diff --git a/.gitmodules b/.gitmodules
index 762351f..e298690 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -10,3 +10,6 @@
 [submodule "hash/cpu/src/Blake3"]
 	path = hash/cpu/src/Blake3
 	url = https://github.com/BLAKE3-team/BLAKE3
+[submodule "hash/snark/src/hash-circuits"]
+	path = hash/snark/external/hash-circuits
+	url = https://github.com/faulhornlabs/hash-circuits
diff --git a/ceremony/.gitignore b/ceremony/.gitignore
new file mode 100644
index 0000000..e7fbb28
--- /dev/null
+++ b/ceremony/.gitignore
@@ -0,0 +1 @@
+*.ptau
diff --git a/ceremony/README.md b/ceremony/README.md
new file mode 100644
index 0000000..dc273fe
--- /dev/null
+++ b/ceremony/README.md
@@ -0,0 +1,8 @@
+
+Location for the trusted setup ceremony file
+--------------------------------------------
+
+Copy or symlink the ceremony file here with the name `ceremony.ptau`.
+
+You can find links to the Hermez ceremony files (up to size `2^28`)
+[in the `snarkjs` readme](https://github.com/iden3/snarkjs).
diff --git a/ceremony/setup.sh b/ceremony/setup.sh
new file mode 100755
index 0000000..d78905f
--- /dev/null
+++ b/ceremony/setup.sh
@@ -0,0 +1,14 @@
+#!/bin/bash
+
+if [ -z ${ZKBENCH_CEREMONY_SIZE} ]; then
+ZKBENCH_CEREMONY_SIZE=16
+fi
+
+echo "ceremony size = ${ZKBENCH_CEREMONY_SIZE}"
+
+snarkjs powersoftau new bn128 ${ZKBENCH_CEREMONY_SIZE} pot_0000.ptau
+echo foobar | snarkjs powersoftau contribute pot_0000.ptau pot_0001.ptau --name="First contribution" 
+snarkjs powersoftau prepare phase2 pot_0001.ptau ceremony.ptau
+
+rm pot20_0000.ptau
+mv pot20_0001.ptau ceremony.ptau
diff --git a/hash/cpu/README.md b/hash/cpu/README.md
new file mode 100644
index 0000000..c4ad07a
--- /dev/null
+++ b/hash/cpu/README.md
@@ -0,0 +1,7 @@
+
+Hash functions CPU benchmarks
+-----------------------------
+
+- `bench` contains the benchmarking scripts
+- `src` contains the 3rd party dependencies as git submodules
+
diff --git a/hash/snark/README.md b/hash/snark/README.md
new file mode 100644
index 0000000..841dc2d
--- /dev/null
+++ b/hash/snark/README.md
@@ -0,0 +1,7 @@
+
+Hash functions SNARK benchmarks
+--------------------------------
+
+- `bench` contains the benchmarking scripts
+- `external` contains the 3rd party dependencies as git submodules
+
diff --git a/hash/snark/bench/Poseidon2/.gitignore b/hash/snark/bench/Poseidon2/.gitignore
new file mode 100644
index 0000000..c795b05
--- /dev/null
+++ b/hash/snark/bench/Poseidon2/.gitignore
@@ -0,0 +1 @@
+build
\ No newline at end of file
diff --git a/hash/snark/bench/Poseidon2/build.sh b/hash/snark/bench/Poseidon2/build.sh
new file mode 100755
index 0000000..60147eb
--- /dev/null
+++ b/hash/snark/bench/Poseidon2/build.sh
@@ -0,0 +1,15 @@
+#!/bin/bash
+
+ORIG=`pwd`
+
+mkdir -p build 
+
+gcc -O3 generate_input.c -o build/generate_input || { echo "gcc failed"; exit 101; }
+
+sed "s/ZKBENCH_INPUT_SIZE/${ZKBENCH_INPUT_SIZE}/g" hash_sponge.circom.template >build/hash_sponge.circom
+
+cd build
+
