diff --git a/Cargo.lock b/Cargo.lock
index f1b68e2ef..73f395cc9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -924,11 +924,11 @@ dependencies = [
  "log",
  "mozak-circuits-derive",
  "mozak-runner",
- "mozak-sdk",
  "plonky2",
  "plonky2_maybe_rayon",
  "proptest",
  "rand",
+ "sdk-core-types",
  "serde",
  "serde_json",
  "starky",
@@ -1022,9 +1022,9 @@ dependencies = [
  "log",
  "mimalloc",
  "mozak-examples",
- "mozak-sdk",
  "plonky2",
  "proptest",
+ "sdk-core-types",
  "serde",
  "serde_json",
  "test-case",
@@ -1042,6 +1042,7 @@ dependencies = [
  "rand_chacha",
  "rkyv",
  "rkyv_derive",
+ "sdk-core-types",
  "serde",
  "serde-hex",
  "serde_json",
@@ -1533,6 +1534,10 @@ dependencies = [
  "winapi-util",
 ]
 
+[[package]]
+name = "sdk-core-types"
+version = "0.1.0"
+
 [[package]]
 name = "serde"
 version = "1.0.201"
diff --git a/Cargo.toml b/Cargo.toml
index c8a0014ba..42fe9bfd0 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -19,6 +19,7 @@ exclude = ["sdk"]
 members = [
   "circuits",
   "cli",
+  "sdk-core-types",
   "examples-builder",
   "expr",
   "node",
diff --git a/circuits/Cargo.toml b/circuits/Cargo.toml
index 74efdb20d..cf5dfdc68 100644
--- a/circuits/Cargo.toml
+++ b/circuits/Cargo.toml
@@ -19,9 +19,9 @@ itertools = "0.12"
 log = "0.4"
 mozak-circuits-derive = { path = "./derive" }
 mozak-runner = { path = "../runner" }
-mozak-sdk = { path = "../sdk" }
 plonky2 = { workspace = true, default-features = false }
 plonky2_maybe_rayon = { workspace = true, default-features = false }
+sdk-core-types = { path = "../sdk-core-types" }
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 starky = { workspace = true, default-features = false, features = ["std"] }
diff --git a/circuits/src/cpu/ecall.rs b/circuits/src/cpu/ecall.rs
index ae1a2b7cc..54d5cb2c6 100644
--- a/circuits/src/cpu/ecall.rs
+++ b/circuits/src/cpu/ecall.rs
@@ -3,7 +3,7 @@
 
 use expr::Expr;
 use itertools::izip;
-use mozak_sdk::core::ecall;
+use sdk_core_types::ecall_id;
 
 use super::columns::CpuState;
 use crate::expr::ConstraintBuilder;
@@ -51,7 +51,7 @@ pub(crate) fn halt_constraints<'a, P: Copy>(
     // anywhere else.
     // Enable only for halt !!!
     cb.transition(lv.is_halt * (lv.inst.ops.ecall + nv.is_running - 1));
-    cb.always(lv.is_halt * (lv.op1_value - i64::from(ecall::HALT)));
+    cb.always(lv.is_halt * (lv.op1_value - i64::from(ecall_id::HALT)));
 
     // We also need to make sure that the program counter is not changed by the
     // 'halt' system call.
@@ -77,25 +77,25 @@ pub(crate) fn storage_device_constraints<'a, P: Copy>(
     lv: &CpuState<Expr<'a, P>>,
     cb: &mut ConstraintBuilder<Expr<'a, P>>,
 ) {
-    cb.always(lv.is_private_tape * (lv.op1_value - i64::from(ecall::PRIVATE_TAPE)));
-    cb.always(lv.is_public_tape * (lv.op1_value - i64::from(ecall::PUBLIC_TAPE)));
-    cb.always(lv.is_call_tape * (lv.op1_value - i64::from(ecall::CALL_TAPE)));
-    cb.always(lv.is_event_tape * (lv.op1_value - i64::from(ecall::EVENT_TAPE)));
+    cb.always(lv.is_private_tape * (lv.op1_value - i64::from(ecall_id::PRIVATE_TAPE)));
+    cb.always(lv.is_public_tape * (lv.op1_value - i64::from(ecall_id::PUBLIC_TAPE)));
+    cb.always(lv.is_call_tape * (lv.op1_value - i64::from(ecall_id::CALL_TAPE)));
+    cb.always(lv.is_event_tape * (lv.op1_value - i64::from(ecall_id::EVENT_TAPE)));
     cb.always(
-        lv.is_events_commitment_tape * (lv.op1_value - i64::from(ecall::EVENTS_COMMITMENT_TAPE)),
+        lv.is_events_commitment_tape * (lv.op1_value - i64::from(ecall_id::EVENTS_COMMITMENT_TAPE)),
     );
     cb.always(
         lv.is_cast_list_commitment_tape
-            * (lv.op1_value - i64::from(ecall::CAST_LIST_COMMITMENT_TAPE)),
+            * (lv.op1_value - i64::from(ecall_id::CAST_LIST_COMMITMENT_TAPE)),
     );
-    cb.always(lv.is_self_prog_id_tape * (lv.op1_value - i64::from(ecall::SELF_PROG_ID_TAPE)));
+    cb.always(lv.is_self_prog_id_tape * (lv.op1_value - i64::from(ecall_id::SELF_PROG_ID_TAPE)));
 }
 
 pub(crate) fn poseidon2_constraints<'a, P: Copy>(
     lv: &CpuState<Expr<'a, P>>,
     cb: &mut ConstraintBuilder<Expr<'a, P>>,
 ) {
-    cb.always(lv.is_poseidon2 * (lv.op1_value - i64::from(ecall::POSEIDON2)));
+    cb.always(lv.is_poseidon2 * (lv.op1_value - i64::from(ecall_id::POSEIDON2)));
 }
 
