diff --git a/crates/leanVm/src/types/instruction.rs b/crates/leanVm/src/types/instruction.rs
index e69de29b..1ecd2e50 100644
--- a/crates/leanVm/src/types/instruction.rs
+++ b/crates/leanVm/src/types/instruction.rs
@@ -0,0 +1,91 @@
+use p3_koala_bear::KoalaBear;
+use std::collections::BTreeMap;
+
+type Label = String;
+type F = KoalaBear;
+
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct Bytecode {
+    pub instructions: Vec<Instruction>,
+    pub hints: BTreeMap<usize, Vec<Hint>>, // pc -> hints
+    pub public_input_start: usize,
+    pub ending_pc: usize,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum MemOrConstant {
+    Constant(F),
+    MemoryAfterFp { shift: usize }, // m[fp + shift]
+}
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum MemOrFpOrConstant {
+    MemoryAfterFp { shift: usize }, // m[fp + shift]
+    Fp,
+    Constant(F),
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum MemOrFp {
+    MemoryAfterFp { shift: usize }, // m[fp + shift]
+    Fp,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum Operation {
+    Add,
+    Mul,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum Instruction {
+    Computation {
+        operation: Operation,
+        arg_a: MemOrConstant,
+        arg_b: MemOrFp,
+        res: MemOrConstant,
+    },
+    Deref {
+        shift_0: usize,
+        shift_1: usize,
+        res: MemOrFpOrConstant,
+    }, // res = m[m[fp + shift_0] + shift_1]
+    JumpIfNotZero {
+        condition: MemOrConstant,
+        dest: MemOrConstant,
+        updated_fp: MemOrFp,
+    },
+    Poseidon2_16 {
+        shift: usize,
+    }, /*
+        Read 4 vectorized pointers from stack:
+        Poseidon2(m[8 * m[fp + shift]] .. 8 * (1 + m[fp + shift])] | m[8 * m[fp + shift + 1]] .. 8 * (1 + m[fp + shift + 1])])
+        = m[8 * m[fp + shift + 2]] .. 8 * (1 + m[fp + shift + 2])] | m[8 * m[fp + shift + 3]] .. 8 * (1 + m[fp + shift + 3])]
+       */
+    Poseidon2_24 {
+        shift: usize,
+    }, // same as above, but with 24 field elements
+    ExtensionMul {
+        args: [usize; 3], // offset after fp
+    },
+}
+
+/// Hints does not appear in the verified bytecode, but are useful during execution
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum Hint {
+    RequestMemory {
+        offset: usize, // the pointer to the allocated memory range will be stored at m[fp + offset]
+        size: MemOrConstant,
+        /// if vectorized == true, the start of the allocated memory will be aligned to 8 field elements
+        /// m[8X...] and we set m[fp + offset] = X
+        vectorized: bool,
+    },
+    DecomposeBits {
+        res_offset: usize, // m[fp + res_offset..fp + res_offset + 31] will contain the decomposed bits
+        to_decompose: MemOrConstant,
+    },
+    // Debug purpose
+    Print {
+        line_info: String,
+        content: Vec<MemOrConstant>,
+    },
+}