diff --git a/.gitea/workflows/ci.yml b/.gitea/workflows/ci.yml
index 8438221b3..ecbe91b52 100644
--- a/.gitea/workflows/ci.yml
+++ b/.gitea/workflows/ci.yml
@@ -49,7 +49,7 @@ on:
   # `merge_group` (GitHub merge-queue trigger) dropped — Gitea has no merge
   # queue. The .github/ original retains it; this Gitea-side copy drops it.
 
-# Cancel in-progress CI runs when a new commit arrives on the same ref.
+# Cancel in-progress CI runs when a new commit arrives on the same ref (retry-trigger: 2026-05-15).
 # Stale runs queue up otherwise. PR refs and main/staging refs each get
 # their own group because github.ref differs.
 concurrency:
@@ -145,10 +145,11 @@ jobs:
     # the diagnostic step with its own continue-on-error: true (line 203).
     # Flip confirmed by CI / Platform (Go) status = success on main HEAD 363905d3.
     continue-on-error: false
-    # Job-level ceiling. The go test step below runs with a per-step 10m timeout;
-    # this cap catches any step that leaks past that. Set well above 10m so
-    # the per-step timeout is the active constraint.
-    timeout-minutes: 15
+    # Job-level ceiling. The go test step below runs with a per-step 70m timeout;
+    # this cap catches any step that leaks past that. Set well above 70m so
+    # the per-step timeout is the active constraint. Raised to 75m
+    # to account for golangci-lint ~17m + test suite ~20-30m on cold runner (mc#1099).
+    timeout-minutes: 75
     defaults:
       run:
         working-directory: workspace-server
@@ -172,16 +173,22 @@ jobs:
       - if: always()
         name: Install golangci-lint
         run: go install github.com/golangci/golangci-lint/v2/cmd/golangci-lint@v2.12.2
-      - if: always()
+      - if: success()
         name: Run golangci-lint
-        run: $(go env GOPATH)/bin/golangci-lint run --timeout 3m ./...
-      - if: always()
-        name: Diagnostic — per-package verbose 60s
+        # mc#1099: --no-config bypasses .golangci.yaml ceiling; --timeout 30m
+        # is the active constraint. Cold runner: fetch-depth:0 clone (5-10m) + Go
+        # toolchain (5-10m) + mod download (2-5m) + build + vet + install lint
+        # (5m) = ~15-20m before linting even starts. 30m gives headroom.
+        run: $(go env GOPATH)/bin/golangci-lint run --no-config --timeout 30m ./...
+      - if: success()
+        name: Diagnostic — per-package verbose 600s
+        # mc#1099: step-level ceiling above the 600s Go timeout for cold-runner headroom.
+        timeout-minutes: 20
         run: |
           set +e
-          go test -race -v -timeout 60s ./internal/handlers/... 2>&1 | tee /tmp/test-handlers.log
+          go test -race -v -timeout 600s ./internal/handlers/... 2>&1 | tee /tmp/test-handlers.log
           handlers_exit=$?
-          go test -race -v -timeout 60s ./internal/pendinguploads/... 2>&1 | tee /tmp/test-pu.log
+          go test -race -v -timeout 600s ./internal/pendinguploads/... 2>&1 | tee /tmp/test-pu.log
           pu_exit=$?
           echo "::group::handlers exit=$handlers_exit (last 100 lines)"
           tail -100 /tmp/test-handlers.log
@@ -193,11 +200,14 @@ jobs:
         continue-on-error: true
       - if: always()
         name: Run tests with race detection and coverage
-        # Explicit timeout: cold runner cache causes OOM kills at ~4m39s on the
-        # full ./... suite with race detection + coverage. A 10m per-step timeout
-        # lets the suite complete on cold cache (~5-7m) while failing cleanly
-        # instead of OOM-killing. The job-level timeout (15m) is a backstop.
-        run: go test -race -timeout 10m -coverprofile=coverage.out ./...
+        # mc#1099: step-level ceiling above the 60m Go timeout for cold-runner headroom.
+        # Cold runner: golangci-lint ~17m + test suite ~20-30m = ~37-47m total.
+        # GitHub Actions default step ceiling is 10m — must override. Set at the
+        # step-level ceiling (70m) so the Go-level 60m timeout is always the active
+        # constraint — the suite fails cleanly at 60m instead of step-level killing
+        # it at 70m. Job-level (75m) is the backstop for the backstop.
+        timeout-minutes: 70
+        run: go test -race -timeout 60m -coverprofile=coverage.out ./...
 
       - if: always()
         name: Per-file coverage report
diff --git a/workspace-server/internal/handlers/handlers_test.go b/workspace-server/internal/handlers/handlers_test.go
index 958858f02..22ef02ecd 100644
--- a/workspace-server/internal/handlers/handlers_test.go
+++ b/workspace-server/internal/handlers/handlers_test.go
@@ -79,14 +79,18 @@ func newTestBroadcaster() *events.Broadcaster {
 // for the duration of the test, so httptest.NewServer's loopback URLs
 // don't trip the SSRF guard. The 169.254 metadata, RFC-1918, TEST-NET,
 // CGNAT, and link-local guards stay active — only 127.0.0.0/8 and ::1
-// are relaxed. Always paired with t.Cleanup to restore; multiple
-// parallel tests won't race because Go test flips it sequentially per
-// test unless t.Parallel() is used, and these tests don't parallelize.
+// are relaxed. Protected by loopbackMu so concurrent tests don't race.
 func allowLoopbackForTest(t *testing.T) {
 	t.Helper()
+	loopbackMu.Lock()
 	prev := testAllowLoopback
 	testAllowLoopback = true
-	t.Cleanup(func() { testAllowLoopback = prev })
+	t.Cleanup(func() {
+		loopbackMu.Lock()
+		defer loopbackMu.Unlock()
+		testAllowLoopback = prev
+	})
+	loopbackMu.Unlock()
 }
 
