref id: newref run: | if [ "${{ github.event_name }}" = "pull_request" ]; then echo "new_ref=${{ github.event.pull_request.head.sha }}" >> $GITHUB_OUTPUT else echo "new_ref=HEAD" >> $GITHUB_OUTPUT fi - uses: hashmap-kz/relimpact-action@main with: old-ref: ${{ steps.prevtag.outputs.prev_tag }} new-ref: ${{ steps.newref.outputs.new_ref }} output: release-impact.md - name: Upload Release Impact Report uses: actions/upload-artifact@v4 with: name: release-impact-${{ github.run_id }}-${{ github.run_attempt }} path: release-impact.md

docker pull quay.io/hashmap_kz/relimpact:latest

Download the latest binary for your platform from the Releases page.
Place the binary in your system's PATH (e.g., /usr/local/bin).

Installation script for Unix-Based OS (requires: tar, curl, jq):

( set -euo pipefail OS="$(uname | tr '[:upper:]' '[:lower:]')" ARCH="$(uname -m | sed -e 's/x86_64/amd64/' -e 's/$arm$$64$\?.*/\1\2/' -e 's/aarch64$/arm64/')" TAG="$(curl -s https://api.github.com/repos/hashmap-kz/relimpact/releases/latest | jq -r .tag_name)" curl -L "https://github.com/hashmap-kz/relimpact/releases/download/${TAG}/relimpact_${TAG}_${OS}_${ARCH}.tar.gz" | tar -xzf - -C /usr/local/bin && \ chmod +x /usr/local/bin/relimpact )

brew tap hashmap-kz/homebrew-tap brew install relimpact

Package-Based installation (suitable in CI/CD)

sudo apt update -y && sudo apt install -y curl curl -LO https://github.com/hashmap-kz/relimpact/releases/latest/download/relimpact_linux_amd64.deb sudo dpkg -i relimpact_linux_amd64.deb

apk update && apk add --no-cache bash curl curl -LO https://github.com/hashmap-kz/relimpact/releases/latest/download/relimpact_linux_amd64.apk apk add relimpact_linux_amd64.apk --allow-untrusted

relimpact helps you understand what really changed between Git refs, in a way that is:

Human-friendly / Structured / Noise-free / Release-ready

Tracks changes to your public exported API:
- struct fields
- interfaces and their methods
- functions
- methods
- constants
- variables
Built on top of Go type system and AST parsing:
- Uses golang.org/x/tools/go/packages to understand the real API, not just text diffs.
- Ignores formatting changes, reordering, comments -> only tracks semantic API impact.
- Detects breaking changes, such as:
  - method signature changes
  - removed fields
  - removed types
  - changed constants
  - new API elements.

Tracks changes in Markdown files:
- any .md in your repo.
Uses Markdown AST parsing:
- Based on goldmark parser.
- Understands:
  - Headings (added / removed)
  - Links (added / removed)
  - Images (added / removed)
  - Section-level word count diffs -> detect real content changes -> not noisy line diffs.
Provides a highly readable report:
- No messy raw git diff output.
- Clear "Section X: 142 -> 155 words" style diffs.
- Great for docs-heavy projects and libraries.

Tracks other file changes, grouped by extension:
- .sh, .sql, .json, .yaml, .conf, .ini, .txt, etc.
Built on top of Git diff:
- Uses git diff --name-status under the hood.
- Groups files per extension -> clean, easy to review.

MIT License. See LICENSE for details.

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