diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index e54f3e0e1..fa324dd11 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -109,3 +109,14 @@ cmake-test:
       coverage_report:
         coverage_format: cobertura
         path: coverage.xml
+
+amalgamation-test:
+  image: greenaddress/wallycore@sha256:956b107d688f549c6e3884424991b7d3d34d84173990d43046fd760d7918db7c
+  tags:
+    - ga
+  script:
+    - touch config.h
+    - gcc -Wall -W -Wextra -Werror -I. -I./src -I./src/ccan -I./src/secp256k1/include src/ctest/amalgamation_compile_test.c
+    - gcc -DBUILD_ELEMENTS -Wall -W -Wextra -Werror -I. -I./src -I./src/ccan -I./src/secp256k1/include src/ctest/amalgamation_compile_test.c
+    - clang -Wall -W -Wextra -Werror -I. -I./src -I./src/ccan -I./src/secp256k1/include src/ctest/amalgamation_compile_test.c
+    - clang -DBUILD_ELEMENTS -Wall -W -Wextra -Werror -I. -I./src -I./src/ccan -I./src/secp256k1/include src/ctest/amalgamation_compile_test.c
diff --git a/setup.py b/setup.py
index 4e4c47417..ab1a0e9e1 100644
--- a/setup.py
+++ b/setup.py
@@ -128,9 +128,7 @@ def _call(args, cwd=ABS_PATH):
         './src/secp256k1/include',
     ]
     sources += [
-        'src/amalgamation/combined.c',
-        'src/amalgamation/combined_ccan.c',
-        'src/amalgamation/combined_ccan2.c',
+        'src/amalgamation/combined.c'
     ]
 else:
     # Compile the swig python wrapper file and link it with wally/secp
diff --git a/src/amalgamation/combined.c b/src/amalgamation/combined.c
index c60d4dcca..206544232 100644
--- a/src/amalgamation/combined.c
+++ b/src/amalgamation/combined.c
@@ -6,9 +6,9 @@
 #define ENABLE_MODULE_SCHNORRSIG 1
 #define ENABLE_MODULE_GENERATOR 1
 #define ENABLE_MODULE_ECDSA_S2C 1
+#define ENABLE_MODULE_RECOVERY 1
 #ifdef BUILD_ELEMENTS
 #define ENABLE_MODULE_RANGEPROOF 1
-#define ENABLE_MODULE_RECOVERY 1
 #define ENABLE_MODULE_SURJECTIONPROOF 1
 #define ENABLE_MODULE_WHITELIST 1
 #endif
@@ -33,38 +33,85 @@
 #include "src/secp256k1/src/secp256k1.c"
 #include "src/secp256k1/src/precomputed_ecmult_gen.c"
 #include "src/secp256k1/src/precomputed_ecmult.c"
-#include "ccan/ccan/crypto/sha256/sha256.c"
 
