diff --git a/packages/spike/src/gitea/test/helpers.ts b/packages/spike/src/gitea/test/helpers.ts
index 44805fa..098fbb0 100644
--- a/packages/spike/src/gitea/test/helpers.ts
+++ b/packages/spike/src/gitea/test/helpers.ts
@@ -228,10 +228,30 @@ export async function commentOnPR(repo: string, prNumber: number, body: string,
 }
 
 export async function mergePR(repo: string, prNumber: number, user: User) {
-  return giteaFetch(`/repos/${repo}/pulls/${prNumber}/merge`, user, {
-    method: "POST",
-    body: JSON.stringify({ Do: "merge", merge_message_field: "Test merge" }),
-  })
+  // Gitea returns 404/405 while computing mergeability after PR creation
+  const path = `/repos/${repo}/pulls/${prNumber}/merge`
+
+  for (let attempt = 0; attempt < 10; attempt++) {
+    const response = await fetch(`${giteaUrl}/api/v1${path}`, {
+      method: "POST",
+      headers: {
+        Authorization: `token ${user.token}`,
+        "Content-Type": "application/json",
+      },
+      body: JSON.stringify({ Do: "merge" }),
+    })
+
+    if (response.ok) return
+    if (response.status === 404 || response.status === 405) {
+      await Bun.sleep(1000)
+      continue
+    }
+
+    const body = await response.text().catch(() => "")
+    throw new Error(`Gitea ${response.status}: POST ${path}\n${body}`)
+  }
+
+  throw new Error(`Gitea merge failed after 10 retries for ${path}`)
 }
 
 export async function createReview(repo: string, prNumber: number, user: User, filePath: string) {
diff --git a/packages/spike/src/gitea/test/webhooks.test.ts b/packages/spike/src/gitea/test/webhooks.test.ts
index 419c4ec..6d31975 100644
--- a/packages/spike/src/gitea/test/webhooks.test.ts
+++ b/packages/spike/src/gitea/test/webhooks.test.ts
@@ -4,7 +4,6 @@ setDefaultTimeout(30_000)
 import { ensure } from "@workshop/shared/utils"
 import {
   type User,
-  type TestPR,
   setupWebhooks,
   expectPullRequestWebhook,
   expectIssueCommentWebhook,
@@ -15,6 +14,10 @@ import {
   mergePR,
 } from "./helpers"
 
+function testBranch(label: string) {
+  return `test-${crypto.randomUUID().slice(0, 8)}-${label}`
+}
+
 function getEnv(name: string): string {
   const value = process.env[name]
   ensure(value, `Missing env var: ${name}. See .env.example`)
@@ -37,20 +40,19 @@ afterAll(() => teardown())
 // --- Tests for Corey's repo (Spike opens PR, Corey comments/reviews/merges) ---
 
 describe(`${coreyRepo}`, () => {
-  let pr: TestPR
-  const branch = `test-${Date.now()}-corey`
-
   test("opening a PR sends pull_request webhook with correct author and repo", async () => {
-    pr = await expectPullRequestWebhook({ action: "opened", branch }, async (webhook) => {
-      const result = await openTestPR(coreyRepo, spike, branch)
+    const branch = testBranch("open")
+    await expectPullRequestWebhook({ action: "opened", branch }, async (webhook) => {
+      await openTestPR(coreyRepo, spike, branch)
       const payload = await webhook
       expect(payload.pull_request.user.login).toBe(spike.username)
       expect(payload.repository.full_name).toBe(coreyRepo)
-      return result
     })
   })
 
   test("commenting sends issue_comment webhook with correct user", async () => {
+    const branch = testBranch("comment")
+    const pr = await openTestPR(coreyRepo, spike, branch)
     await expectIssueCommentWebhook({ action: "created", username: corey.username, prNumber: pr.number }, async (webhook) => {
       await commentOnPR(coreyRepo, pr.number, "Looks good!", corey)
       const payload = await webhook
@@ -59,6 +61,8 @@ describe(`${coreyRepo}`, () => {
   })
 
   test("review with line comment sends pull_request_comment webhook", async () => {
+    const branch = testBranch("review")
+    const pr = await openTestPR(coreyRepo, spike, branch)
     await expectPullRequestCommentWebhook({ action: "reviewed", branch }, async (webhook) => {
       await createReview(coreyRepo, pr.number, corey, pr.filename)
       const payload = await webhook
@@ -68,6 +72,8 @@ describe(`${coreyRepo}`, () => {
   })
 
   test("merging sends pull_request closed webhook", async () => {
+    const branch = testBranch("merge")
+    const pr = await openTestPR(coreyRepo, spike, branch)
     await expectPullRequestWebhook({ action: "closed", branch }, async (webhook) => {
       await mergePR(coreyRepo, pr.number, corey)
       const payload = await webhook
@@ -79,20 +85,19 @@ describe(`${coreyRepo}`, () => {
 // --- Tests for Spike's repo (Corey opens PR, Spike comments/reviews/merges) ---
 
 describe(`${spikeRepo}`, () => {
-  let pr: TestPR
-  const branch = `test-${Date.now()}-spike`
-
   test("opening a PR sends pull_request webhook with correct author and repo", async () => {
-    pr = await expectPullRequestWebhook({ action: "opened", branch }, async (webhook) => {
-      const result = await openTestPR(spikeRepo, corey, branch)
+    const branch = testBranch("open")
+    await expectPullRequestWebhook({ action: "opened", branch }, async (webhook) => {
+      await openTestPR(spikeRepo, corey, branch)
       const payload = await webhook
       expect(payload.pull_request.user.login).toBe(corey.username)
       expect(payload.repository.full_name).toBe(spikeRepo)
-      return result
     })
   })
 
   test("commenting sends issue_comment webhook with correct user", async () => {
+    const branch = testBranch("comment")
+    const pr = await openTestPR(spikeRepo, corey, branch)
     await expectIssueCommentWebhook({ action: "created", username: spike.username, prNumber: pr.number }, async (webhook) => {
       await commentOnPR(spikeRepo, pr.number, "On it!", spike)
       const payload = await webhook
@@ -101,6 +106,8 @@ describe(`${spikeRepo}`, () => {
   })
 
   test("review with line comment sends pull_request_comment webhook", async () => {
+    const branch = testBranch("review")
+    const pr = await openTestPR(spikeRepo, corey, branch)
     await expectPullRequestCommentWebhook({ action: "reviewed", branch }, async (webhook) => {
       await createReview(spikeRepo, pr.number, spike, pr.filename)
       const payload = await webhook
@@ -110,6 +117,8 @@ describe(`${spikeRepo}`, () => {
   })
 
   test("merging sends pull_request closed webhook", async () => {
+    const branch = testBranch("merge")
+    const pr = await openTestPR(spikeRepo, corey, branch)
     await expectPullRequestWebhook({ action: "closed", branch }, async (webhook) => {
       await mergePR(spikeRepo, pr.number, spike)
       const payload = await webhook