Introduction

conventional-changelog-writer renders already-parsed commits into changelog text. It’s the final stage of the pipeline — parser → filter → writer — and the engine behind conventional-changelog. What the output looks like is controlled entirely by the options you pass; presets are ready-made option sets.

Quick start

1. Install conventional-changelog-writer:

   pnpm

   pnpm add conventional-changelog-writer

   npm

   npm i conventional-changelog-writer

   yarn

   yarn add conventional-changelog-writer

2. Provide parsed commits. The writer consumes parsed commit objects, like those produced by conventional-commits-parser:

   const commits = [
     {
       type: 'feat',
       scope: 'api',
       subject: 'add async write() generator',
       header: 'feat(api): add async write() generator',
       hash: '0f7e2c1a9d3e4b5c6f7089abcdef0123456789ab',
       notes: [],
       references: []
     },
     {
       type: 'fix',
       scope: 'cli',
       subject: 'resolve config path relative to cwd',
       header: 'fix(cli): resolve config path relative to cwd',
       hash: 'a3b9d8472e1f0c9b8a7d6e5f4c3b2a1908f7e6d5',
       notes: [],
       references: []
     }
   ]

3. Render the changelog. writeChangelogString(commits, context?, options?) returns it as a string; the context supplies the version and repository:

   import { writeChangelogString } from 'conventional-changelog-writer'
   
   const changelog = await writeChangelogString(commits, {
     version: '1.2.0',
     repoUrl: 'https://github.com/acme/app'
   })
   
   console.log(changelog)

   Out of the box the writer groups commits by their raw type and prints each commit’s full header — deliberately minimal, because formatting is meant to come from options:

   CHANGELOG.md

   ## 1.2.0 (2026-07-01)
   
   ### feat
   
   * feat(api): add async write() generator ([0f7e2c1](https://github.com/acme/app/commits/0f7e2c1))
   
   ### fix
   
   * fix(cli): resolve config path relative to cwd ([a3b9d84](https://github.com/acme/app/commits/a3b9d84))

4. Format it with a preset. A preset’s writer options map types to sections, format links, and choose a template. Pass them as the third argument:

   import { writeChangelogString } from 'conventional-changelog-writer'
   import createPreset from 'conventional-changelog-conventionalcommits'
   
   const preset = createPreset()
   
   const changelog = await writeChangelogString(commits, {
     version: '1.2.0',
     repoUrl: 'https://github.com/acme/app'
   }, preset.writer)

   CHANGELOG.md

   ## 1.2.0 (2026-07-01)
   
   ### Features
   
   * **api:** add async write() generator ([0f7e2c1](https://github.com/acme/app/commit/0f7e2c1a9d3e4b5c6f7089abcdef0123456789ab))
   
   ### Bug Fixes
   
   * **cli:** resolve config path relative to cwd ([a3b9d84](https://github.com/acme/app/commit/a3b9d8472e1f0c9b8a7d6e5f4c3b2a1908f7e6d5))

See the JS API for every option — template, groupBy, transform, sorting, and more — when you want to shape the output yourself.

Streaming

For large histories you can stream commits instead of buffering them. writeChangelog returns an async-generator function, and writeChangelogStream a Node.js Transform:

import { writeChangelog, writeChangelogStream } from 'conventional-changelog-writer'
import { pipeline } from 'node:stream/promises'

// Async iterable
await pipeline(
  commitsStream,
  writeChangelog(context, options),
  async function* (changelog) {
    for await (const chunk of changelog) {
      process.stdout.write(chunk)
    }
  }
)

// Node.js stream
commitsStream
  .pipe(writeChangelogStream(context, options))
  .pipe(process.stdout)

The CLI wraps these to render a changelog from a stream of commits on the command line.