diff --git a/configure.ac b/configure.ac
index f5bc1e312..2c918218b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -350,8 +350,8 @@ if test x$use_lcov = xyes; then
     [AC_MSG_ERROR("lcov testing requested but --coverage flag does not work")])
 fi
 
-dnl Require little endian
-AC_C_BIGENDIAN([AC_MSG_ERROR("Big Endian not supported")])
+dnl Check for endianness
+AC_C_BIGENDIAN
 
 dnl Check for pthread compile/link requirements
 AX_PTHREAD
@@ -438,17 +438,22 @@ if test x$TARGET_OS = xdarwin; then
   AX_CHECK_LINK_FLAG([[-Wl,-dead_strip]], [LDFLAGS="$LDFLAGS -Wl,-dead_strip"])
 fi
 
-AC_CHECK_HEADERS([endian.h stdio.h stdlib.h unistd.h strings.h sys/types.h sys/stat.h sys/select.h sys/prctl.h])
+AC_CHECK_HEADERS([endian.h byteswap.h stdio.h stdlib.h unistd.h strings.h sys/types.h sys/stat.h sys/select.h sys/prctl.h])
 AC_SEARCH_LIBS([getaddrinfo_a], [anl], [AC_DEFINE(HAVE_GETADDRINFO_A, 1, [Define this symbol if you have getaddrinfo_a])])
 AC_SEARCH_LIBS([inet_pton], [nsl resolv], [AC_DEFINE(HAVE_INET_PTON, 1, [Define this symbol if you have inet_pton])])
 
 AC_CHECK_DECLS([strnlen])
 
-AC_CHECK_DECLS([le32toh, le64toh, htole32, htole64, be32toh, be64toh, htobe32, htobe64],,,
+AC_CHECK_DECLS([le16toh, le32toh, le64toh, htole16, htole32, htole64, be16toh, be32toh, be64toh, htobe16, htobe32, htobe64],,,
 		[#if HAVE_ENDIAN_H
                  #include <endian.h>
                  #endif])
 
+AC_CHECK_DECLS([bswap_16, bswap_32, bswap_64],,,
+		[#if HAVE_BYTESWAP_H
+                 #include <byteswap.h>
+                 #endif])
+
 dnl Check for MSG_NOSIGNAL
 AC_MSG_CHECKING(for MSG_NOSIGNAL)
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <sys/socket.h>]],
diff --git a/src/Makefile.am b/src/Makefile.am
index e1d467ff8..da65efa71 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -141,6 +141,8 @@ BITCOIN_CORE_H = \
   walletdb.h \
   wallet.h \
   wallet_ismine.h \
+  compat/byteswap.h \
+  compat/endian.h \
   compat/sanity.h
 
 JSON_H = \
diff --git a/src/arith_uint256.cpp b/src/arith_uint256.cpp
index 1243823da..2e6136357 100644
--- a/src/arith_uint256.cpp
+++ b/src/arith_uint256.cpp
@@ -7,6 +7,7 @@
 
 #include "uint256.h"
 #include "utilstrencodings.h"
+#include "crypto/common.h"
 
