diff --git a/Cargo.toml b/Cargo.toml
index 16ef6e1..af287fc 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -43,6 +43,7 @@ clippy.absolute-paths                = "allow"
 clippy.min-ident-chars               = "allow"
 clippy.indexing-slicing              = "allow"
 clippy.little-endian-bytes           = "allow"
+clippy.self-named-module-files       = "allow"
 
 [workspace.lints.rust]
 unsafe_code = "deny"
diff --git a/fuzz_props/src/invariants.rs b/fuzz_props/src/invariants.rs
index a233406..b4d92bc 100644
--- a/fuzz_props/src/invariants.rs
+++ b/fuzz_props/src/invariants.rs
@@ -337,187 +337,3 @@ pub fn assert_invariants(ctx: &InvariantCtx<'_>) {
         }
     }
 }
-
-// ── Unit tests ────────────────────────────────────────────────────────────────
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use nssa::V03State;
-
-    fn make_empty_state() -> V03State {
-        V03State::new_with_genesis_accounts(&[], vec![], 0)
-    }
-
-    fn make_empty_snapshot() -> BalanceSnapshot {
-        BalanceSnapshot(std::collections::HashMap::new())
-    }
-
-    fn make_empty_nonce_snapshot() -> NonceSnapshot {
-        NonceSnapshot(std::collections::HashMap::new())
-    }
-
-    #[test]
-    fn invariant_state_isolation_on_failure_does_not_panic_on_error() {
-        let state = make_empty_state();
-        let ctx = InvariantCtx {
-            state_before: &state,
-            state_after: &state,
-            execution_succeeded: false,
-            balances_before: make_empty_snapshot(),
-            nonces_before: make_empty_nonce_snapshot(),
-        };
-        assert_invariants(&ctx);
-    }
-
-    #[test]
-    fn invariant_replay_rejection_does_not_panic() {
-        let state = make_empty_state();
-        let ctx = InvariantCtx {
-            state_before: &state,
-            state_after: &state,
-            execution_succeeded: true,
-            balances_before: make_empty_snapshot(),
-            nonces_before: make_empty_nonce_snapshot(),
-        };
-        assert_invariants(&ctx);
-    }
-
-    #[test]
-    fn balance_conservation_catches_inflation_on_success() {
-        // Arrange: one account with balance 100.
-        let acc_id = nssa::AccountId::new([1_u8; 32]);
-        let state_before = V03State::new_with_genesis_accounts(&[(acc_id, 100)], vec![], 0);
-        // Simulate execution that inflated the balance to 200.
-        let state_after = V03State::new_with_genesis_accounts(&[(acc_id, 200)], vec![], 0);
-
-        let mut balances = std::collections::HashMap::new();
-        balances.insert(acc_id, 100_u128);
-
-        let ctx = InvariantCtx {
-            state_before: &state_before,
-            state_after: &state_after,
-            execution_succeeded: true,
-            balances_before: BalanceSnapshot(balances),
-            nonces_before: make_empty_nonce_snapshot(),
-        };
-
-        let result = std::panic::catch_unwind(|| assert_invariants(&ctx));
-        assert!(result.is_err(), "expected panic for balance inflation");
-    }
-
-    #[test]
-    fn nonce_increment_correctness_passes_with_no_signers() {
-        // Empty signer list — no accounts to check; trivially satisfies the invariant.
-        let state = make_empty_state();
-        assert_nonce_increment_correctness(&[], &make_empty_nonce_snapshot(), &state);
-    }
-
-    #[test]
-    fn nonce_increment_correctness_passes_when_signer_not_in_snapshot() {
-        // Signer ID is present in the list but absent from the snapshot — skipped.
-        let acc_id = nssa::AccountId::new([9_u8; 32]);
-        let state = make_empty_state();
-        // Empty snapshot → `continue` branch fires; no assertion is made.
-        assert_nonce_increment_correctness(&[acc_id], &make_empty_nonce_snapshot(), &state);
-    }
-
-    #[test]
-    fn nonce_increment_correctness_catches_unchanged_nonce() {
-        // Arrange: signer has nonce 5 in the snapshot; the state returns Nonce(0) for the
-        // same account (genesis default).  expected = Nonce(6), actual = Nonce(0) → VIOLATION.