+circom hash_sponge.circom --r1cs --wasm || { echo "circom failed"; exit 102; }
+ 
+cd $ORIG
\ No newline at end of file
diff --git a/hash/snark/bench/Poseidon2/generate_input.c b/hash/snark/bench/Poseidon2/generate_input.c
new file mode 100644
index 0000000..430abb2
--- /dev/null
+++ b/hash/snark/bench/Poseidon2/generate_input.c
@@ -0,0 +1,36 @@
+
+#include <stdio.h>
+#include <stdlib.h>
+
+void generate(int n) {
+
+  printf("{ \"inp\":\n" );
+  for(int i=0;i<n;i++) {
+    char c = (i==0)?'[':',';
+    printf("%c%d",c,i+1);
+    if ((i%10)==9) { printf("\n"); }
+  }
+  printf("]\n");
+  printf("}\n");
+
+}
+
+int main( int argc, char *argv[] ) {
+  
+  int nElements = 1;
+  switch(argc) {
+
+    case 2:
+      nElements = atoi(argv[1]);
+      generate(nElements);
+      break;
+
+    default:
+      printf("usage:\n");
+      printf("$ ./generate_input <number_of_field_elements>:\n");
+      exit(-1);
+      break;
+
+  }
+}
+
diff --git a/hash/snark/bench/Poseidon2/hash_sponge.circom.template b/hash/snark/bench/Poseidon2/hash_sponge.circom.template
new file mode 100644
index 0000000..f8e8b28
--- /dev/null
+++ b/hash/snark/bench/Poseidon2/hash_sponge.circom.template
@@ -0,0 +1,5 @@
+pragma circom 2.0.0;
+
+include "../../../external/hash-circuits/circuits/poseidon2/poseidon2_hash.circom";
+
+component main {public [inp]} = Poseidon2_hash( ZKBENCH_INPUT_SIZE );
diff --git a/hash/snark/bench/Poseidon2/run.sh b/hash/snark/bench/Poseidon2/run.sh
new file mode 100755
index 0000000..4df2999
--- /dev/null
+++ b/hash/snark/bench/Poseidon2/run.sh
@@ -0,0 +1,11 @@
+#!/bin/bash
+
+ORIG=`pwd`
+
+cd build
+
+NAME="hash_sponge"
+echo "generating proof with snarkjs"
+snarkjs groth16 prove ${NAME}_prover.zkey ${NAME}_witness.wtns ${NAME}_proof.json ${NAME}_public.json
+
+cd $ORIG
diff --git a/hash/snark/bench/Poseidon2/setup.sh b/hash/snark/bench/Poseidon2/setup.sh
new file mode 100755
index 0000000..c23b51d
--- /dev/null
+++ b/hash/snark/bench/Poseidon2/setup.sh
@@ -0,0 +1,24 @@
+#!/bin/bash
+
+ORIG=`pwd`
+ROOT="${ORIG}/../../../../"
+
+cd build
+
+echo "generating input..."
+./generate_input $ZKBENCH_INPUT_SIZE >input.json
+
+echo "generating witness..."
+NAME="hash_sponge"
+cd ${NAME}_js
+node generate_witness.js ${NAME}.wasm ../input.json ../${NAME}_witness.wtns || { echo "witness gen failed"; exit 101; }
+cd ..
+
+echo "circuit-specific ceremony..."
+snarkjs groth16 setup ${NAME}.r1cs ${ROOT}/ceremony/ceremony.ptau ${NAME}_0000.zkey
+echo "some_entropy" | snarkjs zkey contribute ${NAME}_0000.zkey ${NAME}_0001.zkey --name="1st Contributor Name"
+rm ${NAME}_0000.zkey
+mv ${NAME}_0001.zkey ${NAME}_prover.zkey
+snarkjs zkey export verificationkey ${NAME}_prover.zkey ${NAME}_verification_key.json
+
+cd $ORIG
diff --git a/hash/snark/external/hash-circuits b/hash/snark/external/hash-circuits
new file mode 160000
index 0000000..bf6cca3
--- /dev/null
+++ b/hash/snark/external/hash-circuits
@@ -0,0 +1 @@
+Subproject commit bf6cca380547ca905ca0615cfdb6c49660e441a2