diff --git a/context.go b/context.go
index 3c55c5f..a7f7d85 100644
--- a/context.go
+++ b/context.go
@@ -19,43 +19,45 @@ var (
 // Set stores a value for a given key in a given request.
 func Set(r *http.Request, key, val interface{}) {
 	mutex.Lock()
-	defer mutex.Unlock()
 	if data[r] == nil {
 		data[r] = make(map[interface{}]interface{})
 		datat[r] = time.Now().Unix()
 	}
 	data[r][key] = val
+	mutex.Unlock()
 }
 
 // Get returns a value stored for a given key in a given request.
 func Get(r *http.Request, key interface{}) interface{} {
 	mutex.RLock()
-	defer mutex.RUnlock()
 	if data[r] != nil {
+		mutex.RUnlock()
 		return data[r][key]
 	}
+	mutex.RUnlock()
 	return nil
 }
 
 // GetOk returns stored value and presence state like multi-value return of map access.
 func GetOk(r *http.Request, key interface{}) (interface{}, bool) {
 	mutex.RLock()
-	defer mutex.RUnlock()
 	if _, ok := data[r]; ok {
 		value, ok := data[r][key]
+		mutex.RUnlock()
 		return value, ok
 	}
+	mutex.RUnlock()
 	return nil, false
 }
 
 // GetAll returns all stored values for the request as a map. Nil is returned for invalid requests.
 func GetAll(r *http.Request) map[interface{}]interface{} {
 	mutex.RLock()
-	defer mutex.RUnlock()
-
 	if context, ok := data[r]; ok {
+		mutex.RUnlock()
 		return context
 	}
+	mutex.RUnlock()
 	return nil
 }
 
@@ -63,19 +65,18 @@ func GetAll(r *http.Request) map[interface{}]interface{} {
 // ok if the request was never registered.
 func GetAllOk(r *http.Request) (map[interface{}]interface{}, bool) {
 	mutex.RLock()
-	defer mutex.RUnlock()
-
 	context, ok := data[r]
+	mutex.RUnlock()
 	return context, ok
 }
 
 // Delete removes a value stored for a given key in a given request.
 func Delete(r *http.Request, key interface{}) {
 	mutex.Lock()
-	defer mutex.Unlock()
 	if data[r] != nil {
 		delete(data[r], key)
 	}
+	mutex.Unlock()
 }
 
 // Clear removes all values stored for a given request.
@@ -84,8 +85,8 @@ func Delete(r *http.Request, key interface{}) {
 // variables at the end of a request lifetime. See ClearHandler().
 func Clear(r *http.Request) {
 	mutex.Lock()
-	defer mutex.Unlock()
 	clear(r)
+	mutex.Unlock()
 }
 
 // clear is Clear without the lock.
@@ -105,7 +106,6 @@ func clear(r *http.Request) {
 // periodically until the problem is fixed.
 func Purge(maxAge int) int {
 	mutex.Lock()
-	defer mutex.Unlock()
 	count := 0
 	if maxAge <= 0 {
 		count = len(data)
@@ -120,6 +120,7 @@ func Purge(maxAge int) int {
 			}
 		}
 	}
+	mutex.Unlock()
 	return count
 }