 #include <stdio.h>
 #include <string.h>
@@ -246,14 +247,14 @@ uint32_t arith_uint256::GetCompact(bool fNegative) const
 uint256 ArithToUint256(const arith_uint256 &a)
 {
     uint256 b;
-    // TODO: needs bswap32 on big-endian
-    memcpy(b.begin(), a.pn, a.size());
+    for(int x=0; x<a.WIDTH; ++x)
+        WriteLE32(b.begin() + x*4, a.pn[x]);
     return b;
 }
 arith_uint256 UintToArith256(const uint256 &a)
 {
     arith_uint256 b;
-    // TODO: needs bswap32 on big-endian
-    memcpy(b.pn, a.begin(), a.size());
+    for(int x=0; x<b.WIDTH; ++x)
+        b.pn[x] = ReadLE32(a.begin() + x*4);
     return b;
 }
diff --git a/src/compat/byteswap.h b/src/compat/byteswap.h
new file mode 100644
index 000000000..899220bdc
--- /dev/null
+++ b/src/compat/byteswap.h
@@ -0,0 +1,47 @@
+// Copyright (c) 2014 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_COMPAT_BYTESWAP_H
+#define BITCOIN_COMPAT_BYTESWAP_H
+
+#if defined(HAVE_CONFIG_H)
+#include "config/bitcoin-config.h"
+#endif
+
+#include <stdint.h>
+
+#if defined(HAVE_BYTESWAP_H)
+#include <byteswap.h>
+#endif
+
+#if HAVE_DECL_BSWAP_16 == 0
+inline uint16_t bswap_16(uint16_t x)
+{
+    return (x >> 8) | ((x & 0x00ff) << 8);
+}
+#endif // HAVE_DECL_BSWAP16
+
+#if HAVE_DECL_BSWAP_32 == 0
+inline uint32_t bswap_32(uint32_t x)
+{
+    return (((x & 0xff000000U) >> 24) | ((x & 0x00ff0000U) >>  8) |
+            ((x & 0x0000ff00U) <<  8) | ((x & 0x000000ffU) << 24));
+}
+#endif // HAVE_DECL_BSWAP32
+
+#if HAVE_DECL_BSWAP_64 == 0
+inline uint64_t bswap_64(uint64_t x)
+{
+     return (((x & 0xff00000000000000ull) >> 56)
+          | ((x & 0x00ff000000000000ull) >> 40)
+          | ((x & 0x0000ff0000000000ull) >> 24)
+          | ((x & 0x000000ff00000000ull) >> 8)
+          | ((x & 0x00000000ff000000ull) << 8)
+          | ((x & 0x0000000000ff0000ull) << 24)
+          | ((x & 0x000000000000ff00ull) << 40)
+          | ((x & 0x00000000000000ffull) << 56));
+}
+#endif // HAVE_DECL_BSWAP64
+
+#endif // BITCOIN_COMPAT_BYTESWAP_H
diff --git a/src/compat/endian.h b/src/compat/endian.h
new file mode 100644
index 000000000..4d041d655
--- /dev/null
+++ b/src/compat/endian.h
@@ -0,0 +1,194 @@
+// Copyright (c) 2014 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_COMPAT_ENDIAN_H
+#define BITCOIN_COMPAT_ENDIAN_H
+
+#if defined(HAVE_CONFIG_H)
+#include "config/bitcoin-config.h"
+#endif
+
+#include <stdint.h>
+
+#include "compat/byteswap.h"
+
+#if defined(HAVE_ENDIAN_H)
+#include <endian.h>
+#endif
+
+#if defined(WORDS_BIGENDIAN)
+
+#if HAVE_DECL_HTOBE16 == 0
+inline uint16_t htobe16(uint16_t host_16bits)
+{
+    return host_16bits;
+}
+#endif // HAVE_DECL_HTOBE16
+
+#if HAVE_DECL_HTOLE16 == 0
+inline uint16_t htole16(uint16_t host_16bits)
+{
+    return bswap_16(host_16bits);
+}
+#endif // HAVE_DECL_HTOLE16
+
+#if HAVE_DECL_BE16TOH == 0
+inline uint16_t be16toh(uint16_t big_endian_16bits)
+{
+    return big_endian_16bits;
+}
+#endif // HAVE_DECL_BE16TOH
+
+#if HAVE_DECL_LE16TOH == 0
+inline uint16_t le16toh(uint16_t little_endian_16bits)
+{
+    return bswap_16(little_endian_16bits);
+}
+#endif // HAVE_DECL_LE16TOH
+
+#if HAVE_DECL_HTOBE32 == 0
+inline uint32_t htobe32(uint32_t host_32bits)
+{
+    return host_32bits;
+}
+#endif // HAVE_DECL_HTOBE32
+
+#if HAVE_DECL_HTOLE32 == 0
+inline uint32_t htole32(uint32_t host_32bits)
+{
+    return bswap_32(host_32bits);
+}
+#endif // HAVE_DECL_HTOLE32
+
+#if HAVE_DECL_BE32TOH == 0
+inline uint32_t be32toh(uint32_t big_endian_32bits)
+{
+    return big_endian_32bits;
+}
+#endif // HAVE_DECL_BE32TOH
+
+#if HAVE_DECL_LE32TOH == 0
+inline uint32_t le32toh(uint32_t little_endian_32bits)
+{
+    return bswap_32(little_endian_32bits);
+}
+#endif // HAVE_DECL_LE32TOH
+
+#if HAVE_DECL_HTOBE64 == 0
+inline uint64_t htobe64(uint64_t host_64bits)
+{
+    return host_64bits;
+}
+#endif // HAVE_DECL_HTOBE64
+
+#if HAVE_DECL_HTOLE64 == 0
+inline uint64_t htole64(uint64_t host_64bits)
+{
+    return bswap_64(host_64bits);
+}
+#endif // HAVE_DECL_HTOLE64
+
+#if HAVE_DECL_BE64TOH == 0
+inline uint64_t be64toh(uint64_t big_endian_64bits)
+{
+    return big_endian_64bits;
+}
+#endif // HAVE_DECL_BE64TOH
+
+#if HAVE_DECL_LE64TOH == 0
+inline uint64_t le64toh(uint64_t little_endian_64bits)
+{
+    return bswap_64(little_endian_64bits);
+}
+#endif // HAVE_DECL_LE64TOH
+
+#else // WORDS_BIGENDIAN
+
+#if HAVE_DECL_HTOBE16 == 0
+inline uint16_t htobe16(uint16_t host_16bits)
+{
+    return bswap_16(host_16bits);
+}
+#endif // HAVE_DECL_HTOBE16
+
+#if HAVE_DECL_HTOLE16 == 0
+inline uint16_t htole16(uint16_t host_16bits)
+{
+    return host_16bits;
+}
+#endif // HAVE_DECL_HTOLE16
+
+#if HAVE_DECL_BE16TOH == 0
+inline uint16_t be16toh(uint16_t big_endian_16bits)
+{
+    return bswap_16(big_endian_16bits);
+}
+#endif // HAVE_DECL_BE16TOH
+
+#if HAVE_DECL_LE16TOH == 0
+inline uint16_t le16toh(uint16_t little_endian_16bits)
+{
+    return little_endian_16bits;
+}
+#endif // HAVE_DECL_LE16TOH
+
+#if HAVE_DECL_HTOBE32 == 0
+inline uint32_t htobe32(uint32_t host_32bits)
+{
+    return bswap_32(host_32bits);
+}
+#endif // HAVE_DECL_HTOBE32
+
+#if HAVE_DECL_HTOLE32 == 0
+inline uint32_t htole32(uint32_t host_32bits)
+{
+    return host_32bits;
+}
+#endif // HAVE_DECL_HTOLE32
+
+#if HAVE_DECL_BE32TOH == 0
+inline uint32_t be32toh(uint32_t big_endian_32bits)
+{
+    return bswap_32(big_endian_32bits);
+}
+#endif // HAVE_DECL_BE32TOH
+
+#if HAVE_DECL_LE32TOH == 0
+inline uint32_t le32toh(uint32_t little_endian_32bits)
+{
+    return little_endian_32bits;
+}
+#endif // HAVE_DECL_LE32TOH
+
+#if HAVE_DECL_HTOBE64 == 0
+inline uint64_t htobe64(uint64_t host_64bits)
+{
+    return bswap_64(host_64bits);
+}
+#endif // HAVE_DECL_HTOBE64
+
+#if HAVE_DECL_HTOLE64 == 0
+inline uint64_t htole64(uint64_t host_64bits)
+{
+    return host_64bits;
+}
+#endif // HAVE_DECL_HTOLE64
+
+#if HAVE_DECL_BE64TOH == 0
+inline uint64_t be64toh(uint64_t big_endian_64bits)
+{
+    return bswap_64(big_endian_64bits);
+}
+#endif // HAVE_DECL_BE64TOH
+
+#if HAVE_DECL_LE64TOH == 0
+inline uint64_t le64toh(uint64_t little_endian_64bits)
+{
+    return little_endian_64bits;
+}
+#endif // HAVE_DECL_LE64TOH
+
+#endif // WORDS_BIGENDIAN
+
+#endif // BITCOIN_COMPAT_ENDIAN_H
diff --git a/src/crypto/common.h b/src/crypto/common.h
index 8b04b1f72..580c72f5a 100644
--- a/src/crypto/common.h
+++ b/src/crypto/common.h
@@ -11,110 +11,56 @@
 