-        let acc_id = nssa::AccountId::new([3_u8; 32]);
-        let state = V03State::new_with_genesis_accounts(&[], vec![], 0);
-
-        let mut nonces = std::collections::HashMap::new();
-        nonces.insert(acc_id, Nonce(5));
-
-        let result = std::panic::catch_unwind(|| {
-            assert_nonce_increment_correctness(&[acc_id], &NonceSnapshot(nonces), &state);
-        });
-        assert!(result.is_err(), "expected panic for unchanged nonce");
-    }
-
-    #[test]
-    fn failed_tx_nonce_stability_catches_nonce_mutation() {
-        let acc_id = nssa::AccountId::new([2_u8; 32]);
-        // before: nonce 5; after: nonce 6 (should not happen on failure)
-        let state_before = V03State::new_with_genesis_accounts(&[(acc_id, 100)], vec![], 0);
-        let state_after = V03State::new_with_genesis_accounts(&[(acc_id, 100)], vec![], 0);
-
-        // We check the nonce snapshot directly; the states both return default nonce (0).
-        // Fake a discrepancy by inserting nonce=1 in the snapshot while state_after has nonce=0.
-        let mut nonces = std::collections::HashMap::new();
-        // Nonce(1) in snapshot, but state_after will return Nonce(0).
-        nonces.insert(acc_id, Nonce(1));
-
-        let mut balances = std::collections::HashMap::new();
-        balances.insert(acc_id, 100_u128);
-
-        let ctx = InvariantCtx {
-            state_before: &state_before,
-            state_after: &state_after,
-            execution_succeeded: false,
-            balances_before: BalanceSnapshot(balances),
-            nonces_before: NonceSnapshot(nonces),
-        };
-
-        let result = std::panic::catch_unwind(|| assert_invariants(&ctx));
-        assert!(
-            result.is_err(),
-            "expected panic for nonce mutation on failure"
-        );
-    }
-}
-
-// ── ReplayRejection proptest suite ───────────────────────────────────────────
-//
-// This suite constitutes the formal, reproducible exercise of the ReplayRejection
-// invariant.  It generates a realistic initial state and a correctly-signed
-// native-transfer transaction, applies it once, and asserts that a second
-// application is rejected.
-//
-// Run with: cargo test -p fuzz_props replay_rejection
-#[cfg(test)]
-mod replay_proptest {
-    use crate::generators::{arb_native_transfer_tx, test_accounts};
-    use nssa::V03State;
-    use proptest::prelude::*;
-
-    /// Build a `V03State` from the testnet accounts, assigning each a fixed
-    /// balance large enough for any reasonable transfer amount.
-    fn make_test_state() -> V03State {
-        let accounts = test_accounts();
-        let init_accs: Vec<(nssa::AccountId, u128)> = accounts
-            .iter()
-            .map(|(id, _)| (*id, 1_000_000_u128))
-            .collect();
-        V03State::new_with_genesis_accounts(&init_accs, vec![], 0)
-    }
-
-    proptest! {
-        /// **ReplayRejection** \u{2014} a transaction accepted in block N must be
-        /// rejected when replayed in block N+1, because the nonce is consumed
-        /// on first acceptance.
-        #[test]
-        fn replay_rejection_proptest(tx in arb_native_transfer_tx(test_accounts())) {
-            let mut state = make_test_state();
-
-            // Stateless gate \u{2014} skip structurally invalid transactions (e.g. those
-            // whose public key does not match the declared sender).
-            let Ok(validated_tx) = tx.transaction_stateless_check() else { return Ok(()) };
-
-            // First application \u{2014} may fail for state-level reasons (e.g. sender
-            // has insufficient balance, wrong nonce).  In that case there is
-            // nothing to replay.
-            let first_result = validated_tx.execute_check_on_state(&mut state, 1, 0);
-
-            if let Ok(applied_tx) = first_result {
-                // Use the shared framework function.  assert_replay_rejection uses
-                // assert!() rather than prop_assert!(); for structured proptest
-                // inputs the framework-level panic is equivalent.
-                super::assert_replay_rejection(applied_tx, &mut state, 2, 1);
-            }
-        }
-    }
-}
diff --git a/fuzz_props/src/lib.rs b/fuzz_props/src/lib.rs
index ffba17a..6c45ffd 100644
--- a/fuzz_props/src/lib.rs
+++ b/fuzz_props/src/lib.rs
@@ -86,33 +86,4 @@ macro_rules! fuzz_entry {
 }
 
 #[cfg(test)]
-mod seed_gen {
-    use std::fs;
-    use std::path::Path;
-
-    #[test]
-    fn generate_seeds() {
-        let tx = common::test_utils::produce_dummy_empty_transaction();
-        let bytes = borsh::to_vec(&tx).unwrap();
-
-        // CARGO_MANIFEST_DIR is lez-fuzzing/fuzz_props/ at compile time.