 // We are already testing ecall halt with our coda of every `code::execute`.
diff --git a/circuits/src/generation/cpu.rs b/circuits/src/generation/cpu.rs
index 8e1719b07..1d8a0d9f7 100644
--- a/circuits/src/generation/cpu.rs
+++ b/circuits/src/generation/cpu.rs
@@ -1,11 +1,11 @@
 use expr::{Evaluator, ExprBuilder};
 use itertools::{chain, Itertools};
 use mozak_runner::instruction::{Instruction, Op};
+use mozak_runner::reg_abi::REG_A0;
 use mozak_runner::state::{Aux, State, StorageDeviceEntry, StorageDeviceOpcode};
 use mozak_runner::vm::{ExecutionRecord, Row};
-use mozak_sdk::core::ecall;
-use mozak_sdk::core::reg_abi::REG_A0;
 use plonky2::hash::hash_types::RichField;
+use sdk_core_types::ecall_id;
 
 use crate::bitshift::columns::Bitshift;
 use crate::cpu::columns as cpu_cols;
@@ -110,7 +110,7 @@ pub fn generate_cpu_trace<F: RichField>(record: &ExecutionRecord<F>) -> Vec<CpuS
             )),
             is_halt: F::from_bool(matches!(
                 (inst.op, state.registers[usize::from(REG_A0)]),
-                (Op::ECALL, ecall::HALT)
+                (Op::ECALL, ecall_id::HALT)
             )),
             ..CpuState::default()
         };
diff --git a/circuits/src/poseidon2_sponge/columns.rs b/circuits/src/poseidon2_sponge/columns.rs
index b7250cf6e..ecc9c2b63 100644
--- a/circuits/src/poseidon2_sponge/columns.rs
+++ b/circuits/src/poseidon2_sponge/columns.rs
@@ -1,7 +1,7 @@
 use core::ops::Add;
 
 use itertools::izip;
-use mozak_sdk::core::reg_abi::{REG_A1, REG_A2, REG_A3};
+use mozak_runner::reg_abi::{REG_A1, REG_A2, REG_A3};
 use plonky2::field::goldilocks_field::GoldilocksField;
 use plonky2::hash::hash_types::NUM_HASH_OUT_ELTS;
 use plonky2::hash::hashing::PlonkyPermutation;
diff --git a/circuits/src/stark/recursive_verifier.rs b/circuits/src/stark/recursive_verifier.rs
index a7c76b131..2ee5009ee 100644
--- a/circuits/src/stark/recursive_verifier.rs
+++ b/circuits/src/stark/recursive_verifier.rs
@@ -6,7 +6,6 @@ use std::marker::PhantomData;
 use anyhow::Result;
 use itertools::{zip_eq, Itertools};
 use log::info;
-use mozak_sdk::core::constants::DIGEST_BYTES;
 use plonky2::field::extension::Extendable;
 use plonky2::field::types::Field;
 use plonky2::fri::witness_util::set_fri_proof_target;
@@ -22,6 +21,7 @@ use plonky2::plonk::config::{AlgebraicHasher, GenericConfig};
 use plonky2::plonk::proof::{ProofWithPublicInputs, ProofWithPublicInputsTarget};
 use plonky2::util::reducing::ReducingFactorTarget;
 use plonky2::with_context;
+use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
 use starky::config::StarkConfig;
 use starky::constraint_consumer::RecursiveConstraintConsumer;
 use starky::evaluation_frame::StarkEvaluationFrame;
@@ -654,12 +654,12 @@ mod tests {
     use log::info;
     use mozak_runner::code;
     use mozak_runner::instruction::{Args, Instruction, Op};
-    use mozak_sdk::core::constants::DIGEST_BYTES;
     use plonky2::field::goldilocks_field::GoldilocksField;
     use plonky2::iop::witness::{PartialWitness, WitnessWrite};
     use plonky2::plonk::circuit_builder::CircuitBuilder;
     use plonky2::plonk::circuit_data::CircuitConfig;
     use plonky2::util::timing::TimingTree;
+    use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
     use starky::config::StarkConfig;
 
     use crate::stark::mozak_stark::{MozakStark, PublicInputs};
diff --git a/circuits/src/storage_device/columns.rs b/circuits/src/storage_device/columns.rs
index 281531b11..83ee4be59 100644
--- a/circuits/src/storage_device/columns.rs
+++ b/circuits/src/storage_device/columns.rs
@@ -1,7 +1,7 @@
 use core::ops::Add;
 
-use mozak_sdk::core::constants::DIGEST_BYTES;
-use mozak_sdk::core::reg_abi::REG_A1;
+use mozak_runner::reg_abi::REG_A1;
+use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
 
 use crate::columns_view::{columns_view_impl, make_col_map, NumberOfColumns};
 use crate::cross_table_lookup::{Column, ColumnWithTypedInput};
diff --git a/circuits/src/storage_device/stark.rs b/circuits/src/storage_device/stark.rs
index 6ed9de221..06c5ff25d 100644
--- a/circuits/src/storage_device/stark.rs
+++ b/circuits/src/storage_device/stark.rs
@@ -118,14 +118,14 @@ mod tests {
     use mozak_runner::code::execute_code_with_ro_memory;
     use mozak_runner::decode::ECALL;
     use mozak_runner::instruction::{Args, Instruction, Op};
+    use mozak_runner::reg_abi::{REG_A0, REG_A1, REG_A2};
     use mozak_runner::state::RawTapes;
     use mozak_runner::test_utils::{u32_extra, u8_extra};
-    use mozak_sdk::core::constants::DIGEST_BYTES;
-    use mozak_sdk::core::ecall::{self};
-    use mozak_sdk::core::reg_abi::{REG_A0, REG_A1, REG_A2};
     use plonky2::plonk::config::Poseidon2GoldilocksConfig;
     use proptest::prelude::ProptestConfig;
     use proptest::proptest;
+    use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
+    use sdk_core_types::ecall_id;
     use starky::stark_testing::test_stark_circuit_constraints;
 