 #include <stdint.h>
 
-#if defined(HAVE_ENDIAN_H)
-#include <endian.h>
-#endif
+#include "compat/endian.h"
+
+uint16_t static inline ReadLE16(const unsigned char* ptr)
+{
+    return le16toh(*((uint16_t*)ptr));
+}
 
 uint32_t static inline ReadLE32(const unsigned char* ptr)
 {
-#if HAVE_DECL_LE32TOH == 1
     return le32toh(*((uint32_t*)ptr));
-#elif !defined(WORDS_BIGENDIAN)
-    return *((uint32_t*)ptr);
-#else
-    return ((uint32_t)ptr[3] << 24 | (uint32_t)ptr[2] << 16 | (uint32_t)ptr[1] << 8 | (uint32_t)ptr[0]);
-#endif
 }
 
 uint64_t static inline ReadLE64(const unsigned char* ptr)
 {
-#if HAVE_DECL_LE64TOH == 1
     return le64toh(*((uint64_t*)ptr));
-#elif !defined(WORDS_BIGENDIAN)
-    return *((uint64_t*)ptr);
-#else
-    return ((uint64_t)ptr[7] << 56 | (uint64_t)ptr[6] << 48 | (uint64_t)ptr[5] << 40 | (uint64_t)ptr[4] << 32 |
-            (uint64_t)ptr[3] << 24 | (uint64_t)ptr[2] << 16 | (uint64_t)ptr[1] << 8 | (uint64_t)ptr[0]);
-#endif
+}
+
+void static inline WriteLE16(unsigned char* ptr, uint16_t x)
+{
+    *((uint16_t*)ptr) = htole16(x);
 }
 
 void static inline WriteLE32(unsigned char* ptr, uint32_t x)
 {
-#if HAVE_DECL_HTOLE32 == 1
     *((uint32_t*)ptr) = htole32(x);
-#elif !defined(WORDS_BIGENDIAN)
-    *((uint32_t*)ptr) = x;
-#else
-    ptr[3] = x >> 24;
-    ptr[2] = x >> 16;
-    ptr[1] = x >> 8;
-    ptr[0] = x;
-#endif
 }
 
 void static inline WriteLE64(unsigned char* ptr, uint64_t x)
 {
-#if HAVE_DECL_HTOLE64 == 1
     *((uint64_t*)ptr) = htole64(x);
-#elif !defined(WORDS_BIGENDIAN)
-    *((uint64_t*)ptr) = x;
-#else
-    ptr[7] = x >> 56;
-    ptr[6] = x >> 48;
-    ptr[5] = x >> 40;
-    ptr[4] = x >> 32;
-    ptr[3] = x >> 24;
-    ptr[2] = x >> 16;
-    ptr[1] = x >> 8;
-    ptr[0] = x;
-#endif
 }
 
 uint32_t static inline ReadBE32(const unsigned char* ptr)
 {
-#if HAVE_DECL_BE32TOH == 1
     return be32toh(*((uint32_t*)ptr));
-#else
-    return ((uint32_t)ptr[0] << 24 | (uint32_t)ptr[1] << 16 | (uint32_t)ptr[2] << 8 | (uint32_t)ptr[3]);
-#endif
 }
 
 uint64_t static inline ReadBE64(const unsigned char* ptr)
 {
-#if HAVE_DECL_BE64TOH == 1
     return be64toh(*((uint64_t*)ptr));
-#else
-    return ((uint64_t)ptr[0] << 56 | (uint64_t)ptr[1] << 48 | (uint64_t)ptr[2] << 40 | (uint64_t)ptr[3] << 32 |
-            (uint64_t)ptr[4] << 24 | (uint64_t)ptr[5] << 16 | (uint64_t)ptr[6] << 8 | (uint64_t)ptr[7]);
-#endif
 }
 
 void static inline WriteBE32(unsigned char* ptr, uint32_t x)
 {
-#if HAVE_DECL_HTOBE32 == 1
     *((uint32_t*)ptr) = htobe32(x);
-#else
-    ptr[0] = x >> 24;
-    ptr[1] = x >> 16;
-    ptr[2] = x >> 8;
-    ptr[3] = x;
-#endif
 }
 
 void static inline WriteBE64(unsigned char* ptr, uint64_t x)
 {
-#if HAVE_DECL_HTOBE64 == 1
     *((uint64_t*)ptr) = htobe64(x);
-#else
-    ptr[0] = x >> 56;
-    ptr[1] = x >> 48;
-    ptr[2] = x >> 40;
-    ptr[3] = x >> 32;
-    ptr[4] = x >> 24;
-    ptr[5] = x >> 16;
-    ptr[6] = x >> 8;
-    ptr[7] = x;
-#endif
 }
 
