diff --git a/src/http/client.test.ts b/src/http/client.test.ts
new file mode 100644
index 0000000..430db71
--- /dev/null
+++ b/src/http/client.test.ts
@@ -0,0 +1,129 @@
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import { createClient, HTTPError, TimeoutError } from './client'
+
+/** A fetch stub that respects an AbortSignal, the way a real fetch would. */
+function hangingFetch(): typeof fetch {
+  return ((_input: unknown, init?: RequestInit) => {
+    return new Promise((_resolve, reject) => {
+      const signal = init?.signal
+      if (!signal) return
+      if (signal.aborted) {
+        reject(signal.reason)
+        return
+      }
+      signal.addEventListener('abort', () => reject(signal.reason))
+    })
+  }) as typeof fetch
+}
+
+afterEach(() => {
+  vi.unstubAllGlobals()
+})
+
+describe('createClient', () => {
+  it('GETs and returns a Response with the body intact', async () => {
+    vi.stubGlobal(
+      'fetch',
+      async () => new Response('hello', { status: 200, headers: { 'content-type': 'text/plain' } }),
+    )
+    const client = createClient()
+
+    const response = await client.get('https://example.test/')
+
+    expect(response.status).toBe(200)
+    expect(await response.text()).toBe('hello')
+  })
+
+  it('POSTs a JSON body', async () => {
+    let seenBody: string | undefined
+    vi.stubGlobal('fetch', async (_input: unknown, init?: RequestInit) => {
+      seenBody = init?.body as string | undefined
+      return new Response('', { status: 200 })
+    })
+    const client = createClient()
+
+    await client.post('https://example.test/', { json: { a: 1 } })
+
+    expect(seenBody).toBe(JSON.stringify({ a: 1 }))
+  })
+
+  it('throws HTTPError for a non-2xx status by default', async () => {
+    vi.stubGlobal('fetch', async () => new Response('not found', { status: 404 }))
+    const client = createClient({ retry: 0 })
+
+    const error = await client.get('https://example.test/').catch((cause) => cause)
+
+    expect(error).toBeInstanceOf(HTTPError)
+    expect(error.response.status).toBe(404)
+    expect(error.body).toBe('not found')
+  })
+
+  it('resolves with the response instead of throwing when throwHttpErrors is false', async () => {
+    vi.stubGlobal('fetch', async () => new Response('nope', { status: 404 }))
+    const client = createClient({ retry: 0 })
+
+    const response = await client.get('https://example.test/', { throwHttpErrors: false })
+
+    expect(response.status).toBe(404)
+  })
+
+  it('retries a retryable status code and returns the eventual success', async () => {
+    let calls = 0
+    vi.stubGlobal('fetch', async () => {
+      calls++
+      if (calls < 3) return new Response('', { status: 503 })
+      return new Response('ok', { status: 200 })
+    })
+    const client = createClient({ retry: 2 })
+
+    const response = await client.get('https://example.test/')
+
+    expect(calls).toBe(3)
+    expect(response.status).toBe(200)
+  })
+
+  it('stops retrying once the budget runs out and throws the last failure', async () => {
+    let calls = 0
+    vi.stubGlobal('fetch', async () => {
+      calls++
+      return new Response('', { status: 503 })
+    })
+    const client = createClient({ retry: 2 })
+
+    const error = await client.get('https://example.test/').catch((cause) => cause)
+
+    // The first attempt plus 2 retries, then it gives up.
+    expect(calls).toBe(3)
+    expect(error).toBeInstanceOf(HTTPError)
+    expect(error.response.status).toBe(503)
+  })
+
+  it('does not retry a non-retryable status code', async () => {
+    let calls = 0
+    vi.stubGlobal('fetch', async () => {
+      calls++
+      return new Response('', { status: 404 })
+    })
+    const client = createClient({ retry: 2 })
+
+    await expect(client.get('https://example.test/')).rejects.toThrow(HTTPError)
+    expect(calls).toBe(1)
+  })
+
+  it('throws TimeoutError when the request exceeds its timeout', async () => {
+    vi.stubGlobal('fetch', hangingFetch())
+    const client = createClient({ timeout: 20, retry: 0 })
+
+    await expect(client.get('https://example.test/')).rejects.toThrow(TimeoutError)
+  })
+
+  it('getBuffer reads the response body into a Buffer', async () => {
+    vi.stubGlobal('fetch', async () => new Response('hello', { status: 200 }))
+    const client = createClient()
+
+    const buffer = await client.getBuffer('https://example.test/')
+
+    expect(Buffer.isBuffer(buffer)).toBe(true)
+    expect(buffer.toString()).toBe('hello')
+  })
+})