     use crate::stark::mozak_stark::MozakStark;
@@ -139,7 +139,7 @@ mod tests {
             &[],
             &[(address, 0)],
             &[
-                (REG_A0, ecall::PRIVATE_TAPE),
+                (REG_A0, ecall_id::PRIVATE_TAPE),
                 (REG_A1, address), // A1 - address
                 (REG_A2, 0),       // A2 - size
             ],
@@ -155,7 +155,7 @@ mod tests {
             &[],
             &[(address, 0)],
             &[
-                (REG_A0, ecall::PUBLIC_TAPE),
+                (REG_A0, ecall_id::PUBLIC_TAPE),
                 (REG_A1, address), // A1 - address
                 (REG_A2, 0),       // A2 - size
             ],
@@ -171,7 +171,7 @@ mod tests {
             &[],
             &[(address, 0)],
             &[
-                (REG_A0, ecall::CALL_TAPE),
+                (REG_A0, ecall_id::CALL_TAPE),
                 (REG_A1, address), // A1 - address
                 (REG_A2, 0),       // A2 - size
             ],
@@ -187,7 +187,7 @@ mod tests {
             &[],
             &[(address, 0)],
             &[
-                (REG_A0, ecall::EVENT_TAPE),
+                (REG_A0, ecall_id::EVENT_TAPE),
                 (REG_A1, address), // A1 - address
                 (REG_A2, 0),       // A2 - size
             ],
@@ -203,7 +203,7 @@ mod tests {
             &[],
             &[(address, 0)],
             &[
-                (REG_A0, ecall::PRIVATE_TAPE),
+                (REG_A0, ecall_id::PRIVATE_TAPE),
                 (REG_A1, address), // A1 - address
                 (REG_A2, 1),       // A2 - size
             ],
@@ -228,7 +228,7 @@ mod tests {
             &[],
             &[(address, 0)],
             &[
-                (REG_A0, ecall::PUBLIC_TAPE),
+                (REG_A0, ecall_id::PUBLIC_TAPE),
                 (REG_A1, address), // A1 - address
                 (REG_A2, 1),       // A2 - size
             ],
@@ -254,7 +254,7 @@ mod tests {
             &[],
             &[(address, 0)],
             &[
-                (REG_A0, ecall::CALL_TAPE),
+                (REG_A0, ecall_id::CALL_TAPE),
                 (REG_A1, address), // A1 - address
                 (REG_A2, 1),       // A2 - size
             ],
@@ -278,7 +278,7 @@ mod tests {
             &[],
             &[(address, 0)],
             &[
-                (REG_A0, ecall::EVENT_TAPE),
+                (REG_A0, ecall_id::EVENT_TAPE),
                 (REG_A1, address), // A1 - address
                 (REG_A2, 1),       // A2 - size
             ],
@@ -307,7 +307,7 @@ mod tests {
                 .map(|i| (address.wrapping_add(u32::try_from(i).unwrap()), 0_u8))
                 .collect_vec(),
             &[
-                (REG_A0, ecall::EVENTS_COMMITMENT_TAPE),
+                (REG_A0, ecall_id::EVENTS_COMMITMENT_TAPE),
                 (REG_A1, address),                              // A1 - address
                 (REG_A2, u32::try_from(DIGEST_BYTES).unwrap()), // A2 - size
             ],
@@ -338,7 +338,7 @@ mod tests {
                 .map(|i| (address.wrapping_add(u32::try_from(i).unwrap()), 0_u8))
                 .collect_vec(),
             &[
-                (REG_A0, ecall::CAST_LIST_COMMITMENT_TAPE),
+                (REG_A0, ecall_id::CAST_LIST_COMMITMENT_TAPE),
                 (REG_A1, address),                              // A1 - address
                 (REG_A2, u32::try_from(DIGEST_BYTES).unwrap()), // A2 - size
             ],
@@ -382,7 +382,7 @@ mod tests {
                     op: Op::ADD,
                     args: Args {
                         rd: REG_A0,
-                        imm: ecall::PRIVATE_TAPE,
+                        imm: ecall_id::PRIVATE_TAPE,
                         ..Args::default()
                     },
                 },
diff --git a/circuits/src/tape_commitments/columns.rs b/circuits/src/tape_commitments/columns.rs
index 0b63820e8..8287a9af2 100644
--- a/circuits/src/tape_commitments/columns.rs
+++ b/circuits/src/tape_commitments/columns.rs
@@ -1,4 +1,4 @@
-use mozak_sdk::core::constants::DIGEST_BYTES;
+use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
 
 use crate::columns_view::{columns_view_impl, make_col_map};
 use crate::linear_combination::Column;
diff --git a/circuits/src/tape_commitments/stark.rs b/circuits/src/tape_commitments/stark.rs
index 3c55b7581..2b24fee98 100644
--- a/circuits/src/tape_commitments/stark.rs
+++ b/circuits/src/tape_commitments/stark.rs
@@ -86,15 +86,15 @@ mod tests {
     use mozak_runner::code;
     use mozak_runner::decode::ECALL;
     use mozak_runner::instruction::{Args, Instruction, Op};
+    use mozak_runner::reg_abi::{REG_A0, REG_A1, REG_A2};
     use mozak_runner::state::RawTapes;
-    use mozak_sdk::core::constants::DIGEST_BYTES;
-    use mozak_sdk::core::ecall::{self};
-    use mozak_sdk::core::reg_abi::{REG_A0, REG_A1, REG_A2};
     use plonky2::field::types::Field;
     use plonky2::plonk::circuit_data::CircuitConfig;
     use plonky2::plonk::config::{GenericConfig, Poseidon2GoldilocksConfig};
     use plonky2::util::timing::TimingTree;
     use rand::Rng;
+    use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
+    use sdk_core_types::ecall_id;
     use starky::config::StarkConfig;
     use starky::stark_testing::test_stark_circuit_constraints;
 
