diff --git a/unitary/alpha/quantum_effect_test.py b/unitary/alpha/quantum_effect_test.py
index 2f1cd352..2b2623ca 100644
--- a/unitary/alpha/quantum_effect_test.py
+++ b/unitary/alpha/quantum_effect_test.py
@@ -17,14 +17,13 @@
 import cirq
 
 import unitary.alpha as alpha
-from unitary.alpha.sparse_vector_simulator import SparseSimulator
 
 Q0 = cirq.NamedQubit("q0")
 Q1 = cirq.NamedQubit("q1")
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_quantum_if(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece = alpha.QuantumObject("q0", 1)
@@ -46,7 +45,7 @@ def test_quantum_if(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_anti_control(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece = alpha.QuantumObject("q0", 0)
diff --git a/unitary/alpha/quantum_object_test.py b/unitary/alpha/quantum_object_test.py
index c29ed4c8..70b76b25 100644
--- a/unitary/alpha/quantum_object_test.py
+++ b/unitary/alpha/quantum_object_test.py
@@ -18,11 +18,10 @@
 import cirq
 
 import unitary.alpha as alpha
-from unitary.alpha.sparse_vector_simulator import SparseSimulator
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_negation(simulator, compile_to_qubits):
     piece = alpha.QuantumObject("t", 0)
     board = alpha.QuantumWorld(
@@ -38,7 +37,7 @@ def test_negation(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_add_world_after_state_change(simulator, compile_to_qubits):
     piece = alpha.QuantumObject("t", 0)
     piece += 1
diff --git a/unitary/alpha/qubit_effects_test.py b/unitary/alpha/qubit_effects_test.py
index 6da69ecb..4d35e6ca 100644
--- a/unitary/alpha/qubit_effects_test.py
+++ b/unitary/alpha/qubit_effects_test.py
@@ -18,11 +18,10 @@
 import cirq
 
 import unitary.alpha as alpha
-from unitary.alpha.sparse_vector_simulator import SparseSimulator
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_flip(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece = alpha.QuantumObject("t", 0)
@@ -33,7 +32,7 @@ def test_flip(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_partial_flip(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece = alpha.QuantumObject("t", 0)
@@ -44,7 +43,7 @@ def test_partial_flip(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_partial_flip_multiple(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece = alpha.QuantumObject("t", 0)
@@ -56,7 +55,7 @@ def test_partial_flip_multiple(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_phase(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece = alpha.QuantumObject("t", 0)
@@ -67,7 +66,7 @@ def test_phase(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_partial_phase(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece = alpha.QuantumObject("t", 0)
@@ -78,7 +77,7 @@ def test_partial_phase(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_superposition(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece = alpha.QuantumObject("t", 0)
@@ -89,7 +88,7 @@ def test_superposition(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_move(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece1 = alpha.QuantumObject("a", 1)
@@ -110,7 +109,7 @@ def test_move(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_partial_move(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece1 = alpha.QuantumObject("a", 1)
@@ -133,7 +132,7 @@ def test_partial_move(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_phased_move(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece1 = alpha.QuantumObject("a", 1)
@@ -154,7 +153,7 @@ def test_phased_move(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_partial_phased_move(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece1 = alpha.QuantumObject("a", 1)
@@ -177,7 +176,7 @@ def test_partial_phased_move(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_split(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece1 = alpha.QuantumObject("a", 1)
@@ -199,7 +198,7 @@ def test_split(simulator, compile_to_qubits):
 
 
 @pytest.mark.parametrize("compile_to_qubits", [False, True])
-@pytest.mark.parametrize("simulator", [cirq.Simulator, SparseSimulator])
+@pytest.mark.parametrize("simulator", [cirq.Simulator, alpha.SparseSimulator])
 def test_phased_split(simulator, compile_to_qubits):
     board = alpha.QuantumWorld(sampler=simulator(), compile_to_qubits=compile_to_qubits)
     piece1 = alpha.QuantumObject("a", 1)