-#include "internal.c"
-#include "address.c"
-#include "aes.c"
-#include "anti_exfil.c"
-#include "base_58.c"
-#include "base_64.c"
-#include "bech32.c"
-#include "blech32.c"
-#include "bip32.c"
-#include "bip38.c"
-#include "bip39.c"
-#include "bip85.c"
-#include "coins.c"
-#include "descriptor.c"
-#include "ecdh.c"
-#include "elements.c"
-#include "hex_.c"
-#include "hmac.c"
-#include "map.c"
-#include "mnemonic.c"
-#include "pbkdf2.c"
-#include "pullpush.c"
-#include "psbt.c"
-#include "script.c"
-#include "scrypt.c"
-#include "sign.c"
-#include "symmetric.c"
-#include "transaction.c"
-#include "wif.c"
-#include "wordlist.c"
+/* Force the inclusion of our internal header first, so that
+ * config.h (which must be provided by the amalgamation user)
+ * is included.
+ */
+#include "src/internal.h"
+
+/* The amalgamation user can provide their own defines and skip
+ * providing a ccan_config.h if they define _WALLY_CCAN_CONFIG_H_.
+ */
+#ifndef _WALLY_CCAN_CONFIG_H_
+#include "src/ccan_config.h"
+#endif
+
+#include "src/internal.c"
+#include "src/address.c"
+#include "src/aes.c"
+#include "src/anti_exfil.c"
+#include "src/base_58.c"
+#include "src/base_64.c"
+#include "src/bech32.c"
+#include "src/blech32.c"
+#include "src/bip32.c"
+#include "src/bip38.c"
+#include "src/bip39.c"
+#include "src/bip85.c"
+#include "src/coins.c"
+#include "src/descriptor.c"
+#include "src/ecdh.c"
+#include "src/elements.c"
+#include "src/hex_.c"
+#include "src/hmac.c"
+#include "src/map.c"
+#include "src/mnemonic.c"
+#include "src/pbkdf2.c"
+#include "src/pullpush.c"
+#include "src/psbt.c"
+#include "src/script.c"
+#include "src/scrypt.c"
+#include "src/sign.c"
+#include "src/symmetric.c"
+#include "src/transaction.c"
+#include "src/wif.c"
+#include "src/wordlist.c"
+
+/* ccan sources */
+#include "src/ccan/ccan/crypto/sha256/sha256.c"
+
+/* Redefine internal names so sha-512 can be included without conflicts */
+#define Round Round_512
+#define Transform Transform_512
+#define Maj Maj_512
+#define Sigma0 Sigma0_512
+#define sigma0 sigma0_512
+#define Sigma1 Sigma1_512
+#define sigma1 sigma1_512
+#define add add_512
+#define Ch Ch_512
+#include "src/ccan/ccan/crypto/sha512/sha512.c"
+#undef Round
+#undef Transform
+#undef Sigma0
+#undef sigma0
+#undef sigma1
+#undef Sigma1
+#undef add
+#undef Maj
+#undef Ch
+#include "src/ccan/ccan/str/hex/hex.c"
+
+/* Redefine internal names so ripemd-160 can be included without conflicts */
+#define Transform Transform_ripemd160
+#define add add_ripemd160
+#define Round Round_ripemd160
+#include "src/ccan/ccan/crypto/ripemd160/ripemd160.c"
+#undef Transform
+#undef add
+#undef Round
+#include "src/ccan/ccan/base64/base64.c"
 
 void wally_silence_unused_warnings(void)
 {
diff --git a/src/amalgamation/combined_ccan.c b/src/amalgamation/combined_ccan.c
deleted file mode 100644
index aad03f92a..000000000
--- a/src/amalgamation/combined_ccan.c
+++ /dev/null
@@ -1,4 +0,0 @@
-#include "internal.h"
-#include "ccan/ccan/crypto/sha512/sha512.c"
-#include "ccan/ccan/str/hex/hex.c"
-
diff --git a/src/amalgamation/combined_ccan2.c b/src/amalgamation/combined_ccan2.c
deleted file mode 100644
index e74d46429..000000000
--- a/src/amalgamation/combined_ccan2.c
+++ /dev/null
@@ -1,3 +0,0 @@
-#include "internal.h"
-#include "ccan/ccan/crypto/ripemd160/ripemd160.c"
-#include "src/ccan/ccan/base64/base64.c"
diff --git a/src/bip38.c b/src/bip38.c
index 043ff2382..aec52d4ad 100644
--- a/src/bip38.c
+++ b/src/bip38.c
@@ -123,14 +123,14 @@ static int address_from_private_key(const unsigned char *bytes,
     return ret;
 }
 
-static void aes_enc_impl(const unsigned char *src, const unsigned char *xor,
+static void aes_enc_impl(const unsigned char *src, const unsigned char *xor_bytes,
                          const unsigned char *key, unsigned char *bytes_out)
 {
     unsigned char plaintext[AES_BLOCK_LEN];
     size_t i;
 
     for (i = 0; i < sizeof(plaintext); ++i)
-        plaintext[i] = src[i] ^ xor[i];
+        plaintext[i] = src[i] ^ xor_bytes[i];
 
     wally_aes(key, AES_KEY_LEN_256, plaintext, AES_BLOCK_LEN,
               AES_FLAG_ENCRYPT, bytes_out, AES_BLOCK_LEN);
@@ -219,7 +219,7 @@ int bip38_from_private_key(const unsigned char *bytes, size_t bytes_len,
 }
 