@@ -147,12 +147,12 @@ mod tests {
             ]
         }
         let code_ecall_cast_list_commitment_tape = read_ecall_code(
-            ecall::CAST_LIST_COMMITMENT_TAPE,
+            ecall_id::CAST_LIST_COMMITMENT_TAPE,
             CAST_LIST_COMMITMENT_ADDRESS,
             DIGEST_BYTES,
         );
         let code_ecall_events_commitment_tape = read_ecall_code(
-            ecall::EVENTS_COMMITMENT_TAPE,
+            ecall_id::EVENTS_COMMITMENT_TAPE,
             EVENTS_COMMITMENT_ADDRESS,
             DIGEST_BYTES,
         );
diff --git a/circuits/src/test_utils.rs b/circuits/src/test_utils.rs
index 002f0b92f..31ac0d1b7 100644
--- a/circuits/src/test_utils.rs
+++ b/circuits/src/test_utils.rs
@@ -6,9 +6,8 @@ use mozak_runner::code;
 use mozak_runner::decode::ECALL;
 use mozak_runner::elf::Program;
 use mozak_runner::instruction::{Args, Instruction, Op};
+use mozak_runner::reg_abi::{REG_A0, REG_A1, REG_A2, REG_A3};
 use mozak_runner::vm::ExecutionRecord;
-use mozak_sdk::core::ecall;
-use mozak_sdk::core::reg_abi::{REG_A0, REG_A1, REG_A2, REG_A3};
 use plonky2::field::goldilocks_field::GoldilocksField;
 use plonky2::field::types::Field;
 use plonky2::fri::FriConfig;
@@ -18,6 +17,7 @@ use plonky2::plonk::circuit_data::CircuitConfig;
 use plonky2::plonk::config::{GenericConfig, Hasher, Poseidon2GoldilocksConfig};
 use plonky2::util::log2_ceil;
 use plonky2::util::timing::TimingTree;
+use sdk_core_types::ecall_id;
 use starky::config::StarkConfig;
 use starky::prover::prove as prove_table;
 use starky::stark::Stark;
@@ -523,7 +523,7 @@ pub fn create_poseidon2_test(
                 op: Op::ADD,
                 args: Args {
                     rd: REG_A0,
-                    imm: ecall::POSEIDON2,
+                    imm: ecall_id::POSEIDON2,
                     ..Args::default()
                 },
             },
diff --git a/examples/Cargo.lock b/examples/Cargo.lock
index 7302d4a65..4c61212f2 100644
--- a/examples/Cargo.lock
+++ b/examples/Cargo.lock
@@ -287,6 +287,7 @@ dependencies = [
  "rand_chacha",
  "rkyv",
  "rkyv_derive",
+ "sdk-core-types",
  "serde",
  "serde-hex",
  "serde_json",
@@ -578,6 +579,10 @@ version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f3cb5ba0dc43242ce17de99c180e96db90b235b8a9fdc9543c96d2209116bd9f"
 
+[[package]]
+name = "sdk-core-types"
+version = "0.1.0"
+
 [[package]]
 name = "serde"
 version = "1.0.201"
diff --git a/runner/Cargo.toml b/runner/Cargo.toml
index 6005e1928..e8d5f1cbb 100644
--- a/runner/Cargo.toml
+++ b/runner/Cargo.toml
@@ -18,9 +18,9 @@ env_logger = { version = "0.11" }
 im = "15.1"
 itertools = "0.12"
 log = "0.4"
-mozak-sdk = { path = "../sdk" }
 plonky2 = { workspace = true, default-features = false }
 proptest = { version = "1.4", optional = true }
+sdk-core-types = { path = "../sdk-core-types" }
 serde = { version = "1.0", features = ["derive"] }
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
diff --git a/runner/src/code.rs b/runner/src/code.rs
index 691d25d9c..763e40547 100644
--- a/runner/src/code.rs
+++ b/runner/src/code.rs
@@ -4,8 +4,8 @@ use anyhow::Result;
 use derive_more::{Deref, IntoIterator};
 use im::hashmap::HashMap;
 use itertools::{chain, izip};
-use mozak_sdk::core::ecall;
 use plonky2::field::goldilocks_field::GoldilocksField;
+use sdk_core_types::ecall_id;
 use serde::{Deserialize, Serialize};
 
 use crate::decode::{decode_instruction, ECALL};
@@ -74,7 +74,7 @@ pub fn execute_code_with_ro_memory(
                     op: Op::ADD,
                     args: Args {
                         rd: 10,
-                        imm: ecall::HALT,
+                        imm: ecall_id::HALT,
                         ..Args::default()
                     },
                 },
diff --git a/runner/src/decode.rs b/runner/src/decode.rs
index b0c64c4c9..0c5538f45 100644
--- a/runner/src/decode.rs
+++ b/runner/src/decode.rs
@@ -1,8 +1,8 @@
 use bitfield::{bitfield, BitRange};
 use log::warn;
-use mozak_sdk::core::reg_abi::{REG_A0, REG_A1, REG_ZERO};
 
 use crate::instruction::{Args, DecodingError, Instruction, Op, NOP};
+use crate::reg_abi::{REG_A0, REG_A1, REG_ZERO};
 
 /// Extract a u32 that represents the immediate from segments with zeros right
 /// pads of specified length
diff --git a/runner/src/ecall.rs b/runner/src/ecall.rs
index 7efbac5fd..fd5cf919b 100644
--- a/runner/src/ecall.rs
+++ b/runner/src/ecall.rs
@@ -2,10 +2,28 @@
 
 use std::str::from_utf8;
 
-use mozak_sdk::core::ecall;
-use mozak_sdk::core::reg_abi::{REG_A0, REG_A1, REG_A2};
 use plonky2::hash::hash_types::RichField;
+use sdk_core_types::ecall_id;
 
