diff --git a/e2e/CLAUDE.md b/e2e/CLAUDE.md
index fbf1e794..ebbb70f2 100644
--- a/e2e/CLAUDE.md
+++ b/e2e/CLAUDE.md
@@ -308,10 +308,15 @@ something no cheaper tier can.
   `web/` states, enforced by construction rather than by mock resetting.
   A workspace slug is unique server-side, so two tests sharing one would
   fail on the second, exactly as two sharing an email would.
-- **Workers are capped at four.** Every test's setup is three
-  cross-service round trips against one core and one postgres; past a
-  few workers the setup starts timing out, which reads as flaky tests
-  when it is only load.
+- **Workers are capped at four locally and two on CI.** Every test's
+  setup is several cross-service round trips against one core and one
+  postgres; past a few workers the setup starts timing out, which reads
+  as flaky tests when it is only load — and a private-repo CI runner has
+  two vCPUs for the stack and the browsers together. For the same
+  reason the test budget is 60s (a 7s local test is a 40s test on that
+  runner), and the collaboration tests are marked slow, tripling theirs:
+  each one runs two signups, two verifications, an invitation and its
+  acceptance before the first assertion.
 - **No test depends on another's state or on execution order**, and no
   test cleans up after itself: the stack's database is thrown away
   wholesale, which is why it carries no volumes.
diff --git a/e2e/playwright.config.ts b/e2e/playwright.config.ts
index 2b38be6f..17d893cf 100644
--- a/e2e/playwright.config.ts
+++ b/e2e/playwright.config.ts
@@ -8,7 +8,14 @@ export default defineConfig({
 	// workspace before it starts, and the stack answers all of them from
 	// one core and one postgres. Past a few workers the setup itself
 	// starts timing out, which reads as flaky tests when it is only load.
-	workers: 4,
+	// CI gets fewer still: a private-repo runner has two vCPUs for the
+	// whole stack and the browsers together.
+	workers: process.env.CI ? 2 : 4,
+	// the default 30s budget contradicts the suite's own waits — a login
+	// redirect is allowed 15s and an invite acceptance 30s, because they
+	// are cross-service chains that stretch under load. CI runs the whole
+	// stack on two cores, where a test that takes 7s locally takes 40.
+	timeout: 60_000,
 	forbidOnly: !!process.env.CI,
 	retries: process.env.CI ? 2 : 0,
 	// github gives inline annotations on the PR; html is what the
diff --git a/e2e/tests/collaboration.test.ts b/e2e/tests/collaboration.test.ts
index 41f7671b..628de8f0 100644
--- a/e2e/tests/collaboration.test.ts
+++ b/e2e/tests/collaboration.test.ts
@@ -14,6 +14,13 @@ import { visit } from "../helpers/page"
 import { signUpWithWorkspace } from "../helpers/workspace"
 
 test.describe("collaboration", () => {
+	// the heaviest setup in the suite: every test runs two signups, two
+	// email verifications, an invitation and its acceptance before the
+	// first assertion. slow() triples the budget for exactly these tests.
+	test.beforeEach(() => {
+		test.slow()
+	})
+
 	test("shows text typed by one user to the other", async ({
 		page,
 		request,