diff --git a/server/src/discogs.ts b/server/src/discogs.ts
new file mode 100644
index 0000000..de845c9
--- /dev/null
+++ b/server/src/discogs.ts
@@ -0,0 +1,149 @@
+import type { SerialQueue } from './queue.js'
+
+export interface DiscogsReleaseSummary {
+  id: number
+  artist: string
+  title: string
+  year: number | null
+  formats: string[]
+  labels: string[]
+  country: string | null
+  catno: string | null
+  thumbUrl: string | null
+}
+
+export interface DiscogsReleaseFull extends DiscogsReleaseSummary {
+  genres: string[]
+  tracklist: { position: string; title: string }[]
+  coverUrl: string | null
+  barcodes: string[]
+}
+
+export class DiscogsError extends Error {
+  constructor(
+    public status: number,
+    message: string
+  ) {
+    super(message)
+  }
+}
+export class DiscogsAuthError extends DiscogsError {
+  constructor() {
+    super(401, 'discogs token rejected')
+  }
+}
+export class DiscogsRateLimitError extends DiscogsError {
+  constructor() {
+    super(429, 'discogs rate limit hit')
+  }
+}
+
+const USER_AGENT = 'record-shop/0.1.0'
+
+function splitTitle(title: string): { artist: string; title: string } {
+  const idx = title.indexOf(' - ')
+  if (idx === -1) return { artist: '', title }
+  return { artist: title.slice(0, idx), title: title.slice(idx + 3) }
+}
+
+export function toYear(year: unknown): number | null {
+  const n = Number(year)
+  return Number.isInteger(n) && n > 0 ? n : null
+}
+
+export function mapSearchResult(r: any): DiscogsReleaseSummary {
+  const { artist, title } = splitTitle(String(r.title ?? ''))
+  return {
+    id: Number(r.id),
+    artist,
+    title,
+    year: toYear(r.year),
+    formats: Array.isArray(r.format) ? r.format.map(String) : [],
+    labels: Array.isArray(r.label) ? r.label.map(String) : [],
+    country: r.country ?? null,
+    catno: r.catno ?? null,
+    thumbUrl: r.thumb ?? r.cover_image ?? null,
+  }
+}
+
+export function mapRelease(r: any): DiscogsReleaseFull {
+  return {
+    id: Number(r.id),
+    artist: Array.isArray(r.artists) && r.artists[0] ? String(r.artists[0].name) : '',
+    title: String(r.title ?? ''),
+    year: toYear(r.year),
+    formats: Array.isArray(r.formats) ? r.formats.map((f: any) => String(f.name)) : [],
+    labels: Array.isArray(r.labels) ? r.labels.map((l: any) => String(l.name)) : [],
+    country: r.country ?? null,
+    catno: Array.isArray(r.labels) && r.labels[0] ? (r.labels[0].catno ?? null) : null,
+    thumbUrl: r.thumb ?? (r.images?.[0]?.uri ?? null),
+    genres: Array.isArray(r.genres) ? r.genres.map(String) : [],
+    tracklist: Array.isArray(r.tracklist)
+      ? r.tracklist
+          .filter((t: any) => t.title)
+          .map((t: any) => ({ position: String(t.position ?? ''), title: String(t.title) }))
+      : [],
+    coverUrl: r.images?.[0]?.uri ?? null,
+    barcodes: Array.isArray(r.identifiers)
+      ? r.identifiers
+          .filter((i: any) => i.type === 'Barcode' && i.value)
+          .map((i: any) => String(i.value))
+      : [],
+  }
+}
+
+export class DiscogsClient {
+  private token: string
+  private fetchImpl: typeof fetch
+  private baseUrl: string
+  private queue?: SerialQueue
+
+  constructor(token: string, fetchImpl: typeof fetch = fetch, baseUrl = 'https://api.discogs.com', queue?: SerialQueue) {
+    this.token = token
+    this.fetchImpl = fetchImpl
+    this.baseUrl = baseUrl
+    this.queue = queue
+  }
+