+#[must_use]
+pub fn log<'a>(raw_id: u32) -> &'a str {
+    match raw_id {
+        ecall_id::HALT => "halt",
+        ecall_id::PANIC => "panic",
+        ecall_id::PUBLIC_TAPE => "ioread public tape",
+        ecall_id::POSEIDON2 => "poseidon2",
+        ecall_id::PRIVATE_TAPE => "ioread private tape",
+        ecall_id::CALL_TAPE => "ioread call tape",
+        ecall_id::EVENT_TAPE => "ioread event tape",
+        ecall_id::EVENTS_COMMITMENT_TAPE => "ioread events commitment tape",
+        ecall_id::CAST_LIST_COMMITMENT_TAPE => "ioread cast list commitment tape",
+        ecall_id::SELF_PROG_ID_TAPE => "self prog id tape",
+        ecall_id::VM_TRACE_LOG => "vm trace log",
+        _ => "",
+    }
+}
+
+use crate::reg_abi::{REG_A0, REG_A1, REG_A2};
 use crate::state::{read_bytes, Aux, State, StorageDeviceEntry, StorageDeviceOpcode};
 
 impl<F: RichField> State<F> {
@@ -134,23 +152,24 @@ impl<F: RichField> State<F> {
     pub fn ecall(self) -> (Aux<F>, Self) {
         log::trace!(
             "ecall '{}' at clk: {}",
-            ecall::log(self.get_register_value(REG_A0)),
+            log(self.get_register_value(REG_A0)),
             self.clk
         );
         match self.get_register_value(REG_A0) {
-            ecall::HALT => self.ecall_halt(),
-            ecall::PRIVATE_TAPE => self.ecall_read(StorageDeviceOpcode::StorePrivate),
-            ecall::PUBLIC_TAPE => self.ecall_read(StorageDeviceOpcode::StorePublic),
-            ecall::CALL_TAPE => self.ecall_read(StorageDeviceOpcode::StoreCallTape),
-            ecall::EVENT_TAPE => self.ecall_read(StorageDeviceOpcode::StoreEventTape),
-            ecall::EVENTS_COMMITMENT_TAPE =>
+            ecall_id::HALT => self.ecall_halt(),
+            ecall_id::PRIVATE_TAPE => self.ecall_read(StorageDeviceOpcode::StorePrivate),
+            ecall_id::PUBLIC_TAPE => self.ecall_read(StorageDeviceOpcode::StorePublic),
+            ecall_id::CALL_TAPE => self.ecall_read(StorageDeviceOpcode::StoreCallTape),
+            ecall_id::EVENT_TAPE => self.ecall_read(StorageDeviceOpcode::StoreEventTape),
+            ecall_id::EVENTS_COMMITMENT_TAPE =>
                 self.ecall_read(StorageDeviceOpcode::StoreEventsCommitmentTape),
-            ecall::CAST_LIST_COMMITMENT_TAPE =>
+            ecall_id::CAST_LIST_COMMITMENT_TAPE =>
                 self.ecall_read(StorageDeviceOpcode::StoreCastListCommitmentTape),
-            ecall::SELF_PROG_ID_TAPE => self.ecall_read(StorageDeviceOpcode::StoreSelfProgIdTape),
-            ecall::PANIC => self.ecall_panic(),
-            ecall::POSEIDON2 => self.ecall_poseidon2(),
-            ecall::VM_TRACE_LOG => self.ecall_trace_log(),
+            ecall_id::SELF_PROG_ID_TAPE =>
+                self.ecall_read(StorageDeviceOpcode::StoreSelfProgIdTape),
+            ecall_id::PANIC => self.ecall_panic(),
+            ecall_id::POSEIDON2 => self.ecall_poseidon2(),
+            ecall_id::VM_TRACE_LOG => self.ecall_trace_log(),
             _ => (Aux::default(), self.bump_pc()),
         }
     }
diff --git a/runner/src/lib.rs b/runner/src/lib.rs
index ea4279164..ae143603a 100644
--- a/runner/src/lib.rs
+++ b/runner/src/lib.rs
@@ -15,6 +15,7 @@ pub mod ecall;
 pub mod elf;
 pub mod instruction;
 pub mod poseidon2;
+pub mod reg_abi;
 pub mod state;
 #[cfg(any(feature = "test", test))]
 pub mod test_utils;
diff --git a/runner/src/poseidon2.rs b/runner/src/poseidon2.rs
index c87cfeadf..d132d3b23 100644
--- a/runner/src/poseidon2.rs
+++ b/runner/src/poseidon2.rs
@@ -1,13 +1,13 @@
 use std::iter::repeat;
 
 use itertools::{chain, izip};
-use mozak_sdk::core::constants::DIGEST_BYTES;
-use mozak_sdk::core::reg_abi::{REG_A1, REG_A2, REG_A3};
 use plonky2::hash::hash_types::{HashOut, RichField, NUM_HASH_OUT_ELTS};
 use plonky2::hash::hashing::PlonkyPermutation;
 use plonky2::hash::poseidon2::{Poseidon2Permutation, WIDTH};
 use plonky2::plonk::config::GenericHashOut;
+use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
 
+use crate::reg_abi::{REG_A1, REG_A2, REG_A3};
 use crate::state::{Aux, State};
 
