diff --git a/lib/khmer.hh b/lib/khmer.hh
index f43a894117..be97ac5001 100644
--- a/lib/khmer.hh
+++ b/lib/khmer.hh
@@ -122,7 +122,7 @@ typedef unsigned short int BoundedCounterType;
 
 // A single-byte type.
 typedef unsigned char Byte;
-typedef std::atomic<uint8_t> AtomicByte;
+using AtomicByte = std::atomic<uint8_t>;
 
 
 typedef void (*CallbackFn)(const char * info, void * callback_data,
diff --git a/lib/storage.hh b/lib/storage.hh
index 52ed32112f..6171563bb6 100644
--- a/lib/storage.hh
+++ b/lib/storage.hh
@@ -38,10 +38,6 @@ Contact: khmer-project@idyll.org
 #ifndef STORAGE_HH
 #define STORAGE_HH
 
-#include <cassert>
-#include <array>
-#include <mutex>
-using MuxGuard = std::lock_guard<std::mutex>;
 
 namespace khmer
 {
@@ -262,8 +258,6 @@ public:
     NibbleStorage(std::vector<uint64_t>& tablesizes) :
         _tablesizes{tablesizes}, _occupied_bins{0}, _n_unique_kmers{0}
     {
-        // to allow more than 32 tables increase the size of mutex pool
-        assert(_n_tables <= 32);
         _allocate_counters();
     }
 
diff --git a/tests/test_countgraph.py b/tests/test_countgraph.py
index 4c70e5e849..9349ec834f 100644
--- a/tests/test_countgraph.py
+++ b/tests/test_countgraph.py
@@ -212,9 +212,6 @@ def test_get_raw_tables_smallcountgraph():
     # smallcountgraphs store individual counts packed into a byte, the raw tables
     # probably do not give users what they expect (something that can be
     # given to numpy.frombuffer)
-
-    # for the same number of entries a SmallCountgraph uses ~half the memory
-    # of a normal Countgraph
     ht = khmer.SmallCountgraph(20, 1e5, 4)
     assert not hasattr(ht, 'get_raw_tables')