-        // Tests inherit the package directory as cwd, so we must use an
-        // absolute base rather than a bare relative path.
-        let workspace_root = Path::new(env!("CARGO_MANIFEST_DIR"))
-            .parent()
-            .expect("fuzz_props is one level below the workspace root");
-
-        let targets = [
-            "fuzz/corpus/fuzz_transaction_decoding/seed_empty_tx",
-            "fuzz/corpus/fuzz_stateless_verification/seed_empty_tx",
-            "fuzz/corpus/fuzz_state_transition/seed_empty_tx",
-        ];
-        for rel in &targets {
-            let p = workspace_root.join(rel);
-            if let Some(parent) = p.parent() {
-                let _ = fs::create_dir_all(parent);
-            }
-            let _ = fs::write(&p, &bytes);
-        }
-    }
-}
+mod tests;
diff --git a/fuzz_props/src/tests.rs b/fuzz_props/src/tests.rs
new file mode 100644
index 0000000..759db83
--- /dev/null
+++ b/fuzz_props/src/tests.rs
@@ -0,0 +1,3 @@
+mod invariants;
+mod replay_proptest;
+mod seed_gen;
diff --git a/fuzz_props/src/tests/invariants.rs b/fuzz_props/src/tests/invariants.rs
new file mode 100644
index 0000000..59c6217
--- /dev/null
+++ b/fuzz_props/src/tests/invariants.rs
@@ -0,0 +1,119 @@
+use crate::invariants::{
+    BalanceSnapshot, InvariantCtx, NonceSnapshot, assert_invariants,
+    assert_nonce_increment_correctness,
+};
+use nssa::V03State;
+use nssa_core::account::Nonce;
+
+fn make_empty_state() -> V03State {
+    V03State::new_with_genesis_accounts(&[], vec![], 0)
+}
+
+fn make_empty_snapshot() -> BalanceSnapshot {
+    BalanceSnapshot(std::collections::HashMap::new())
+}
+
+fn make_empty_nonce_snapshot() -> NonceSnapshot {
+    NonceSnapshot(std::collections::HashMap::new())
+}
+
+#[test]
+fn invariant_state_isolation_on_failure_does_not_panic_on_error() {
+    let state = make_empty_state();
+    let ctx = InvariantCtx {
+        state_before: &state,
+        state_after: &state,
+        execution_succeeded: false,
+        balances_before: make_empty_snapshot(),
+        nonces_before: make_empty_nonce_snapshot(),
+    };
+    assert_invariants(&ctx);
+}
+
+#[test]
+fn invariant_replay_rejection_does_not_panic() {
+    let state = make_empty_state();
+    let ctx = InvariantCtx {
+        state_before: &state,
+        state_after: &state,
+        execution_succeeded: true,
+        balances_before: make_empty_snapshot(),
+        nonces_before: make_empty_nonce_snapshot(),
+    };
+    assert_invariants(&ctx);
+}
+
+#[test]
+fn balance_conservation_catches_inflation_on_success() {
+    let acc_id = nssa::AccountId::new([1_u8; 32]);
+    let state_before = V03State::new_with_genesis_accounts(&[(acc_id, 100)], vec![], 0);
+    let state_after = V03State::new_with_genesis_accounts(&[(acc_id, 200)], vec![], 0);
+
+    let mut balances = std::collections::HashMap::new();
+    balances.insert(acc_id, 100_u128);
+
+    let ctx = InvariantCtx {
+        state_before: &state_before,
+        state_after: &state_after,
+        execution_succeeded: true,
+        balances_before: BalanceSnapshot(balances),
+        nonces_before: make_empty_nonce_snapshot(),
+    };
+
+    let result = std::panic::catch_unwind(|| assert_invariants(&ctx));
+    assert!(result.is_err(), "expected panic for balance inflation");
+}
+
+#[test]
+fn nonce_increment_correctness_passes_with_no_signers() {
+    let state = make_empty_state();
+    assert_nonce_increment_correctness(&[], &make_empty_nonce_snapshot(), &state);
+}
+
+#[test]
+fn nonce_increment_correctness_passes_when_signer_not_in_snapshot() {
+    let acc_id = nssa::AccountId::new([9_u8; 32]);
+    let state = make_empty_state();
+    assert_nonce_increment_correctness(&[acc_id], &make_empty_nonce_snapshot(), &state);
+}
+
+#[test]
+fn nonce_increment_correctness_catches_unchanged_nonce() {
