diff --git a/creational/builder.md b/creational/builder.md
index e19179e..bab13fa 100644
--- a/creational/builder.md
+++ b/creational/builder.md
@@ -36,7 +36,7 @@ const (
 )
 
 type Builder interface {
-    Color(Color) Builder
+    Paint(Color) Builder
     Wheels(Wheels) Builder
     TopSpeed(Speed) Builder
     Build() Interface
diff --git a/synchronization/semaphore.md b/synchronization/semaphore.md
index 85c7109..6fa2090 100644
--- a/synchronization/semaphore.md
+++ b/synchronization/semaphore.md
@@ -7,7 +7,7 @@ A semaphore is a synchronization pattern/primitive that imposes mutual exclusion
 package semaphore
 
 var (
-	ErrNoTickets      = errors.New("semaphore: could not aquire semaphore")
+	ErrNoTickets      = errors.New("semaphore: could not acquire semaphore")
 	ErrIllegalRelease = errors.New("semaphore: can't release the semaphore without acquiring it first")
 )
 
@@ -38,8 +38,6 @@ func (s *implementation) Release() error {
 	case <-time.After(s.timeout):
 		return ErrIllegalRelease
 	}
-
-	return nil
 }
 
 func New(tickets int, timeout time.Duration) Interface {