+  private async get(path: string, params: Record<string, string> = {}): Promise<any> {
+    const doFetch = async (): Promise<any> => {
+      const url = new URL(`${this.baseUrl}${path}`)
+      for (const [k, v] of Object.entries(params)) url.searchParams.set(k, v)
+      url.searchParams.set('token', this.token)
+      let res: Response
+      try {
+        res = await this.fetchImpl(url.toString(), {
+          headers: {
+            Authorization: `Discogs token=${this.token}`,
+            'User-Agent': USER_AGENT,
+            Accept: 'application/json',
+          },
+        })
+      } catch {
+        throw new DiscogsError(0, 'could not reach api.discogs.com')
+      }
+      if (res.status === 401) throw new DiscogsAuthError()
+      if (res.status === 429) throw new DiscogsRateLimitError()
+      if (!res.ok) throw new DiscogsError(res.status, `discogs HTTP ${res.status}`)
+      return res.json()
+    }
+    return this.queue ? this.queue.run(doFetch) : doFetch()
+  }
+
+  async searchByBarcode(barcode: string): Promise<DiscogsReleaseSummary[]> {
+    const body = await this.get('/database/search', { barcode, type: 'release', per_page: '20' })
+    return (body.results ?? []).map(mapSearchResult)
+  }
+
+  async searchByText(query: string, format?: string): Promise<DiscogsReleaseSummary[]> {
+    const params: Record<string, string> = { q: query, type: 'release', per_page: '20' }
+    if (format) params.format = format
+    const body = await this.get('/database/search', params)
+    return (body.results ?? []).map(mapSearchResult)
+  }
+
+  async getRelease(id: number): Promise<DiscogsReleaseFull> {
+    const body = await this.get(`/releases/${id}`)
+    return mapRelease(body)
+  }
+}
diff --git a/server/test/discogs.test.ts b/server/test/discogs.test.ts
new file mode 100644
index 0000000..90f64cf
--- /dev/null
+++ b/server/test/discogs.test.ts
@@ -0,0 +1,108 @@
+import { describe, it, expect } from 'vitest'
+import {
+  DiscogsClient,
+  DiscogsAuthError,
+  DiscogsRateLimitError,
+  mapSearchResult,
+  mapRelease,
+} from '../src/discogs.js'
+import { discogsSearchFixture, discogsReleaseFixture } from './fixtures.js'
+
+function jsonResponse(body: unknown, status = 200): Response {
+  return new Response(JSON.stringify(body), {
+    status,
+    headers: { 'content-type': 'application/json' },
+  })
+}
+
+function stubFetch(routes: (url: string) => Response): typeof fetch {
+  return (async (input: any) => routes(String(input))) as typeof fetch
+}
+
+describe('DiscogsClient', () => {
+  it('searches by barcode with token and maps results', async () => {
+    const seen: string[] = []
+    const c = new DiscogsClient(
+      'testtoken',
+      stubFetch((url) => {
+        seen.push(url)
+        return jsonResponse(discogsSearchFixture)
+      })
+    )
+    const results = await c.searchByBarcode('5021592210629')
+    expect(seen[0]).toContain('/database/search')
+    expect(seen[0]).toContain('barcode=5021592210629')
+    expect(seen[0]).toContain('type=release')
+    expect(seen[0]).toContain('token=testtoken')
+    expect(results).toHaveLength(2)
+    expect(results[0]).toEqual({
+      id: 1001,
+      artist: 'The Cinematic Orchestra',
+      title: 'Motion',
+      year: 1999,
+      formats: ['CD', 'Album'],
+      labels: ['Ninja Tune'],
+      country: 'UK',
+      catno: 'ZENCD012',
+      thumbUrl: 'https://img.discogs.com/small1.jpg',
+    })
+  })
+
+  it('searches by text with optional format filter', async () => {