+    let acc_id = nssa::AccountId::new([3_u8; 32]);
+    let state = V03State::new_with_genesis_accounts(&[], vec![], 0);
+
+    let mut nonces = std::collections::HashMap::new();
+    nonces.insert(acc_id, Nonce(5));
+
+    let result = std::panic::catch_unwind(|| {
+        assert_nonce_increment_correctness(&[acc_id], &NonceSnapshot(nonces), &state);
+    });
+    assert!(result.is_err(), "expected panic for unchanged nonce");
+}
+
+#[test]
+fn failed_tx_nonce_stability_catches_nonce_mutation() {
+    let acc_id = nssa::AccountId::new([2_u8; 32]);
+    let state_before = V03State::new_with_genesis_accounts(&[(acc_id, 100)], vec![], 0);
+    let state_after = V03State::new_with_genesis_accounts(&[(acc_id, 100)], vec![], 0);
+
+    let mut nonces = std::collections::HashMap::new();
+    nonces.insert(acc_id, Nonce(1));
+
+    let mut balances = std::collections::HashMap::new();
+    balances.insert(acc_id, 100_u128);
+
+    let ctx = InvariantCtx {
+        state_before: &state_before,
+        state_after: &state_after,
+        execution_succeeded: false,
+        balances_before: BalanceSnapshot(balances),
+        nonces_before: NonceSnapshot(nonces),
+    };
+
+    let result = std::panic::catch_unwind(|| assert_invariants(&ctx));
+    assert!(
+        result.is_err(),
+        "expected panic for nonce mutation on failure"
+    );
+}
diff --git a/fuzz_props/src/tests/replay_proptest.rs b/fuzz_props/src/tests/replay_proptest.rs
new file mode 100644
index 0000000..6be98a8
--- /dev/null
+++ b/fuzz_props/src/tests/replay_proptest.rs
@@ -0,0 +1,33 @@
+// Run with: cargo test -p fuzz_props replay_rejection
+use crate::generators::{arb_native_transfer_tx, test_accounts};
+use nssa::V03State;
+use proptest::prelude::*;
+
+fn make_test_state() -> V03State {
+    let accounts = test_accounts();
+    let init_accs: Vec<(nssa::AccountId, u128)> = accounts
+        .iter()
+        .map(|(id, _)| (*id, 1_000_000_u128))
+        .collect();
+    V03State::new_with_genesis_accounts(&init_accs, vec![], 0)
+}
+
+proptest! {
+    /// **ReplayRejection** \u{2014} a transaction accepted in block N must be
+    /// rejected when replayed in block N+1, because the nonce is consumed
+    /// on first acceptance.
+    #[test]
+    fn replay_rejection_proptest(tx in arb_native_transfer_tx(test_accounts())) {
+        let mut state = make_test_state();
+
+        // Skip structurally invalid transactions (e.g. mismatched public key / sender).
+        let Ok(validated_tx) = tx.transaction_stateless_check() else { return Ok(()) };
+
+        // First application may fail for state-level reasons; nothing to replay then.
+        let first_result = validated_tx.execute_check_on_state(&mut state, 1, 0);
+
+        if let Ok(applied_tx) = first_result {
+            crate::invariants::assert_replay_rejection(applied_tx, &mut state, 2, 1);
+        }
+    }
+}
diff --git a/fuzz_props/src/tests/seed_gen.rs b/fuzz_props/src/tests/seed_gen.rs
new file mode 100644
index 0000000..7548307
--- /dev/null
+++ b/fuzz_props/src/tests/seed_gen.rs
@@ -0,0 +1,25 @@
+use std::fs;
+use std::path::Path;
+
+#[test]
+fn generate_seeds() {
+    let tx = common::test_utils::produce_dummy_empty_transaction();
+    let bytes = borsh::to_vec(&tx).unwrap();
+
+    let workspace_root = Path::new(env!("CARGO_MANIFEST_DIR"))
+        .parent()
+        .expect("fuzz_props is one level below the workspace root");
+
+    let targets = [
+        "fuzz/corpus/fuzz_transaction_decoding/seed_empty_tx",
+        "fuzz/corpus/fuzz_stateless_verification/seed_empty_tx",
+        "fuzz/corpus/fuzz_state_transition/seed_empty_tx",
+    ];
+    for rel in &targets {
+        let p = workspace_root.join(rel);
+        if let Some(parent) = p.parent() {
+            let _ = fs::create_dir_all(parent);
+        }
+        let _ = fs::write(&p, &bytes);
+    }
+}