 #[derive(Debug, Clone, Default)]
diff --git a/sdk/src/core/reg_abi.rs b/runner/src/reg_abi.rs
similarity index 100%
rename from sdk/src/core/reg_abi.rs
rename to runner/src/reg_abi.rs
diff --git a/runner/src/state.rs b/runner/src/state.rs
index d4362e9bd..5d306a74d 100644
--- a/runner/src/state.rs
+++ b/runner/src/state.rs
@@ -7,8 +7,8 @@ use derive_more::{Deref, Display};
 use im::hashmap::HashMap;
 use im::HashSet;
 use log::trace;
-use mozak_sdk::core::constants::DIGEST_BYTES;
 use plonky2::hash::hash_types::RichField;
+use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
 use serde::{Deserialize, Serialize};
 
 use crate::code::Code;
diff --git a/sdk-core-types/Cargo.toml b/sdk-core-types/Cargo.toml
new file mode 100644
index 000000000..cf352170e
--- /dev/null
+++ b/sdk-core-types/Cargo.toml
@@ -0,0 +1,10 @@
+[package]
+categories = ["development-tools", "zk"]
+description = "Provides types for used by sdk::core"
+edition = "2021"
+keywords = ["sdk", "types"]
+license = "Apache-2.0"
+name = "sdk-core-types"
+readme = "README.md"
+repository = "https://github.com/0xmozak/mozak-node/sdk-core-types"
+version = "0.1.0"
diff --git a/sdk-core-types/src/constants.rs b/sdk-core-types/src/constants.rs
new file mode 100644
index 000000000..ce361068f
--- /dev/null
+++ b/sdk-core-types/src/constants.rs
@@ -0,0 +1,8 @@
+pub mod poseidon2 {
+    /// The size of a `Poseidon2Hash` digest in bytes.
+    pub const DIGEST_BYTES: usize = 32;
+
+    /// `RATE` of `Poseidon2Permutation` we use
+    #[allow(dead_code)]
+    pub const RATE: usize = 8;
+}
diff --git a/sdk-core-types/src/ecall_id.rs b/sdk-core-types/src/ecall_id.rs
new file mode 100644
index 000000000..521d58878
--- /dev/null
+++ b/sdk-core-types/src/ecall_id.rs
@@ -0,0 +1,12 @@
+pub const HALT: u32 = 0;
+pub const PANIC: u32 = 1;
+pub const PRIVATE_TAPE: u32 = 2;
+pub const POSEIDON2: u32 = 3;
+pub const PUBLIC_TAPE: u32 = 4;
+pub const CALL_TAPE: u32 = 5;
+pub const EVENT_TAPE: u32 = 6;
+pub const EVENTS_COMMITMENT_TAPE: u32 = 7;
+pub const CAST_LIST_COMMITMENT_TAPE: u32 = 8;
+pub const SELF_PROG_ID_TAPE: u32 = 9;
+/// Syscall to output the VM trace log at `clk`. Useful for debugging.
+pub const VM_TRACE_LOG: u32 = 10;
diff --git a/sdk-core-types/src/lib.rs b/sdk-core-types/src/lib.rs
new file mode 100644
index 000000000..78e6fbe5a
--- /dev/null
+++ b/sdk-core-types/src/lib.rs
@@ -0,0 +1,4 @@
+#![cfg_attr(target_os = "mozakvm", no_std)]
+
+pub mod constants;
+pub mod ecall_id;
diff --git a/sdk/Cargo.lock b/sdk/Cargo.lock
index 9b6115790..14f2351a3 100644
--- a/sdk/Cargo.lock
+++ b/sdk/Cargo.lock
@@ -188,6 +188,7 @@ dependencies = [
  "rand_chacha",
  "rkyv",
  "rkyv_derive",
+ "sdk-core-types",
  "serde",
  "serde-hex",
  "serde_json",
@@ -455,6 +456,10 @@ version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f3cb5ba0dc43242ce17de99c180e96db90b235b8a9fdc9543c96d2209116bd9f"
 
+[[package]]
+name = "sdk-core-types"
+version = "0.1.0"
+
 [[package]]
 name = "serde"
 version = "1.0.201"
diff --git a/sdk/Cargo.toml b/sdk/Cargo.toml
index 640617f28..6065128b2 100644
--- a/sdk/Cargo.toml
+++ b/sdk/Cargo.toml
@@ -16,6 +16,7 @@ itertools = { version = "0.12", default-features = false }
 once_cell = { version = "1.19", default-features = false, features = ["race"] }
 rkyv = { version = "=0.8.0-alpha.1", default-features = false, features = ["pointer_width_32", "alloc"] }
 rkyv_derive = "=0.8.0-alpha.1"
+sdk-core-types = { path = "../sdk-core-types" }
 slice-group-by = { version = "0.3", default-features = false, features = ["nightly"] }
 
 [target.'cfg(not(target_os="mozakvm"))'.dependencies]
diff --git a/sdk/src/common/merkle.rs b/sdk/src/common/merkle.rs
index 8dd83cd34..f601c991d 100644
--- a/sdk/src/common/merkle.rs
+++ b/sdk/src/common/merkle.rs
@@ -48,10 +48,10 @@ fn merkleize_group(mut group: Vec<Poseidon2Hash>) -> Option<Poseidon2Hash> {
 #[cfg(test)]
 mod tests {
     use itertools::chain;
+    use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
 
     use crate::common::merkle::merkleize;
     use crate::common::types::Poseidon2Hash;
-    use crate::core::constants::DIGEST_BYTES;
     use crate::native::helpers::poseidon2_hash_no_pad;
 
     #[test]
diff --git a/sdk/src/common/system.rs b/sdk/src/common/system.rs
index 68a067cfc..d33e2ebf3 100644
--- a/sdk/src/common/system.rs
+++ b/sdk/src/common/system.rs
@@ -5,13 +5,13 @@ use {
     crate::common::types::{
         CanonicalOrderedTemporalHints, CrossProgramCall, Poseidon2Hash, ProgramIdentifier,
     },
-    crate::core::constants::DIGEST_BYTES,
     crate::core::ecall::{
         call_tape_read, event_tape_read, ioread_private, ioread_public, self_prog_id_tape_read,
     },
     core::ptr::slice_from_raw_parts,
     rkyv::rancor::{Panic, Strategy},
     rkyv::Deserialize,
+    sdk_core_types::constants::poseidon2::DIGEST_BYTES,
     std::collections::BTreeSet,
 };
 #[cfg(not(target_os = "mozakvm"))]
diff --git a/sdk/src/common/types/poseidon2hash.rs b/sdk/src/common/types/poseidon2hash.rs
index 31b4a00bd..14cce0cef 100644
--- a/sdk/src/common/types/poseidon2hash.rs
+++ b/sdk/src/common/types/poseidon2hash.rs
@@ -1,8 +1,7 @@
+use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
 #[cfg(not(target_os = "mozakvm"))]
 use serde_hex::{SerHex, StrictPfx};
 
