diff --git a/cmake/ExternalDependencies.cmake b/cmake/ExternalDependencies.cmake
index 468242ee..399e8d41 100644
--- a/cmake/ExternalDependencies.cmake
+++ b/cmake/ExternalDependencies.cmake
@@ -22,7 +22,7 @@ endif()
 # cmake-format: off
 set(MQT_CORE_VERSION 2.6.1
     CACHE STRING "MQT Core version")
-set(MQT_CORE_REV "89f18fb322ff2ce86e33558e3a2b42a08e655174"
+set(MQT_CORE_REV "41eea72cdbefbd86ba06f76dc41a911950dd3081"
     CACHE STRING "MQT Core identifier (tag, branch or commit hash)")
 set(MQT_CORE_REPO_OWNER "cda-tum"
 	CACHE STRING "MQT Core repository owner (change when using a fork)")
diff --git a/src/mqt/qcec/parameterized.py b/src/mqt/qcec/parameterized.py
index cd94b8e6..211c2927 100644
--- a/src/mqt/qcec/parameterized.py
+++ b/src/mqt/qcec/parameterized.py
@@ -52,7 +52,7 @@ def extract_params(
     p = p1.union(p2)
 
     n_params = len(p)
-    exprs = list(chain(*[instr[0].params for instr in circ1.data + circ2.data if instr[0].params != []]))
+    exprs = list(chain(*[instr.operation.params for instr in circ1.data + circ2.data if instr.operation.params != []]))
 
     def is_expr(x: float | Parameter | ParameterExpression) -> bool:
         return isinstance(x, (Parameter, ParameterExpression))
@@ -115,14 +115,14 @@ def check_parameterized(
     total_simulations_started = 0
     total_simulations_finished = 0
 
-    def update_stats(res: EquivalenceCheckingManager.Results) -> None:
+    def _update_stats(res: EquivalenceCheckingManager.Results) -> None:
         nonlocal total_preprocessing_time, total_runtime, total_simulations_started, total_simulations_finished
         total_preprocessing_time += res.preprocessing_time
         total_runtime += res.check_time
         total_simulations_started += res.started_simulations
         total_simulations_finished += res.performed_simulations
 
-    def write_stats(i: int, res: EquivalenceCheckingManager.Results) -> None:
+    def _write_stats(i: int, res: EquivalenceCheckingManager.Results) -> None:
         nonlocal total_preprocessing_time, total_runtime, total_simulations_started, total_simulations_finished
         res.check_time = total_runtime
         res.preprocessing_time = total_preprocessing_time
@@ -135,7 +135,7 @@ def write_stats(i: int, res: EquivalenceCheckingManager.Results) -> None:
     if res.considered_equivalent():
         return res
 
-    update_stats(res)
+    _update_stats(res)
 
     timeout = __adjust_timeout(configuration.execution.timeout, res)
     n_checks = configuration.parameterized.additional_instantiations
@@ -143,7 +143,7 @@ def write_stats(i: int, res: EquivalenceCheckingManager.Results) -> None:
 
     parameters, mat, offsets = extract_params(circ1, circ2)
 
-    def instantiate_params(
+    def _instantiate_params(
         qc1: QuantumCircuit, qc2: QuantumCircuit, b: NDArray[np.float64]
     ) -> tuple[QuantumCircuit, QuantumCircuit, float]:
         start_time = time.time()
@@ -153,60 +153,61 @@ def instantiate_params(
         qc1_bound = qc1.assign_parameters(param_map)
         qc2_bound = qc2.assign_parameters(param_map)
 
-        def round_zero_params(qc: QuantumCircuit) -> QuantumCircuit:
+        def _round_zero_params(qc: QuantumCircuit) -> QuantumCircuit:
             for instr in qc.data:
-                if not hasattr(instr[0], "mutable") or instr[0].mutable:
-                    params = instr[0].params
-                    instr[0].params = [float(x) for x in params]
-                    instr[0].params = [0 if np.abs(x) < tol else x for x in instr[0].params]
+                operation = instr.operation
+                if not hasattr(operation, "mutable") or operation.mutable:
+                    params = operation.params
+                    operation.params = [float(x) for x in params]
+                    operation.params = [0 if np.abs(x) < tol else x for x in operation.params]
             return qc
 
-        qc1_bound = round_zero_params(qc1_bound)
-        qc2_bound = round_zero_params(qc2_bound)
+        qc1_bound = _round_zero_params(qc1_bound)
+        qc2_bound = _round_zero_params(qc2_bound)
         return qc1_bound, qc2_bound, time.time() - start_time
 
-    def instantiate_params_zero(
+    def _instantiate_params_zero(
         qc1: QuantumCircuit, qc2: QuantumCircuit
     ) -> tuple[QuantumCircuit, QuantumCircuit, float]:
-        return instantiate_params(qc1, qc2, offsets)
+        return _instantiate_params(qc1, qc2, offsets)
 
-    def instantiate_params_phases(
+    def _instantiate_params_phases(
         qc1: QuantumCircuit, qc2: QuantumCircuit
     ) -> tuple[QuantumCircuit, QuantumCircuit, float]:
         phases = [0, np.pi, np.pi / 2, -np.pi / 2, np.pi / 4, -np.pi / 4]
         rng = np.random.default_rng()
         b = rng.choice(phases, size=len(offsets)) + offsets
-        return instantiate_params(qc1, qc2, b)
+        return _instantiate_params(qc1, qc2, b)
 
-    circ1_inst, circ2_inst, runtime = instantiate_params_zero(circ1, circ2)
+    circ1_inst, circ2_inst, runtime = _instantiate_params_zero(circ1, circ2)
     timeout = __adjust_timeout(timeout, runtime)
 
     if timeout < 0:
-        write_stats(1, res)
+        _write_stats(1, res)
         res.equivalence = EquivalenceCriterion.no_information
         return res
 
     res = check_instantiated(circ1_inst, circ2_inst, configuration)
-    update_stats(res)
+    _update_stats(res)
     if res.equivalence == EquivalenceCriterion.not_equivalent:
-        write_stats(1, res)
+        _write_stats(1, res)
         return res
 
     for i in range(n_checks):
-        circ1_inst, circ2_inst, runtime = instantiate_params_phases(circ1, circ2)
+        circ1_inst, circ2_inst, runtime = _instantiate_params_phases(circ1, circ2)
         timeout = __adjust_timeout(timeout, runtime)
         res = check_instantiated(circ1_inst, circ2_inst, configuration)
         timeout = __adjust_timeout(timeout, res)
 
         if timeout < 0:
-            write_stats(i + 2, res)
+            _write_stats(i + 2, res)
             res.equivalence = EquivalenceCriterion.no_information
             return res
 
-        update_stats(res)
+        _update_stats(res)
 
         if res.equivalence == EquivalenceCriterion.not_equivalent:
-            write_stats(i + 2, res)
+            _write_stats(i + 2, res)
             return res
 
     res = check_instantiated_random(circ1, circ2, parameters, configuration)
@@ -214,6 +215,6 @@ def instantiate_params_phases(
     if timeout < 0:
         res.equivalence = EquivalenceCriterion.no_information
 
-    update_stats(res)
-    write_stats(n_checks + 2, res)
+    _update_stats(res)
+    _write_stats(n_checks + 2, res)
     return res