diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index f20dd7d..3dec5d3 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -25,9 +25,11 @@ jobs:
         run: go get -t -v ./...
       - name: Go vet
         run: go vet ./...
-      - name: Run all tests
+      - name: Run spec tests
+        run: go test -v ./... -tags='norace'
+      - name: Run all tests with race detection
         timeout-minutes: 1
-        run: go test -race -covermode atomic -coverprofile=profile.cov -v ./...
+        run: go test -race -covermode atomic -coverprofile=profile.cov -v ./... -tags='!norace'
       - name: Send coverage
         uses: shogo82148/actions-goveralls@v1
         with:
diff --git a/Makefile b/Makefile
index 39119af..4651b4a 100644
--- a/Makefile
+++ b/Makefile
@@ -25,4 +25,4 @@ test: check
 	go test ./...
 
 test-race: check
-	go test -race ./...
+	go test -race ./... -tags='!norace'
diff --git a/internal/strategies/flexible_rollout_test.go b/internal/strategies/flexible_rollout_test.go
index 57f9e6b..7221968 100644
--- a/internal/strategies/flexible_rollout_test.go
+++ b/internal/strategies/flexible_rollout_test.go
@@ -1,3 +1,5 @@
+// +build norace
+
 package strategies
 
 import (
diff --git a/internal/strategies/gradual_rollout_random_test.go b/internal/strategies/gradual_rollout_random_test.go
index 7160e95..a0e9790 100644
--- a/internal/strategies/gradual_rollout_random_test.go
+++ b/internal/strategies/gradual_rollout_random_test.go
@@ -1,3 +1,5 @@
+// +build norace
+
 package strategies
 
 import (
diff --git a/internal/strategies/gradual_rollout_session_id_test.go b/internal/strategies/gradual_rollout_session_id_test.go
index 442e917..0d9ef0c 100644
--- a/internal/strategies/gradual_rollout_session_id_test.go
+++ b/internal/strategies/gradual_rollout_session_id_test.go
@@ -1,3 +1,5 @@
+// +build norace
+
 package strategies
 
 import (
diff --git a/internal/strategies/gradual_rollout_user_id_test.go b/internal/strategies/gradual_rollout_user_id_test.go
index c010b21..d14d58e 100644
--- a/internal/strategies/gradual_rollout_user_id_test.go
+++ b/internal/strategies/gradual_rollout_user_id_test.go
@@ -1,3 +1,5 @@
+// +build norace
+
 package strategies
 
 import (
diff --git a/spec_test.go b/spec_test.go
index 9f34617..3355c77 100644
--- a/spec_test.go
+++ b/spec_test.go
@@ -1,3 +1,5 @@
+// +build norace
+
 package unleash
 
 import (