-use crate::core::constants::DIGEST_BYTES;
-
 #[derive(
     Clone,
     Copy,
diff --git a/sdk/src/common/types/program_identifier.rs b/sdk/src/common/types/program_identifier.rs
index f67105ab3..f0a59f4f8 100644
--- a/sdk/src/common/types/program_identifier.rs
+++ b/sdk/src/common/types/program_identifier.rs
@@ -1,4 +1,5 @@
-use crate::core::constants::DIGEST_BYTES;
+use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
+
 #[cfg(target_os = "mozakvm")]
 use crate::mozakvm::helpers::poseidon2_hash_with_pad;
 #[cfg(not(target_os = "mozakvm"))]
diff --git a/sdk/src/core/ecall.rs b/sdk/src/core/ecall.rs
index 681bf7309..16179c622 100644
--- a/sdk/src/core/ecall.rs
+++ b/sdk/src/core/ecall.rs
@@ -2,45 +2,16 @@
 use core::arch::asm;
 
 #[cfg(target_os = "mozakvm")]
-use crate::core::constants::DIGEST_BYTES;
-
-pub const HALT: u32 = 0;
-pub const PANIC: u32 = 1;
-pub const PRIVATE_TAPE: u32 = 2;
-pub const POSEIDON2: u32 = 3;
-pub const PUBLIC_TAPE: u32 = 4;
-pub const CALL_TAPE: u32 = 5;
-pub const EVENT_TAPE: u32 = 6;
-pub const EVENTS_COMMITMENT_TAPE: u32 = 7;
-pub const CAST_LIST_COMMITMENT_TAPE: u32 = 8;
-pub const SELF_PROG_ID_TAPE: u32 = 9;
-/// Syscall to output the VM trace log at `clk`. Useful for debugging.
-pub const VM_TRACE_LOG: u32 = 10;
-
-#[must_use]
-pub fn log<'a>(raw_id: u32) -> &'a str {
-    match raw_id {
-        HALT => "halt",
-        PANIC => "panic",
-        PUBLIC_TAPE => "ioread public tape",
-        POSEIDON2 => "poseidon2",
-        PRIVATE_TAPE => "ioread private tape",
-        CALL_TAPE => "ioread call tape",
-        EVENT_TAPE => "ioread event tape",
-        EVENTS_COMMITMENT_TAPE => "ioread events commitment tape",
-        CAST_LIST_COMMITMENT_TAPE => "ioread cast list commitment tape",
-        SELF_PROG_ID_TAPE => "self prog id tape",
-        VM_TRACE_LOG => "vm trace log",
-        _ => "",
-    }
-}
+use sdk_core_types::constants::poseidon2::DIGEST_BYTES;
+#[cfg(target_os = "mozakvm")]
+use sdk_core_types::ecall_id;
 
 #[cfg(target_os = "mozakvm")]
 pub fn poseidon2(input_ptr: *const u8, input_len: usize, output_ptr: *mut u8) {
     unsafe {
         core::arch::asm!(
             "ecall",
-            in ("a0") POSEIDON2,
+            in ("a0") ecall_id::POSEIDON2,
             in ("a1") input_ptr,
             in ("a2") input_len,
             in ("a3") output_ptr,
@@ -53,7 +24,7 @@ pub fn ioread_private(buf_ptr: *mut u8, buf_len: usize) {
     unsafe {
         core::arch::asm!(
             "ecall",
-            in ("a0") PRIVATE_TAPE,
+            in ("a0") ecall_id::PRIVATE_TAPE,
             in ("a1") buf_ptr,
             in ("a2") buf_len,
         );
@@ -65,7 +36,7 @@ pub fn ioread_public(buf_ptr: *mut u8, buf_len: usize) {
     unsafe {
         core::arch::asm!(
         "ecall",
-        in ("a0") PUBLIC_TAPE,
+        in ("a0") ecall_id::PUBLIC_TAPE,
         in ("a1") buf_ptr,
         in ("a2") buf_len,
         );
@@ -77,7 +48,7 @@ pub fn call_tape_read(buf_ptr: *mut u8, buf_len: usize) {
     unsafe {
         core::arch::asm!(
         "ecall",
-        in ("a0") CALL_TAPE,
+        in ("a0") ecall_id::CALL_TAPE,
         in ("a1") buf_ptr,
         in ("a2") buf_len,
         );
@@ -89,7 +60,7 @@ pub fn event_tape_read(buf_ptr: *mut u8, buf_len: usize) {
     unsafe {
         core::arch::asm!(
         "ecall",
-        in ("a0") EVENT_TAPE,
+        in ("a0") ecall_id::EVENT_TAPE,
         in ("a1") buf_ptr,
         in ("a2") buf_len,
         );
@@ -101,7 +72,7 @@ pub fn events_commitment_tape_read(buf_ptr: *mut u8) {
     unsafe {
         core::arch::asm!(
         "ecall",
-        in ("a0") EVENTS_COMMITMENT_TAPE,
+        in ("a0") ecall_id::EVENTS_COMMITMENT_TAPE,
         in ("a1") buf_ptr,
         in ("a2") DIGEST_BYTES,
         );
@@ -113,7 +84,7 @@ pub fn cast_list_commitment_tape_read(buf_ptr: *mut u8) {
     unsafe {
         core::arch::asm!(
         "ecall",
-        in ("a0") CAST_LIST_COMMITMENT_TAPE,
+        in ("a0") ecall_id::CAST_LIST_COMMITMENT_TAPE,
         in ("a1") buf_ptr,
         in ("a2") DIGEST_BYTES,
         );
@@ -125,7 +96,7 @@ pub fn self_prog_id_tape_read(buf_ptr: *mut u8) {
     unsafe {
         core::arch::asm!(
         "ecall",
-        in ("a0") SELF_PROG_ID_TAPE,
+        in ("a0") ecall_id::SELF_PROG_ID_TAPE,
         in ("a1") buf_ptr,
         in ("a2") DIGEST_BYTES,
         );
@@ -137,7 +108,7 @@ pub fn panic(msg_ptr: *const u8, msg_len: usize) {
     unsafe {
         core::arch::asm!(
             "ecall",
-            in ("a0") PANIC,
+            in ("a0") ecall_id::PANIC,
             in ("a1") msg_len,
             in ("a2") msg_ptr,
         );
@@ -149,7 +120,7 @@ pub fn trace(msg_ptr: *const u8, msg_len: usize) {
     unsafe {
         core::arch::asm!(
             "ecall",
-            in ("a0") VM_TRACE_LOG,
+            in ("a0") ecall_id::VM_TRACE_LOG,
             in ("a1") msg_len,
             in ("a2") msg_ptr,
         );
@@ -161,7 +132,7 @@ pub fn halt(output: u8) {
     unsafe {
         asm!(
             "ecall",
-            in ("a0") HALT,
+            in ("a0") ecall_id::HALT,
             in ("a1") output,
         );
         unreachable!();
diff --git a/sdk/src/core/mod.rs b/sdk/src/core/mod.rs
index cc419024c..4e71ead04 100644
--- a/sdk/src/core/mod.rs
+++ b/sdk/src/core/mod.rs
@@ -2,16 +2,6 @@
 mod alloc;
 pub mod ecall;
 pub mod env;
-pub mod reg_abi;
-
-pub mod constants {
-    /// The size of a `Poseidon2Hash` digest in bytes.
-    pub const DIGEST_BYTES: usize = 32;
-
-    /// `RATE` of `Poseidon2Permutation` we use
-    #[allow(dead_code)]
-    pub const RATE: usize = 8;
-}
 
