diff --git a/.gitmodules b/.gitmodules
index 8cc85d0e..c155a04c 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -193,3 +193,9 @@
 [submodule "vendor/npeg"]
 	path = vendor/npeg
 	url = https://github.com/zevv/npeg
+[submodule "vendor/nim-poseidon2"]
+	path = vendor/nim-poseidon2
+	url = https://github.com/codex-storage/nim-poseidon2.git
+[submodule "vendor/constantine"]
+	path = vendor/constantine
+	url = https://github.com/mratsim/constantine.git
diff --git a/codex.nimble b/codex.nimble
index e1200d71..df89e043 100644
--- a/codex.nimble
+++ b/codex.nimble
@@ -30,5 +30,6 @@ requires "leopard >= 0.1.0 & < 0.2.0"
 requires "blscurve"
 requires "libp2pdht"
 requires "eth"
+requires "https://github.com/codex-storage/nim-poseidon2.git >= 0.1.0 & < 0.2.0"
 
 include "build.nims"
diff --git a/config.nims b/config.nims
index 3c02c598..031cdaa7 100644
--- a/config.nims
+++ b/config.nims
@@ -113,6 +113,9 @@ switch("define", "libp2p_pki_schemes=secp256k1")
 # we can't use it. And codex.cfg doesn't work
 switch("define", "chronicles_sinks=textlines[dynamic],json[dynamic],textlines[dynamic]")
 
+# Workaround for assembler incompatibility between constantine and secp256k1
+switch("define", "use_asm_syntax_intel=false")
+
 # begin Nimble config (version 1)
 when system.fileExists("nimble.paths"):
   include "nimble.paths"
diff --git a/vendor/constantine b/vendor/constantine
new file mode 160000
index 00000000..5f7ba18f
--- /dev/null
+++ b/vendor/constantine
@@ -0,0 +1 @@
+Subproject commit 5f7ba18f2ed351260015397c9eae079a6decaee1
diff --git a/vendor/nim-poseidon2 b/vendor/nim-poseidon2
new file mode 160000
index 00000000..af673749
--- /dev/null
+++ b/vendor/nim-poseidon2
@@ -0,0 +1 @@
+Subproject commit af6737492971dd05b2a6b03404e490f865266f15