diff --git a/src/air/public_input.cairo b/src/air/public_input.cairo
index db824ffc1..fcb221439 100644
--- a/src/air/public_input.cairo
+++ b/src/air/public_input.cairo
@@ -86,7 +86,21 @@ impl PublicInputImpl of PublicInputTrait {
 
         let program_end_pc = initial_fp - 2;
         let program_len = program_end_pc - initial_pc;
-        memory.extract_range(initial_pc, program_len);
+        let program = memory.extract_range(initial_pc, program_len);
+
+        assert(
+            *program[0] == 0x40780017fff7fff, 'Invalid program'
+        ); // Instruction: ap += N_BUILTINS.
+        assert(*program[1] == builtins.len().into(), 'Invalid program');
+        assert(*program[2] == 0x1104800180018000, 'Invalid program'); // Instruction: call rel ?.
+        assert(*program[4] == 0x10780017fff7fff, 'Invalid program'); // Instruction: jmp rel 0.
+        assert(*program[5] == 0x0, 'Invalid program');
+
+        // TODO hash program
+        let program_hash = 0;
+
+        // 2. Execution segment
+        // 2.1 Initial_fp, initial_pc
 
         (0, 0)
     }
diff --git a/src/common.cairo b/src/common.cairo
index cf165c02e..6eef1ade9 100644
--- a/src/common.cairo
+++ b/src/common.cairo
@@ -7,6 +7,7 @@ mod math;
 mod array_print;
 mod array_extend;
 mod consts;
+mod hash;
 
 #[cfg(test)]
 mod tests;
diff --git a/src/common/hash.cairo b/src/common/hash.cairo
new file mode 100644
index 000000000..8981c23a7
--- /dev/null
+++ b/src/common/hash.cairo
@@ -0,0 +1,15 @@
+use pedersen::PedersenTrait;
+use hash::HashStateTrait;
+
+fn hash_felts(s: Span<felt252>) -> felt252 {
+    let mut hash_state = PedersenTrait::new(0);
+    let mut i = 0;
+
+    loop {
+        if i == s.len() {
+            break hash_state.finalize();
+        }
+
+        hash_state.update(*s.at(i));
+    }
+}