 #[macro_export]
 macro_rules! entry {
diff --git a/sdk/src/mozakvm/helpers.rs b/sdk/src/mozakvm/helpers.rs
index fd8bd432f..57839d9f5 100644
--- a/sdk/src/mozakvm/helpers.rs
+++ b/sdk/src/mozakvm/helpers.rs
@@ -1,7 +1,8 @@
 // This file contains code snippets used in mozakvm execution
 
+use sdk_core_types::constants::poseidon2::{DIGEST_BYTES, RATE};
+
 use crate::common::types::Poseidon2Hash;
-use crate::core::constants::{DIGEST_BYTES, RATE};
 
 /// Hashes the input slice to `Poseidon2Hash` after padding.
 /// We use the well known "Bit padding scheme".
diff --git a/sdk/src/mozakvm/inputtape.rs b/sdk/src/mozakvm/inputtape.rs
index 17b979f4d..3882aacec 100644
--- a/sdk/src/mozakvm/inputtape.rs
+++ b/sdk/src/mozakvm/inputtape.rs
@@ -1,6 +1,6 @@
 use core::ops::{Deref, DerefMut};
 
-use crate::core::ecall;
+use sdk_core_types::ecall_id;
 
 #[derive(Default, Clone)]
 pub struct RandomAccessEcallTape {
@@ -111,7 +111,7 @@ pub struct PublicInputTape(RandomAccessEcallTape);
 impl Default for PrivateInputTape {
     fn default() -> Self {
         Self(RandomAccessEcallTape {
-            ecall_id: ecall::PRIVATE_TAPE,
+            ecall_id: ecall_id::PRIVATE_TAPE,
             read_offset: 0,
             size_hint: 0,
             internal_buf: vec![],
@@ -123,7 +123,7 @@ impl PrivateInputTape {
     /// Creates a new `PrivateInputTape` with a given `size_hint`.
     pub fn with_size_hint(size_hint: usize) -> Self {
         Self(RandomAccessEcallTape {
-            ecall_id: ecall::PRIVATE_TAPE,
+            ecall_id: ecall_id::PRIVATE_TAPE,
             read_offset: 0,
             size_hint,
             internal_buf: vec![],
@@ -134,7 +134,7 @@ impl PrivateInputTape {
 impl Default for PublicInputTape {
     fn default() -> Self {
         Self(RandomAccessEcallTape {
-            ecall_id: ecall::PUBLIC_TAPE,
+            ecall_id: ecall_id::PUBLIC_TAPE,
             read_offset: 0,
             size_hint: 0,
             internal_buf: vec![],
@@ -146,7 +146,7 @@ impl PublicInputTape {
     /// Creates a new `PublicInputTape` with a given `size_hint`.
     pub fn with_size_hint(size_hint: usize) -> Self {
         Self(RandomAccessEcallTape {
-            ecall_id: ecall::PUBLIC_TAPE,
+            ecall_id: ecall_id::PUBLIC_TAPE,
             read_offset: 0,
             size_hint,
             internal_buf: vec![],
diff --git a/sdk/src/native/helpers.rs b/sdk/src/native/helpers.rs
index 864bed100..b6888515c 100644
--- a/sdk/src/native/helpers.rs
+++ b/sdk/src/native/helpers.rs
@@ -5,9 +5,9 @@ use plonky2::field::goldilocks_field::GoldilocksField;
 use plonky2::field::types::Field;
 use plonky2::hash::poseidon2::Poseidon2Hash as Plonky2Poseidon2Hash;
 use plonky2::plonk::config::{GenericHashOut, Hasher};
+use sdk_core_types::constants::poseidon2::RATE;
 
 use crate::common::types::Poseidon2Hash;
-use crate::core::constants::RATE;
 
 /// Hashes the input slice to `Poseidon2Hash` after padding.
 /// We use the well known "Bit padding scheme".