diff --git a/repos/base/include/base/heap.h b/repos/base/include/base/heap.h
index 54b1392bd3..feab513381 100644
--- a/repos/base/include/base/heap.h
+++ b/repos/base/include/base/heap.h
@@ -19,7 +19,7 @@
 #include <base/ram_allocator.h>
 #include <region_map/region_map.h>
 #include <base/allocator_avl.h>
-#include <base/lock.h>
+#include <base/mutex.h>
 
 namespace Genode {
 
@@ -89,7 +89,7 @@ class Genode::Heap : public Allocator
 					ram_alloc = ram, region_map = rm; }
 		};
 
-		Lock                   mutable _lock { };
+		Mutex                  mutable _mutex { };
 		Reconstructible<Allocator_avl> _alloc;        /* local allocator    */
 		Dataspace_pool                 _ds_pool;      /* list of dataspaces */
 		size_t                         _quota_limit { 0 };
@@ -157,7 +157,7 @@ class Genode::Heap : public Allocator
 		template <typename FN>
 		void for_each_region(FN const &fn) const
 		{
-			Lock::Guard guard(_lock);
+			Mutex::Guard guard(_mutex);
 			for (Dataspace const *ds = _ds_pool.first(); ds; ds = ds->next())
 				fn(ds->local_addr, ds->size);
 		}
@@ -198,7 +198,7 @@ class Genode::Sliced_heap : public Allocator
 		Region_map     &_region_map;    /* region map of the address space */
 		size_t          _consumed = 0;  /* number of allocated bytes       */
 		List<Block>     _blocks { };    /* list of allocated blocks        */
-		Lock            _lock   { };    /* serialize allocations           */
+		Mutex           _mutex  { };    /* serialize allocations           */
 
 	public:
 
diff --git a/repos/base/src/lib/base/heap.cc b/repos/base/src/lib/base/heap.cc
index 11bd075394..a068576ec5 100644
--- a/repos/base/src/lib/base/heap.cc
+++ b/repos/base/src/lib/base/heap.cc
@@ -224,7 +224,7 @@ bool Heap::alloc(size_t size, void **out_addr)
 		error("attempt to allocate zero-size block from heap");
 
 	/* serialize access of heap functions */
-	Lock::Guard lock_guard(_lock);
+	Mutex::Guard guard(_mutex);
 
 	/* check requested allocation against quota limit */
 	if (size + _quota_used > _quota_limit)
@@ -237,7 +237,7 @@ bool Heap::alloc(size_t size, void **out_addr)
 void Heap::free(void *addr, size_t)
 {
 	/* serialize access of heap functions */
-	Lock::Guard lock_guard(_lock);
+	Mutex::Guard guard(_mutex);
 
 	/* try to find the size in our local allocator */
 	size_t const size = _alloc->size_at(addr);
diff --git a/repos/base/src/lib/base/sliced_heap.cc b/repos/base/src/lib/base/sliced_heap.cc
index 43483a6005..274365e942 100644
--- a/repos/base/src/lib/base/sliced_heap.cc
+++ b/repos/base/src/lib/base/sliced_heap.cc
@@ -65,7 +65,7 @@ bool Sliced_heap::alloc(size_t size, void **out_addr)
 	}
 
 	/* serialize access to block list */
-	Lock::Guard lock_guard(_lock);
+	Mutex::Guard guard(_mutex);
 
 	construct_at<Block>(block, ds_cap, size);
 
@@ -85,7 +85,7 @@ void Sliced_heap::free(void *addr, size_t)
 	void *local_addr = nullptr;
 	{
 		/* serialize access to block list */
-		Lock::Guard lock_guard(_lock);
+		Mutex::Guard guard(_mutex);
 
 		/*
 		 * The 'addr' argument points to the payload. We use pointer