 #endif // BITCOIN_CRYPTO_COMMON_H
diff --git a/src/hash.cpp b/src/hash.cpp
index a7eb5a2a0..20d5d2177 100644
--- a/src/hash.cpp
+++ b/src/hash.cpp
@@ -3,8 +3,10 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include "hash.h"
+#include "crypto/common.h"
 #include "crypto/hmac_sha512.h"
 
+
 inline uint32_t ROTL32(uint32_t x, int8_t r)
 {
     return (x << r) | (x >> (32 - r));
@@ -23,10 +25,10 @@ unsigned int MurmurHash3(unsigned int nHashSeed, const std::vector<unsigned char
 
         //----------
         // body
-        const uint32_t* blocks = (const uint32_t*)(&vDataToHash[0] + nblocks * 4);
+        const uint8_t* blocks = &vDataToHash[0] + nblocks * 4;
 
         for (int i = -nblocks; i; i++) {
-            uint32_t k1 = blocks[i];
+            uint32_t k1 = ReadLE32(blocks + i*4);
 
             k1 *= c1;
             k1 = ROTL32(k1, 15);
diff --git a/src/main.cpp b/src/main.cpp
index b6a61f7da..9927ac759 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -4318,8 +4318,7 @@ bool ProcessMessages(CNode* pfrom)
         // Checksum
         CDataStream& vRecv = msg.vRecv;
         uint256 hash = Hash(vRecv.begin(), vRecv.begin() + nMessageSize);
-        unsigned int nChecksum = 0;
-        memcpy(&nChecksum, &hash, sizeof(nChecksum));
+        unsigned int nChecksum = ReadLE32((unsigned char*)&hash);
         if (nChecksum != hdr.nChecksum)
         {
             LogPrintf("ProcessMessages(%s, %u bytes): CHECKSUM ERROR nChecksum=%08x hdr.nChecksum=%08x\n",
diff --git a/src/net.cpp b/src/net.cpp
index d9f470b9e..08d1d5740 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -14,6 +14,7 @@
 #include "clientversion.h"
 #include "primitives/transaction.h"
 #include "ui_interface.h"
+#include "crypto/common.h"
 
 #ifdef WIN32
 #include <string.h>
@@ -2007,7 +2008,7 @@ void CNode::EndMessage() UNLOCK_FUNCTION(cs_vSend)
 
     // Set the size
     unsigned int nSize = ssSend.size() - CMessageHeader::HEADER_SIZE;
-    memcpy((char*)&ssSend[CMessageHeader::MESSAGE_SIZE_OFFSET], &nSize, sizeof(nSize));
+    WriteLE32((uint8_t*)&ssSend[CMessageHeader::MESSAGE_SIZE_OFFSET], nSize);
 
     // Set the checksum
     uint256 hash = Hash(ssSend.begin() + CMessageHeader::HEADER_SIZE, ssSend.end());
diff --git a/src/netbase.h b/src/netbase.h
index 5bf13a673..b42c2dffa 100644
--- a/src/netbase.h
+++ b/src/netbase.h
@@ -162,7 +162,7 @@ class CService : public CNetAddr
         inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
             READWRITE(FLATDATA(ip));
             unsigned short portN = htons(port);
-            READWRITE(portN);
+            READWRITE(FLATDATA(portN));
             if (ser_action.ForRead())
                  port = ntohs(portN);
         }
diff --git a/src/primitives/block.cpp b/src/primitives/block.cpp
index 3b4a36039..5b9c13d87 100644
--- a/src/primitives/block.cpp
+++ b/src/primitives/block.cpp
@@ -8,10 +8,11 @@
 #include "hash.h"
 #include "tinyformat.h"
 #include "utilstrencodings.h"
+#include "crypto/common.h"
 
 uint256 CBlockHeader::GetHash() const
 {
-    return Hash(BEGIN(nVersion), END(nNonce));
+    return SerializeHash(*this);
 }
 
 uint256 CBlock::BuildMerkleTree(bool* fMutated) const
diff --git a/src/primitives/transaction.h b/src/primitives/transaction.h
index 1b5a47e0d..0ba9affed 100644
--- a/src/primitives/transaction.h
+++ b/src/primitives/transaction.h
@@ -25,7 +25,8 @@ public:
 
     template <typename Stream, typename Operation>
     inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
-        READWRITE(FLATDATA(*this));
+        READWRITE(hash);
+        READWRITE(n);
     }
 
     void SetNull() { hash.SetNull(); n = (uint32_t) -1; }
diff --git a/src/script/script.h b/src/script/script.h
index 8b36aa2f5..ed456f5c5 100644
--- a/src/script/script.h
+++ b/src/script/script.h
@@ -14,6 +14,7 @@
 #include <string.h>
 #include <string>
 #include <vector>
+#include "crypto/common.h"
 
