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.

Install the frontend plugin

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

Add the ADR tab to Entity pages

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

// add to each entity page layout you use
export const serviceEntityPage = (
  <EntityLayout>
    {/* other tabs */}
    <EntityLayout.Route if={isAdrAvailable} path="/adrs" title="ADRs">
      <EntityAdrContent />
    </EntityLayout.Route>
  </EntityLayout>
);

Add ADR results to Search

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// packages/app/src/components/search/SearchPage.tsx
import React from 'react';
import { List } from '@material-ui/core';
import { SearchResult } from '@backstage/plugin-search-react';
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}
                  highlight={highlight}
                  rank={rank}
                />
              );
            default:
              return null;
          }
        })}
      </List>
    )}
  </SearchResult>
);

Install the backend plugin for the old backend system

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

Create the plugin 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 the router into the backend

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

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

Install the backend plugin for the new backend system

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

const backend = createBackend();

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

// other features

backend.start();

Configure integrations

Add your source control hosts under integrations in app config. Here is a GitHub example.

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

Annotate entities with the ADR location

Add the annotation to each entity that has ADRs.

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# catalog-info.yaml
apiVersion: backstage.io/v1alpha1
kind: Component
metadata:
  name: my-service
  annotations:
    backstage.io/adr-location: docs/adrs
spec:
  type: service
  owner: team-a
  lifecycle: production

The path is relative to the catalog file. You can use an absolute URL if you store ADRs outside the repo.

Example layout

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

Add ADRs to Search with the new backend system

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();

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

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

backend.start();

Optional config for the collator

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# app-config.yaml
search:
  collators:
    adr:
      schedule:
        frequency: { minutes: 30 }
        timeout: { minutes: 10 }

Optional frontend tweaks

You can filter which files show up. You can also decorate the rendered content.

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

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

export const serviceEntityPage = (
  <EntityLayout>
    <EntityLayout.Route path="/adrs" title="ADRs">
      <EntityAdrContent filePathFilterFn={myFilter} />
    </EntityLayout.Route>
  </EntityLayout>
);

Use content decorators if you need to transform markdown before rendering.

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

const myDecorator = ({ content, filename }: { content: string; filename?: string }) => {
  if (filename?.includes('security')) {
    return { content: `> Security review required\n\n${content}` };
  }
  return { content };
};

export const serviceEntityPage = (
  <EntityLayout>
    <EntityLayout.Route path="/adrs" title="ADRs">
      <EntityAdrContent
        contentDecorators={[
          AdrReader.decorators.createRewriteRelativeLinksDecorator(),
          AdrReader.decorators.createRewriteRelativeEmbedsDecorator(),
          AdrReader.decorators.createFrontMatterFormatterDecorator(),
          myDecorator,
        ]}
      />
    </EntityLayout.Route>
  </EntityLayout>
);

Backstage Architecture Decision Records Plugin

Installation Instructions

Install the frontend plugin

Add the ADR tab to Entity pages

Add ADR results to Search

Install the backend plugin for the old backend system

Install the backend plugin for the new backend system

Configure integrations

Annotate entities with the ADR location

Add ADRs to Search with the new backend system

Optional frontend tweaks

Changelog

Breaking changes

Features

Bug fixes

Maintenance

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