Backstage Architecture Decision Records Plugin

Architecture Decision Records are short documents that capture important engineering choices. They explain the context, the options you considered, the decision you made, and the consequences. ADRs help future maintainers understand why the system looks the way it does.

The ADR plugin brings those records into Backstage so they sit next to the services they affect. It adds an entity view that lists ADR files from your repo and shows title, status, and date. You can open each ADR as rendered markdown. Relative links and images are rewritten so diagrams and references load as expected. The plugin understands common MADR formats version 2 and version 3. You can tailor file selection and content formatting if your team uses a different template.

Search is built in. Engineers can find ADRs across the catalog and jump straight to the service that owns them. This makes onboarding easier, speeds up reviews, and gives teams a clear history for audits. The plugin works with multiple code hosts through Backstage integrations, and it can serve images from private repos through the backend so content stays accessible.

Step 1: Install the frontend package

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# from your Backstage root
yarn --cwd packages/app add @backstage-community/plugin-adr

Step 2: Add the ADR tab to your entity page

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// packages/app/src/components/catalog/EntityPage.tsx
import { EntityAdrContent, isAdrAvailable } from '@backstage-community/plugin-adr';
import { EntityLayout } from '@backstage/plugin-catalog';

const serviceEntityPage = (
  <EntityLayout>
    {/* other tabs */}
    <EntityLayout.Route if={isAdrAvailable} path="/adrs" title="ADRs">
      <EntityAdrContent />
    </EntityLayout.Route>
  </EntityLayout>
);

export default serviceEntityPage;

Step 3: Annotate your entities with the ADR location

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# catalog-info.yaml
metadata:
  annotations:
    backstage.io/adr-location: docs/adrs

The value can be a path relative to this catalog file or an absolute URL to the directory that holds the ADR markdown files.

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repo-root
  README.md
  src
  catalog-info.yaml
  docs
    adrs
      0001-use-adrs.md
      0002-use-cloud.md

Step 4: Configure integrations in app config

Add the source control hosts you read ADRs from. Here is a simple GitHub entry. Adjust for your hosts.

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# app-config.yaml
integrations:
  github:
    - host: github.com
      token: ${GITHUB_TOKEN}

Step 5a: Install the backend plugin (legacy backend)

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# from your Backstage root
yarn --cwd packages/backend add @backstage-community/plugin-adr-backend

Create the backend router

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// packages/backend/src/plugins/adr.ts
import { createRouter } from '@backstage-community/plugin-adr-backend';
import { Router } from 'express';
import { PluginEnvironment } from '../types';

export default async function createPlugin(
  env: PluginEnvironment,
): Promise<Router> {
  return await createRouter({
    reader: env.reader,
    cacheClient: env.cache.getClient(),
    logger: env.logger,
  });
}

Wire it into the backend

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// packages/backend/src/index.ts
import adr from './plugins/adr';

// inside main startup
const adrEnv = useHotMemoize(module, () => createEnv('adr'));
apiRouter.use('/adr', await adr(adrEnv));

These legacy backend steps come from the backend plugin guide.

Step 5b: Install the backend plugin (new backend system)

If your app uses the new backend system do this instead of Step 5.

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# from your Backstage root
yarn --cwd packages/backend add @backstage-community/plugin-adr-backend

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// packages/backend/src/index.ts
import { createBackend } from '@backstage/backend-defaults';

const backend = createBackend();

backend.add(import('@backstage-community/plugin-adr-backend'));

// other features
backend.start();

Step 7: Add ADRs to search results optional

Install the ADR search backend module

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# from your Backstage root
yarn --cwd packages/backend add @backstage-community/search-backend-module-adr

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// packages/backend/src/index.ts
import { createBackend } from '@backstage/backend-defaults';

const backend = createBackend();

backend.add(import('@backstage/plugin-search-backend/alpha'));
backend.add(import('@backstage-community/search-backend-module-adr'));

backend.start();

You can tune the index schedule under the key search.collators.adr in app config if needed. These steps come from the search module guide.

Step 8: Show ADR results on the search page (optional)

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// packages/app/src/components/search/SearchPage.tsx
import React from 'react';
import { SearchResult } from '@backstage/plugin-search';
import { List } from '@material-ui/core';
import { AdrSearchResultListItem } from '@backstage-community/plugin-adr';
import { AdrDocument } from '@backstage-community/plugin-adr-common';

export const SearchPage = () => (
  <SearchResult>
    {({ results }) => (
      <List>
        {results.map(({ type, document, highlight, rank }) => {
          switch (type) {
            case 'adr':
              return (
                <AdrSearchResultListItem
                  key={document.location}
                  result={document as AdrDocument}
                />
              );
            default:
              return null;
          }
        })}
      </List>
    )}
  </SearchResult>
);

Step 9: Custom ADR filename filter (optional)

If you need to skip template files or enforce a naming scheme add a filter in the entity content

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// packages/app/src/components/catalog/EntityPage.tsx
import { EntityAdrContent } from '@backstage-community/plugin-adr';
import { AdrFilePathFilterFn } from '@backstage-community/plugin-adr-common';

const myCustomFilterFn: AdrFilePathFilterFn = path => {
  if (path === '0000-adr-template.md') return false;
  return /^(decided-adrs\/)?\d{4}-.+\.md$/.test(path);
};

<EntityLayout.Route if={isAdrAvailable} path="/adrs" title="ADRs">
  <EntityAdrContent filePathFilterFn={myCustomFilterFn} />
</EntityLayout.Route>;

Step 10: Custom content decorators (Optional)

You can modify how ADR markdown is rendered while keeping default behavior

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// packages/app/src/components/catalog/EntityPage.tsx
import { EntityAdrContent, AdrReader, AdrContentDecorator } from '@backstage-community/plugin-adr';

const myCustomDecorator: AdrContentDecorator = ({ content, filename }) => {
  if (filename?.includes('security')) {
    return { content: `<!-- masked -->\n${content}` };
  }
  return { content };
};

<EntityLayout.Route if={isAdrAvailable} path="/adrs" title="ADRs">
  <EntityAdrContent
    contentDecorators={[
      AdrReader.decorators.createRewriteRelativeLinksDecorator(),
      AdrReader.decorators.createRewriteRelativeEmbedsDecorator(),
      AdrReader.decorators.createFrontMatterFormatterDecorator(),
      myCustomDecorator,
    ]}
  />
</EntityLayout.Route>;

Backstage Architecture Decision Records Plugin

Installation Instructions

Changelog

Breaking changes

Features

Bug fixes

Maintenance

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