 static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = 520; // bytes
 
@@ -416,14 +417,16 @@ public:
         else if (b.size() <= 0xffff)
         {
             insert(end(), OP_PUSHDATA2);
-            unsigned short nSize = b.size();
-            insert(end(), (unsigned char*)&nSize, (unsigned char*)&nSize + sizeof(nSize));
+            uint8_t data[2];
+            WriteLE16(data, b.size());
+            insert(end(), data, data + sizeof(data));
         }
         else
         {
             insert(end(), OP_PUSHDATA4);
-            unsigned int nSize = b.size();
-            insert(end(), (unsigned char*)&nSize, (unsigned char*)&nSize + sizeof(nSize));
+            uint8_t data[4];
+            WriteLE32(data, b.size());
+            insert(end(), data, data + sizeof(data));
         }
         insert(end(), b.begin(), b.end());
         return *this;
@@ -496,15 +499,14 @@ public:
             {
                 if (end() - pc < 2)
                     return false;
-                nSize = 0;
-                memcpy(&nSize, &pc[0], 2);
+                nSize = ReadLE16(&pc[0]);
                 pc += 2;
             }
             else if (opcode == OP_PUSHDATA4)
             {
                 if (end() - pc < 4)
                     return false;
-                memcpy(&nSize, &pc[0], 4);
+                nSize = ReadLE32(&pc[0]);
                 pc += 4;
             }
             if (end() - pc < 0 || (unsigned int)(end() - pc) < nSize)
diff --git a/src/serialize.h b/src/serialize.h
index a62760a79..741f78f8b 100644
--- a/src/serialize.h
+++ b/src/serialize.h
@@ -18,6 +18,8 @@
 #include <utility>
 #include <vector>
 
+#include "compat/endian.h"
+
 class CScript;
 
 static const unsigned int MAX_SIZE = 0x02000000;
@@ -71,6 +73,79 @@ inline const T* end_ptr(const std::vector<T,TAl>& v)
     return v.empty() ? NULL : (&v[0] + v.size());
 }
 
+/*
+ * Lowest-level serialization and conversion.
+ * @note Sizes of these types are verified in the tests
+ */
+template<typename Stream> inline void ser_writedata8(Stream &s, uint8_t obj)
+{
+    s.write((char*)&obj, 1);
+}
+template<typename Stream> inline void ser_writedata16(Stream &s, uint16_t obj)
+{
+    obj = htole16(obj);
+    s.write((char*)&obj, 2);
+}
+template<typename Stream> inline void ser_writedata32(Stream &s, uint32_t obj)
+{
+    obj = htole32(obj);
+    s.write((char*)&obj, 4);
+}
+template<typename Stream> inline void ser_writedata64(Stream &s, uint64_t obj)
+{
+    obj = htole64(obj);
+    s.write((char*)&obj, 8);
+}
+template<typename Stream> inline uint8_t ser_readdata8(Stream &s)
+{
+    uint8_t obj;
+    s.read((char*)&obj, 1);
+    return obj;
+}
+template<typename Stream> inline uint16_t ser_readdata16(Stream &s)
+{
+    uint16_t obj;
+    s.read((char*)&obj, 2);
+    return le16toh(obj);
+}
+template<typename Stream> inline uint32_t ser_readdata32(Stream &s)
+{
+    uint32_t obj;
+    s.read((char*)&obj, 4);
+    return le32toh(obj);
+}
+template<typename Stream> inline uint64_t ser_readdata64(Stream &s)
+{
+    uint64_t obj;
+    s.read((char*)&obj, 8);
+    return le64toh(obj);
+}
+inline uint64_t ser_double_to_uint64(double x)
+{
+    union { double x; uint64_t y; } tmp;
+    tmp.x = x;
+    return tmp.y;
+}
+inline uint32_t ser_float_to_uint32(float x)
+{
+    union { float x; uint32_t y; } tmp;
+    tmp.x = x;
+    return tmp.y;
+}
+inline double ser_uint64_to_double(uint64_t y)
+{
+    union { double x; uint64_t y; } tmp;
+    tmp.y = y;
+    return tmp.x;
+}
+inline float ser_uint32_to_float(uint32_t y)
+{
+    union { float x; uint32_t y; } tmp;
+    tmp.y = y;
+    return tmp.x;
+}
+
+
 /////////////////////////////////////////////////////////////////
 //
 // Templates for serializing to anything that looks like a stream,
@@ -108,59 +183,48 @@ enum
         SerializationOp(s, CSerActionUnserialize(), nType, nVersion);                \
     }
 