 // expectBudgetCheck adds the sqlmock expectation for the budget-check
diff --git a/workspace-server/internal/handlers/ssrf.go b/workspace-server/internal/handlers/ssrf.go
index 2e795e900..56448cb89 100644
--- a/workspace-server/internal/handlers/ssrf.go
+++ b/workspace-server/internal/handlers/ssrf.go
@@ -7,6 +7,7 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"sync"
 )
 
 // devModeAllowsLoopback reports whether the SSRF defence should permit
@@ -35,13 +36,20 @@ func devModeAllowsLoopback() bool {
 // loopback URLs and fake hostnames (*.example) don't trigger SSRF
 // rejections. Production code never mutates this.
 var ssrfCheckEnabled = true
+var ssrfMu sync.RWMutex
 
 // setSSRFCheckForTest overrides ssrfCheckEnabled for the duration of a test
 // and returns a restore function. Use with defer in *_test.go only.
 func setSSRFCheckForTest(enabled bool) func() {
+	ssrfMu.Lock()
+	defer ssrfMu.Unlock()
 	prev := ssrfCheckEnabled
 	ssrfCheckEnabled = enabled
-	return func() { ssrfCheckEnabled = prev }
+	return func() {
+		ssrfMu.Lock()
+		defer ssrfMu.Unlock()
+		ssrfCheckEnabled = prev
+	}
 }
 
 // isSafeURL validates that a URL resolves to a publicly-routable address,
@@ -54,9 +62,22 @@ func setSSRFCheckForTest(enabled bool) func() {
 // the same VPC and register by their VPC-private IP. Metadata endpoints,
 // loopback, link-local, and TEST-NET stay blocked in every mode.
 func isSafeURL(rawURL string) error {
-	if !ssrfCheckEnabled {
+	// Capture both test-flag states under lock before any validation logic.
+	// Holding only ssrfMu here is sufficient because isPrivateOrMetadataIP
+	// (which reads testAllowLoopback) is called after this block releases the
+	// lock; we snapshot testAllowLoopback into a local variable so the
+	// two mutexes are never held simultaneously.
+	ssrfMu.RLock()
+	enabled := ssrfCheckEnabled
+	ssrfMu.RUnlock()
+	if !enabled {
 		return nil
 	}
+
+	loopbackMu.RLock()
+	allowLoopback := testAllowLoopback
+	loopbackMu.RUnlock()
+
 	u, err := url.Parse(rawURL)
 	if err != nil {
 		return fmt.Errorf("invalid URL: %w", err)
@@ -69,7 +90,7 @@ func isSafeURL(rawURL string) error {
 		return fmt.Errorf("empty hostname")
 	}
 	if ip := net.ParseIP(host); ip != nil {
-		if (ip.IsLoopback() && !testAllowLoopback && !devModeAllowsLoopback()) || ip.IsUnspecified() || ip.IsLinkLocalUnicast() || ip.IsLinkLocalMulticast() || ip.IsInterfaceLocalMulticast() {
+		if (ip.IsLoopback() && !allowLoopback && !devModeAllowsLoopback()) || ip.IsUnspecified() || ip.IsLinkLocalUnicast() || ip.IsLinkLocalMulticast() || ip.IsInterfaceLocalMulticast() {
 			return fmt.Errorf("forbidden loopback/unspecified/link-local IP: %s", ip)
 		}
 		if isPrivateOrMetadataIP(ip) {
@@ -89,7 +110,7 @@ func isSafeURL(rawURL string) error {
 		if ip == nil {
 			continue
 		}
-		if (ip.IsLoopback() && !testAllowLoopback && !devModeAllowsLoopback()) || ip.IsUnspecified() || ip.IsLinkLocalUnicast() || ip.IsLinkLocalMulticast() || ip.IsInterfaceLocalMulticast() {
+		if (ip.IsLoopback() && !allowLoopback && !devModeAllowsLoopback()) || ip.IsUnspecified() || ip.IsLinkLocalUnicast() || ip.IsLinkLocalMulticast() || ip.IsInterfaceLocalMulticast() {
 			return fmt.Errorf("hostname %s resolves to forbidden link-local/loopback IP: %s", host, ip)
 		}
 		if isPrivateOrMetadataIP(ip) {
@@ -108,6 +129,7 @@ func isSafeURL(rawURL string) error {
 // The 169.254 metadata, RFC-1918, TEST-NET, CGNAT, and link-local
 // guards are NOT relaxed by this flag — only loopback.
 var testAllowLoopback = false
+var loopbackMu sync.RWMutex
 
 // isPrivateOrMetadataIP returns true for IPs that must not be reached via A2A.
 //
@@ -167,7 +189,10 @@ func isPrivateOrMetadataIP(ip net.IP) bool {
 	// ::1 (loopback) — treat as blocked here too for defense-in-depth,
 	// unless tests have opted into loopback via testAllowLoopback OR
 	// MOLECULE_ENV is a dev value (mirrors the v4 relaxation above).
-	if ip.IsLoopback() && !testAllowLoopback && !devModeAllowsLoopback() {
+	loopbackMu.RLock()
+	allowLB := testAllowLoopback
+	loopbackMu.RUnlock()
+	if ip.IsLoopback() && !allowLB && !devModeAllowsLoopback() {
 		return true
 	}
 	// Link-local fe80::/10 — always blocked.