 
-static void aes_dec_impl(const unsigned char *cyphertext, const unsigned char *xor,
+static void aes_dec_impl(const unsigned char *cyphertext, const unsigned char *xor_bytes,
                          const unsigned char *key, unsigned char *bytes_out)
 {
     size_t i;
@@ -230,7 +230,7 @@ static void aes_dec_impl(const unsigned char *cyphertext, const unsigned char *x
               bytes_out, AES_BLOCK_LEN);
 
     for (i = 0; i < AES_BLOCK_LEN; ++i)
-        bytes_out[i] ^= xor[i];
+        bytes_out[i] ^= xor_bytes[i];
 }
 
 static int to_private_key(const char *bip38,
diff --git a/src/ccan_config.h b/src/ccan_config.h
index 3556db6b0..87ea13607 100644
--- a/src/ccan_config.h
+++ b/src/ccan_config.h
@@ -1,4 +1,8 @@
+#ifndef _WALLY_CCAN_CONFIG_H_
+#define _WALLY_CCAN_CONFIG_H_ 1
+
 /* Config directives for ccan */
+
 #include <stddef.h>
 
 #ifdef WORDS_BIGENDIAN
@@ -55,3 +59,5 @@
 void wally_clear(void *p, size_t len);
 
 #define CCAN_CLEAR_MEMORY(p, len) wally_clear(p, len)
+
+#endif /*_WALLY_CCAN_CONFIG_H_ */
diff --git a/src/ctest/amalgamation_compile_test.c b/src/ctest/amalgamation_compile_test.c
new file mode 100644
index 000000000..7b0e331c6
--- /dev/null
+++ b/src/ctest/amalgamation_compile_test.c
@@ -0,0 +1,11 @@
+/* Tests that including the entire library as a single source file works */
+#include "../amalgamation/combined.c"
+
+int main(int argc, char *argv[])
+{
+    (void) argc;
+    (void) argv;
+
+    wally_init(0);
+    return wally_cleanup(0);
+}
diff --git a/src/transaction.c b/src/transaction.c
index d132f0cd0..aa84279cb 100644
--- a/src/transaction.c
+++ b/src/transaction.c
@@ -1969,7 +1969,9 @@ int wally_tx_get_vsize(const struct wally_tx *tx, size_t *written)
 int wally_tx_get_elements_weight_discount(const struct wally_tx *tx,
                                           uint32_t flags, size_t *written)
 {
+#ifdef BUILD_ELEMENTS
     size_t i, n = 0, is_elements = 0;
+#endif /* BUILD_ELEMENTS */
 
     if (written)
         *written = 0;
@@ -2004,7 +2006,7 @@ int wally_tx_get_elements_weight_discount(const struct wally_tx *tx,
         }
     }
     *written = n;
-#endif
+#endif /* BUILD_ELEMENTS */
     return WALLY_OK;
 }
 #endif /* WALLY_ABI_NO_ELEMENTS */
diff --git a/tools/msvc/build.bat b/tools/msvc/build.bat
index b074e616b..5a9e753de 100644
--- a/tools/msvc/build.bat
+++ b/tools/msvc/build.bat
@@ -7,4 +7,4 @@ if "%ELEMENTS_BUILD%" == "elements" (
 )
 
 REM Compile everything (wally, ccan, libsecp256k) in one lump.
-cl /utf-8 /DWALLY_CORE_BUILD %OPTS% /I%LIBWALLY_DIR% /I%LIBWALLY_DIR%\src /I%LIBWALLY_DIR%\include /I%LIBWALLY_DIR%\src\ccan /I%LIBWALLY_DIR%\src\ccan\base64 /I%LIBWALLY_DIR%\src\secp256k1 /Zi /LD src/amalgamation/combined.c src/amalgamation/combined_ccan.c src/amalgamation/combined_ccan2.c /Fewally.dll
+cl /utf-8 /DWALLY_CORE_BUILD %OPTS% /I%LIBWALLY_DIR% /I%LIBWALLY_DIR%\src /I%LIBWALLY_DIR%\include /I%LIBWALLY_DIR%\src\ccan /I%LIBWALLY_DIR%\src\ccan\base64 /I%LIBWALLY_DIR%\src\secp256k1 /Zi /LD src/amalgamation/combined.c /Fewally.dll