-
-
 /*
  * Basic Types
  */
-#define WRITEDATA(s, obj)   s.write((char*)&(obj), sizeof(obj))
-#define READDATA(s, obj)    s.read((char*)&(obj), sizeof(obj))
-
-inline unsigned int GetSerializeSize(char a,               int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(signed char a,        int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(unsigned char a,      int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(signed short a,       int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(unsigned short a,     int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(signed int a,         int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(unsigned int a,       int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(signed long a,        int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(unsigned long a,      int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(signed long long a,   int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(unsigned long long a, int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(float a,              int, int=0) { return sizeof(a); }
-inline unsigned int GetSerializeSize(double a,             int, int=0) { return sizeof(a); }
-
-template<typename Stream> inline void Serialize(Stream& s, char a,               int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, signed char a,        int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, unsigned char a,      int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, signed short a,       int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, unsigned short a,     int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, signed int a,         int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, unsigned int a,       int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, signed long a,        int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, unsigned long a,      int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, signed long long a,   int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, unsigned long long a, int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, float a,              int, int=0) { WRITEDATA(s, a); }
-template<typename Stream> inline void Serialize(Stream& s, double a,             int, int=0) { WRITEDATA(s, a); }
-
-template<typename Stream> inline void Unserialize(Stream& s, char& a,               int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, signed char& a,        int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, unsigned char& a,      int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, signed short& a,       int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, unsigned short& a,     int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, signed int& a,         int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, unsigned int& a,       int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, signed long& a,        int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, unsigned long& a,      int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, signed long long& a,   int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, unsigned long long& a, int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, float& a,              int, int=0) { READDATA(s, a); }
-template<typename Stream> inline void Unserialize(Stream& s, double& a,             int, int=0) { READDATA(s, a); }
+inline unsigned int GetSerializeSize(char a,      int, int=0) { return 1; }
+inline unsigned int GetSerializeSize(int8_t a,    int, int=0) { return 1; }
+inline unsigned int GetSerializeSize(uint8_t a,   int, int=0) { return 1; }
+inline unsigned int GetSerializeSize(int16_t a,   int, int=0) { return 2; }
+inline unsigned int GetSerializeSize(uint16_t a,  int, int=0) { return 2; }
+inline unsigned int GetSerializeSize(int32_t a,   int, int=0) { return 4; }
+inline unsigned int GetSerializeSize(uint32_t a,  int, int=0) { return 4; }
+inline unsigned int GetSerializeSize(int64_t a,   int, int=0) { return 8; }
+inline unsigned int GetSerializeSize(uint64_t a,  int, int=0) { return 8; }
+inline unsigned int GetSerializeSize(float a,     int, int=0) { return 4; }
+inline unsigned int GetSerializeSize(double a,    int, int=0) { return 8; }
+
+template<typename Stream> inline void Serialize(Stream& s, char a,         int, int=0) { ser_writedata8(s, a); } // TODO Get rid of bare char
+template<typename Stream> inline void Serialize(Stream& s, int8_t a,       int, int=0) { ser_writedata8(s, a); }
+template<typename Stream> inline void Serialize(Stream& s, uint8_t a,      int, int=0) { ser_writedata8(s, a); }
+template<typename Stream> inline void Serialize(Stream& s, int16_t a,      int, int=0) { ser_writedata16(s, a); }
+template<typename Stream> inline void Serialize(Stream& s, uint16_t a,     int, int=0) { ser_writedata16(s, a); }
+template<typename Stream> inline void Serialize(Stream& s, int32_t a,      int, int=0) { ser_writedata32(s, a); }
+template<typename Stream> inline void Serialize(Stream& s, uint32_t a,     int, int=0) { ser_writedata32(s, a); }
+template<typename Stream> inline void Serialize(Stream& s, int64_t a,      int, int=0) { ser_writedata64(s, a); }
+template<typename Stream> inline void Serialize(Stream& s, uint64_t a,     int, int=0) { ser_writedata64(s, a); }
+template<typename Stream> inline void Serialize(Stream& s, float a,        int, int=0) { ser_writedata32(s, ser_float_to_uint32(a)); }
+template<typename Stream> inline void Serialize(Stream& s, double a,       int, int=0) { ser_writedata64(s, ser_double_to_uint64(a)); }
+
+template<typename Stream> inline void Unserialize(Stream& s, char& a,      int, int=0) { a = ser_readdata8(s); } // TODO Get rid of bare char
+template<typename Stream> inline void Unserialize(Stream& s, int8_t& a,    int, int=0) { a = ser_readdata8(s); }
+template<typename Stream> inline void Unserialize(Stream& s, uint8_t& a,   int, int=0) { a = ser_readdata8(s); }
+template<typename Stream> inline void Unserialize(Stream& s, int16_t& a,   int, int=0) { a = ser_readdata16(s); }
+template<typename Stream> inline void Unserialize(Stream& s, uint16_t& a,  int, int=0) { a = ser_readdata16(s); }
+template<typename Stream> inline void Unserialize(Stream& s, int32_t& a,   int, int=0) { a = ser_readdata32(s); }
+template<typename Stream> inline void Unserialize(Stream& s, uint32_t& a,  int, int=0) { a = ser_readdata32(s); }
+template<typename Stream> inline void Unserialize(Stream& s, int64_t& a,   int, int=0) { a = ser_readdata64(s); }
+template<typename Stream> inline void Unserialize(Stream& s, uint64_t& a,  int, int=0) { a = ser_readdata64(s); }
+template<typename Stream> inline void Unserialize(Stream& s, float& a,     int, int=0) { a = ser_uint32_to_float(ser_readdata32(s)); }
+template<typename Stream> inline void Unserialize(Stream& s, double& a,    int, int=0) { a = ser_uint64_to_double(ser_readdata64(s)); }
 
 inline unsigned int GetSerializeSize(bool a, int, int=0)                          { return sizeof(char); }
-template<typename Stream> inline void Serialize(Stream& s, bool a, int, int=0)    { char f=a; WRITEDATA(s, f); }
-template<typename Stream> inline void Unserialize(Stream& s, bool& a, int, int=0) { char f; READDATA(s, f); a=f; }
+template<typename Stream> inline void Serialize(Stream& s, bool a, int, int=0)    { char f=a; ser_writedata8(s, f); }
+template<typename Stream> inline void Unserialize(Stream& s, bool& a, int, int=0) { char f=ser_readdata8(s); a=f; }
 
 
 