diff --git a/src/render/avatar.test.ts b/src/render/avatar.test.ts
index b93d0fe..5efc5b0 100644
--- a/src/render/avatar.test.ts
+++ b/src/render/avatar.test.ts
@@ -3,6 +3,8 @@ import { fileURLToPath } from 'node:url'
 import { afterEach, describe, expect, it, vi } from 'vitest'
 import type { AvatarFetcher } from './avatar'
 import {
+  containRect,
+  coverRect,
   drawAvatar,
   loadAvatar,
   resetFilterDetectionForTests,
@@ -154,6 +156,87 @@ describe('loadAvatar', () => {
   })
 })
 
+describe('coverRect', () => {
+  it('crops a wide image down to match a square box', () => {
+    const rect = coverRect(200, 100, { x: 0, y: 0, width: 100, height: 100 })
+    expect(rect).toEqual({ sx: 50, sy: 0, sw: 100, sh: 100 })
+  })
+
+  it('crops a tall image down to match a square box', () => {
+    const rect = coverRect(100, 200, { x: 0, y: 0, width: 100, height: 100 })
+    expect(rect).toEqual({ sx: 0, sy: 50, sw: 100, sh: 100 })
+  })
+
+  it('uses the whole image when its aspect ratio already matches the box', () => {
+    const rect = coverRect(100, 100, { x: 0, y: 0, width: 50, height: 50 })
+    expect(rect).toEqual({ sx: 0, sy: 0, sw: 100, sh: 100 })
+  })
+})
+
+describe('containRect', () => {
+  it('letterboxes a wide image top and bottom in a square box', () => {
+    const rect = containRect(200, 100, { x: 0, y: 0, width: 100, height: 100 })
+    expect(rect).toEqual({ x: 0, y: 25, width: 100, height: 50 })
+  })
+
+  it('letterboxes a tall image left and right in a square box', () => {
+    const rect = containRect(100, 200, { x: 0, y: 0, width: 100, height: 100 })
+    expect(rect).toEqual({ x: 25, y: 0, width: 50, height: 100 })
+  })
+
+  it('fits exactly, offset with the box, when the aspect ratio already matches', () => {
+    const rect = containRect(100, 100, { x: 10, y: 20, width: 50, height: 50 })
+    expect(rect).toEqual({ x: 10, y: 20, width: 50, height: 50 })
+  })
+})
+
+describe('drawAvatar', () => {
+  it('clips to a circle when shape is circle, leaving the box corners untouched', async () => {
+    const canvas = createCanvas(10, 10)
+    const ctx = canvas.getContext('2d')
+    const image = await loadAvatar(redSquare())
+
+    drawAvatar(ctx, image, {
+      theme: {
+        grayscale: false,
+        position: 'left',
+        widthRatio: 1,
+        fit: 'cover',
+        shape: 'circle',
+        fallback: null,
+      },
+      box: { x: 0, y: 0, width: 10, height: 10 },
+    })
+
+    const corner = ctx.getImageData(0, 0, 1, 1).data
+    const center = ctx.getImageData(5, 5, 1, 1).data
+
+    expect(corner[3]).toBe(0)
+    expect(center[3]).toBe(255)
+  })
+
+  it('does not clip when shape is rectangle', async () => {
+    const canvas = createCanvas(10, 10)
+    const ctx = canvas.getContext('2d')
+    const image = await loadAvatar(redSquare())
+
+    drawAvatar(ctx, image, {
+      theme: {
+        grayscale: false,
+        position: 'left',
+        widthRatio: 1,
+        fit: 'cover',
+        shape: 'rectangle',
+        fallback: null,
+      },
+      box: { x: 0, y: 0, width: 10, height: 10 },
+    })
+
+    const corner = ctx.getImageData(0, 0, 1, 1).data
+    expect(corner[3]).toBe(255)
+  })
+})
+
 describe('drawAvatar grayscale fallback (no ctx.filter support)', () => {
   afterEach(() => {
     resetFilterDetectionForTests()
diff --git a/src/text/breakpoint.test.ts b/src/text/breakpoint.test.ts
index 8bad8ed..087d563 100644
--- a/src/text/breakpoint.test.ts
+++ b/src/text/breakpoint.test.ts
@@ -78,6 +78,23 @@ describe('findBreakpoints', () => {
     }
   })
 
+  describe('RTL scripts (Arabic)', () => {
+    it('breaks after a space, the same as any other space-delimited script', () => {
+      // "مرحبا بالعالم" — "hello world", two space-separated words. Arabic
+      // reads right to left, but findBreakpoints works on logical (storage)
+      // order, so this is exactly the space rule already covered for Latin.
+      const text = 'مرحبا بالعالم'
+      expect(phrasePoints(text)).toEqual([text.indexOf(' ') + 1])
+    })
+
+    it('offers no fallback break inside a single unspaced word', () => {
+      // Arabic uses spaces between words, unlike CJK — so a single word
+      // with no space gets no break at all, the same as a Latin one.
+      const priorities = findBreakpoints('اختبار')
+      expect(priorities.every((p) => p === BreakPriority.none)).toBe(true)
+    })
+  })
+
   describe('kinsoku', () => {
     it('does not let a full stop start a line', () => {
       const priorities = findBreakpoints('です。ます')