+    const seen: string[] = []
+    const c = new DiscogsClient(
+      't',
+      stubFetch((url) => {
+        seen.push(url)
+        return jsonResponse(discogsSearchFixture)
+      })
+    )
+    await c.searchByText('motion', 'Vinyl')
+    expect(seen[0]).toContain('q=motion')
+    expect(seen[0]).toContain('format=Vinyl')
+  })
+
+  it('throws DiscogsAuthError on 401', async () => {
+    const c = new DiscogsClient('bad', stubFetch(() => jsonResponse({ message: 'bad' }, 401)))
+    await expect(c.searchByBarcode('123')).rejects.toBeInstanceOf(DiscogsAuthError)
+  })
+
+  it('throws DiscogsRateLimitError on 429', async () => {
+    const c = new DiscogsClient('t', stubFetch(() => jsonResponse({}, 429)))
+    await expect(c.searchByBarcode('123')).rejects.toBeInstanceOf(DiscogsRateLimitError)
+  })
+
+  it('fetches full release with barcode identifiers', async () => {
+    const c = new DiscogsClient(
+      't',
+      stubFetch((url) => {
+        expect(url).toContain('/releases/1001')
+        return jsonResponse(discogsReleaseFixture)
+      })
+    )
+    const release = await c.getRelease(1001)
+    expect(release.title).toBe('Motion')
+    expect(release.barcodes).toEqual(['5021592210629'])
+    expect(release.coverUrl).toBe('https://img.discogs.com/full1.jpg')
+  })
+})
+
+describe('mappers', () => {
+  it('splits search title into artist/title and parses year', () => {
+    const first = discogsSearchFixture.results[0]!
+    const mapped = mapSearchResult(first)
+    expect(mapped.artist).toBe('The Cinematic Orchestra')
+    expect(mapped.title).toBe('Motion')
+    expect(mapped.year).toBe(1999)
+  })
+
+  it('maps full release', () => {
+    const mapped = mapRelease(discogsReleaseFixture)
+    expect(mapped.formats).toEqual(['CD'])
+    expect(mapped.labels).toEqual(['Ninja Tune'])
+    expect(mapped.tracklist).toEqual([
+      { position: '1', title: 'Overture' },
+      { position: '2', title: 'Theme de Yoyo' },
+    ])
+  })
+})
diff --git a/server/test/fixtures.ts b/server/test/fixtures.ts
new file mode 100644
index 0000000..bee498d
--- /dev/null
+++ b/server/test/fixtures.ts
@@ -0,0 +1,45 @@
+export const discogsSearchFixture = {
+  results: [
+    {
+      id: 1001,
+      type: 'release',
+      title: 'The Cinematic Orchestra - Motion',
+      year: '1999',
+      format: ['CD', 'Album'],
+      label: ['Ninja Tune'],
+      country: 'UK',
+      catno: 'ZENCD012',
+      cover_image: 'https://img.discogs.com/big1.jpg',
+      thumb: 'https://img.discogs.com/small1.jpg',
+    },
+    {
+      id: 1002,
+      type: 'release',
+      title: 'The Cinematic Orchestra - Motion',
+      year: '1999',
+      format: ['Vinyl', '2xLP'],
+      label: ['Ninja Tune'],
+      country: 'UK',
+      catno: 'ZEN012',
+      cover_image: 'https://img.discogs.com/big2.jpg',
+      thumb: 'https://img.discogs.com/small2.jpg',
+    },
+  ],
+}
+
+export const discogsReleaseFixture = {
+  id: 1001,
+  title: 'Motion',
+  artists: [{ name: 'The Cinematic Orchestra' }],
+  year: 1999,
+  formats: [{ name: 'CD', qty: '1' }],
+  labels: [{ name: 'Ninja Tune', catno: 'ZENCD012' }],
+  genres: ['Electronic', 'Jazz'],
+  country: 'UK',
+  images: [{ uri: 'https://img.discogs.com/full1.jpg' }],
+  tracklist: [
+    { position: '1', title: 'Overture' },
+    { position: '2', title: 'Theme de Yoyo' },
+  ],
+  identifiers: [{ type: 'Barcode', value: '5021592210629' }],
+}