@@ -187,29 +251,22 @@ void WriteCompactSize(Stream& os, uint64_t nSize)
 {
     if (nSize < 253)
     {
-        unsigned char chSize = nSize;
-        WRITEDATA(os, chSize);
+        ser_writedata8(os, nSize);
     }
     else if (nSize <= std::numeric_limits<unsigned short>::max())
     {
-        unsigned char chSize = 253;
-        unsigned short xSize = nSize;
-        WRITEDATA(os, chSize);
-        WRITEDATA(os, xSize);
+        ser_writedata8(os, 253);
+        ser_writedata16(os, nSize);
     }
     else if (nSize <= std::numeric_limits<unsigned int>::max())
     {
-        unsigned char chSize = 254;
-        unsigned int xSize = nSize;
-        WRITEDATA(os, chSize);
-        WRITEDATA(os, xSize);
+        ser_writedata8(os, 254);
+        ser_writedata32(os, nSize);
     }
     else
     {
-        unsigned char chSize = 255;
-        uint64_t xSize = nSize;
-        WRITEDATA(os, chSize);
-        WRITEDATA(os, xSize);
+        ser_writedata8(os, 255);
+        ser_writedata64(os, nSize);
     }
     return;
 }
@@ -217,8 +274,7 @@ void WriteCompactSize(Stream& os, uint64_t nSize)
 template<typename Stream>
 uint64_t ReadCompactSize(Stream& is)
 {
-    unsigned char chSize;
-    READDATA(is, chSize);
+    uint8_t chSize = ser_readdata8(is);
     uint64_t nSizeRet = 0;
     if (chSize < 253)
     {
@@ -226,25 +282,19 @@ uint64_t ReadCompactSize(Stream& is)
     }
     else if (chSize == 253)
     {
-        unsigned short xSize;
-        READDATA(is, xSize);
-        nSizeRet = xSize;
+        nSizeRet = ser_readdata16(is);
         if (nSizeRet < 253)
             throw std::ios_base::failure("non-canonical ReadCompactSize()");
     }
     else if (chSize == 254)
     {
-        unsigned int xSize;
-        READDATA(is, xSize);
-        nSizeRet = xSize;
+        nSizeRet = ser_readdata32(is);
         if (nSizeRet < 0x10000u)
             throw std::ios_base::failure("non-canonical ReadCompactSize()");
     }
     else
     {
-        uint64_t xSize;
-        READDATA(is, xSize);
-        nSizeRet = xSize;
+        nSizeRet = ser_readdata64(is);
         if (nSizeRet < 0x100000000ULL)
             throw std::ios_base::failure("non-canonical ReadCompactSize()");
     }
@@ -303,7 +353,7 @@ void WriteVarInt(Stream& os, I n)
         len++;
     }
     do {
-        WRITEDATA(os, tmp[len]);
+        ser_writedata8(os, tmp[len]);
     } while(len--);
 }
 
@@ -312,8 +362,7 @@ I ReadVarInt(Stream& is)
 {
     I n = 0;
     while(true) {
-        unsigned char chData;
-        READDATA(is, chData);
+        unsigned char chData = ser_readdata8(is);
         n = (n << 7) | (chData & 0x7F);
         if (chData & 0x80)
             n++;
diff --git a/src/test/serialize_tests.cpp b/src/test/serialize_tests.cpp
index fe49af711..de9510d54 100644
--- a/src/test/serialize_tests.cpp
+++ b/src/test/serialize_tests.cpp
@@ -4,6 +4,7 @@
 
 #include "serialize.h"
 #include "streams.h"
+#include "hash.h"
 
 #include <stdint.h>
 
@@ -13,6 +14,119 @@ using namespace std;
 
 BOOST_AUTO_TEST_SUITE(serialize_tests)
 
