diff --git a/src/pow.h b/src/pow.h
index 28bc894..78fc665 100644
--- a/src/pow.h
+++ b/src/pow.h
@@ -1,8 +1,8 @@
 #ifndef BITMESSAGE_POW_H
 #define BITMESSAGE_POW_H
 
-#define MAX_POOL_SIZE 1024
-#define HASH_SIZE 64
+static const int MAX_POOL_SIZE = 1024;
+static const int HASH_SIZE = 64;
 
 int pow(size_t pool_size,
         uint64_t target,
diff --git a/src/worker.cc b/src/worker.cc
index d159f92..01bfb26 100644
--- a/src/worker.cc
+++ b/src/worker.cc
@@ -2,8 +2,6 @@
 #include <nan.h>
 #include "./pow.h"
 
-#define MAX_SAFE_INTEGER 9007199254740991
-
 using node::Buffer;
 using v8::Handle;
 using v8::Local;
@@ -14,6 +12,8 @@ using v8::Object;
 using v8::String;
 using v8::Integer;
 
+static const uint64_t MAX_SAFE_INTEGER = 9007199254740991ULL;
+
 class PowWorker : public NanAsyncWorker {
  public:
   PowWorker(NanCallback* callback,
@@ -77,13 +77,12 @@ NAN_METHOD(PowAsync) {
 
   size_t pool_size = args[0]->Uint32Value();
   uint64_t target = args[1]->IntegerValue();
-  size_t length = Buffer::Length(args[2]->ToObject());
   char* buf = Buffer::Data(args[2]->ToObject());
-  if (
-      pool_size < 1 ||
+  size_t length = Buffer::Length(args[2]->ToObject());
+  if (pool_size < 1 ||
       pool_size > MAX_POOL_SIZE ||
-      length != HASH_SIZE ||
-      buf == NULL) {
+      buf == NULL ||
+      length != HASH_SIZE) {
     return NanThrowError("Bad input");
   }