+BOOST_AUTO_TEST_CASE(sizes)
+{
+    BOOST_CHECK_EQUAL(sizeof(char), GetSerializeSize(char(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(int8_t), GetSerializeSize(int8_t(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(uint8_t), GetSerializeSize(uint8_t(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(int16_t), GetSerializeSize(int16_t(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(uint16_t), GetSerializeSize(uint16_t(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(int32_t), GetSerializeSize(int32_t(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(uint32_t), GetSerializeSize(uint32_t(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(int64_t), GetSerializeSize(int64_t(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(uint64_t), GetSerializeSize(uint64_t(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(float), GetSerializeSize(float(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(double), GetSerializeSize(double(0), 0));
+    // Bool is serialized as char
+    BOOST_CHECK_EQUAL(sizeof(char), GetSerializeSize(bool(0), 0));
+
+    // Sanity-check GetSerializeSize and c++ type matching
+    BOOST_CHECK_EQUAL(GetSerializeSize(char(0), 0), 1);
+    BOOST_CHECK_EQUAL(GetSerializeSize(int8_t(0), 0), 1);
+    BOOST_CHECK_EQUAL(GetSerializeSize(uint8_t(0), 0), 1);
+    BOOST_CHECK_EQUAL(GetSerializeSize(int16_t(0), 0), 2);
+    BOOST_CHECK_EQUAL(GetSerializeSize(uint16_t(0), 0), 2);
+    BOOST_CHECK_EQUAL(GetSerializeSize(int32_t(0), 0), 4);
+    BOOST_CHECK_EQUAL(GetSerializeSize(uint32_t(0), 0), 4);
+    BOOST_CHECK_EQUAL(GetSerializeSize(int64_t(0), 0), 8);
+    BOOST_CHECK_EQUAL(GetSerializeSize(uint64_t(0), 0), 8);
+    BOOST_CHECK_EQUAL(GetSerializeSize(float(0), 0), 4);
+    BOOST_CHECK_EQUAL(GetSerializeSize(double(0), 0), 8);
+    BOOST_CHECK_EQUAL(GetSerializeSize(bool(0), 0), 1);
+}
+
+BOOST_AUTO_TEST_CASE(floats_conversion)
+{
+    // Choose values that map unambigiously to binary floating point to avoid
+    // rounding issues at the compiler side.
+    BOOST_CHECK_EQUAL(ser_uint32_to_float(0x00000000), 0.0F);
+    BOOST_CHECK_EQUAL(ser_uint32_to_float(0x3f000000), 0.5F);
+    BOOST_CHECK_EQUAL(ser_uint32_to_float(0x3f800000), 1.0F);
+    BOOST_CHECK_EQUAL(ser_uint32_to_float(0x40000000), 2.0F);
+    BOOST_CHECK_EQUAL(ser_uint32_to_float(0x40800000), 4.0F);
+    BOOST_CHECK_EQUAL(ser_uint32_to_float(0x44444444), 785.066650390625F);
+
+    BOOST_CHECK_EQUAL(ser_float_to_uint32(0.0F), 0x00000000);
+    BOOST_CHECK_EQUAL(ser_float_to_uint32(0.5F), 0x3f000000);
+    BOOST_CHECK_EQUAL(ser_float_to_uint32(1.0F), 0x3f800000);
+    BOOST_CHECK_EQUAL(ser_float_to_uint32(2.0F), 0x40000000);
+    BOOST_CHECK_EQUAL(ser_float_to_uint32(4.0F), 0x40800000);
+    BOOST_CHECK_EQUAL(ser_float_to_uint32(785.066650390625F), 0x44444444);
+}
+
+BOOST_AUTO_TEST_CASE(doubles_conversion)
+{
+    // Choose values that map unambigiously to binary floating point to avoid
+    // rounding issues at the compiler side.
+    BOOST_CHECK_EQUAL(ser_uint64_to_double(0x0000000000000000ULL), 0.0);
+    BOOST_CHECK_EQUAL(ser_uint64_to_double(0x3fe0000000000000ULL), 0.5);
+    BOOST_CHECK_EQUAL(ser_uint64_to_double(0x3ff0000000000000ULL), 1.0);
+    BOOST_CHECK_EQUAL(ser_uint64_to_double(0x4000000000000000ULL), 2.0);
+    BOOST_CHECK_EQUAL(ser_uint64_to_double(0x4010000000000000ULL), 4.0);
+    BOOST_CHECK_EQUAL(ser_uint64_to_double(0x4088888880000000ULL), 785.066650390625);
+
+    BOOST_CHECK_EQUAL(ser_double_to_uint64(0.0), 0x0000000000000000ULL);
+    BOOST_CHECK_EQUAL(ser_double_to_uint64(0.5), 0x3fe0000000000000ULL);
+    BOOST_CHECK_EQUAL(ser_double_to_uint64(1.0), 0x3ff0000000000000ULL);
+    BOOST_CHECK_EQUAL(ser_double_to_uint64(2.0), 0x4000000000000000ULL);
+    BOOST_CHECK_EQUAL(ser_double_to_uint64(4.0), 0x4010000000000000ULL);
+    BOOST_CHECK_EQUAL(ser_double_to_uint64(785.066650390625), 0x4088888880000000ULL);
+}
+/*
+Python code to generate the below hashes:
+
+    def reversed_hex(x):
+        return binascii.hexlify(''.join(reversed(x)))
+    def dsha256(x):
+        return hashlib.sha256(hashlib.sha256(x).digest()).digest()
+
+    reversed_hex(dsha256(''.join(struct.pack('<f', x) for x in range(0,1000)))) == '8e8b4cf3e4df8b332057e3e23af42ebc663b61e0495d5e7e32d85099d7f3fe0c'
+    reversed_hex(dsha256(''.join(struct.pack('<d', x) for x in range(0,1000)))) == '43d0c82591953c4eafe114590d392676a01585d25b25d433557f0d7878b23f96'
+*/
+BOOST_AUTO_TEST_CASE(floats)
+{
+    CDataStream ss(SER_DISK, 0);
+    // encode
+    for (int i = 0; i < 1000; i++) {
+        ss << float(i);
+    }
+    BOOST_CHECK(Hash(ss.begin(), ss.end()) == uint256S("8e8b4cf3e4df8b332057e3e23af42ebc663b61e0495d5e7e32d85099d7f3fe0c"));
+
+    // decode
+    for (int i = 0; i < 1000; i++) {
+        float j;
+        ss >> j;
+        BOOST_CHECK_MESSAGE(i == j, "decoded:" << j << " expected:" << i);
+    }
+}
+
+BOOST_AUTO_TEST_CASE(doubles)
+{
+    CDataStream ss(SER_DISK, 0);
+    // encode
+    for (int i = 0; i < 1000; i++) {
+        ss << double(i);
+    }
+    BOOST_CHECK(Hash(ss.begin(), ss.end()) == uint256S("43d0c82591953c4eafe114590d392676a01585d25b25d433557f0d7878b23f96"));
+
+    // decode
+    for (int i = 0; i < 1000; i++) {
+        double j;
+        ss >> j;
+        BOOST_CHECK_MESSAGE(i == j, "decoded:" << j << " expected:" << i);
+    }
+}
+
 BOOST_AUTO_TEST_CASE(varints)
 {
     // encode
diff --git a/src/txmempool.cpp b/src/txmempool.cpp
index 6e0f7e9c5..0d5066032 100644
--- a/src/txmempool.cpp
+++ b/src/txmempool.cpp
@@ -337,7 +337,7 @@ public:
     void Write(CAutoFile& fileout) const
     {
         fileout << nBestSeenHeight;
-        fileout << history.size();
+        fileout << (uint32_t)history.size();
         BOOST_FOREACH(const CBlockAverage& entry, history)
         {
             entry.Write(fileout);
@@ -348,7 +348,7 @@ public:
     {
         int nFileBestSeenHeight;
         filein >> nFileBestSeenHeight;
-        size_t numEntries;
+        uint32_t numEntries;
         filein >> numEntries;
         if (numEntries <= 0 || numEntries > 10000)
             throw runtime_error("Corrupt estimates file. Must have between 1 and 10k entries.");