diff --git a/hive/agents/rainbow.py b/hive/agents/rainbow.py
index 2e795090..a6339dc0 100644
--- a/hive/agents/rainbow.py
+++ b/hive/agents/rainbow.py
@@ -221,7 +221,6 @@ def create_q_networks(self, representation_net):
 
     @torch.no_grad()
     def act(self, observation, agent_traj_state=None):
-
         if self._training:
             if not self._learn_schedule.get_value():
                 epsilon = 1.0
diff --git a/hive/agents/td3.py b/hive/agents/td3.py
index dad56ae4..4fecd247 100644
--- a/hive/agents/td3.py
+++ b/hive/agents/td3.py
@@ -399,7 +399,7 @@ def update(self, update_info, agent_traj_state=None):
 
     def _update_target(self):
         """Update the target network."""
-        for (network, target_network) in [
+        for network, target_network in [
             (self._actor, self._target_actor),
             (self._critic, self._target_critic),
         ]:
diff --git a/hive/envs/marlgrid/ma_envs/base.py b/hive/envs/marlgrid/ma_envs/base.py
index 554297c3..2f1833bd 100644
--- a/hive/envs/marlgrid/ma_envs/base.py
+++ b/hive/envs/marlgrid/ma_envs/base.py
@@ -135,7 +135,6 @@ def render(
         )
 
         if show_agent_views:
-
             target_partial_width = int(
                 img.shape[0] * agent_col_width_frac - 2 * agent_col_padding_px
             )
diff --git a/hive/envs/marlgrid/ma_envs/checkers.py b/hive/envs/marlgrid/ma_envs/checkers.py
index f7eb44e3..62065565 100644
--- a/hive/envs/marlgrid/ma_envs/checkers.py
+++ b/hive/envs/marlgrid/ma_envs/checkers.py
@@ -85,7 +85,6 @@ def step(self, actions):
             agent.step_reward = 0
 
             if agent.active:
-
                 cur_pos = agent.pos[:]
                 cur_cell = self.grid.get(*cur_pos)
                 fwd_pos = agent.front_pos[:]
diff --git a/hive/envs/marlgrid/ma_envs/pursuit.py b/hive/envs/marlgrid/ma_envs/pursuit.py
index 6d964b26..8137b994 100644
--- a/hive/envs/marlgrid/ma_envs/pursuit.py
+++ b/hive/envs/marlgrid/ma_envs/pursuit.py
@@ -54,7 +54,6 @@ def step(self, actions):
             agent.step_reward = 0
 
             if agent.active:
-
                 cur_pos = agent.pos[:]
                 cur_cell = self.grid.get(*cur_pos)
                 fwd_pos = agent.front_pos[:]
diff --git a/hive/replays/circular_replay.py b/hive/replays/circular_replay.py
index 4c2a7e01..26bd38fb 100644
--- a/hive/replays/circular_replay.py
+++ b/hive/replays/circular_replay.py
@@ -334,7 +334,6 @@ class SimpleReplayBuffer(BaseReplayBuffer):
     """
 
     def __init__(self, capacity=1e5, compress=False, seed=42, **kwargs):
-
         self._numpy_rng = np.random.default_rng(seed)
         self._capacity = int(capacity)
         self._compress = compress
diff --git a/tests/hive/replays/test_recurrent_buffer.py b/tests/hive/replays/test_recurrent_buffer.py
new file mode 100644
index 00000000..739c667b
--- /dev/null
+++ b/tests/hive/replays/test_recurrent_buffer.py
@@ -0,0 +1,208 @@
+import numpy as np
+import pytest
+from pytest_lazyfixture import lazy_fixture
+
+from hive.replays.recurrent_replay import RecurrentReplayBuffer
+
+
+OBS_SHAPE = (2, 2)
+CAPACITY = 60
+MAX_SEQ_LEN = 10
+N_STEP_HORIZON = 2
+GAMMA = 1
+
+
+@pytest.fixture()
+def rec_buffer():
+    return RecurrentReplayBuffer(
+        capacity=CAPACITY,
+        max_seq_len=MAX_SEQ_LEN,
+        observation_shape=OBS_SHAPE,
+        observation_dtype=np.float32,
+        extra_storage_types={"priority": (np.int8, ())},
+    )
+
+
+@pytest.fixture(
+    params=[
+        pytest.lazy_fixture("rec_buffer"),
+    ]
+)
+def buffer(request):
+    return request.param
+
+
+### truncated and terminated instead of done???
+@pytest.fixture()
+def full_buffer(buffer):
+    done_time = 15
+    for i in range(33):  # until the buffer is full instead of CAPACITY
+        buffer.add(
+            observation=np.ones(OBS_SHAPE) * i,
+            action=(i % done_time) + 1,
+            reward=(i % done_time) + 1,
+            done=((i + 1) % done_time) == 0,
+            priority=(i % 10) + 1,
+        )
+    return buffer
+
+
+@pytest.fixture()
+def full_n_step_buffer():
+    n_step_buffer = RecurrentReplayBuffer(
+        capacity=CAPACITY,
+        max_seq_len=MAX_SEQ_LEN,
+        observation_shape=OBS_SHAPE,
+        observation_dtype=np.float32,
+        n_step=N_STEP_HORIZON,
+        gamma=GAMMA,
+    )
+    done_time = 15
+    for i in range(33):  # until the buffer is full instead of CAPACITY
+        n_step_buffer.add(
+            observation=np.ones(OBS_SHAPE) * i,
+            action=(i % done_time) + 1,
+            reward=(i % done_time) + 1,
+            done=((i + 1) % done_time) == 0,
+            priority=(i % 10) + 1,
+        )
+    return n_step_buffer
+
+
+@pytest.mark.parametrize("constructor", [RecurrentReplayBuffer])
+@pytest.mark.parametrize("observation_shape", [(), (2,), (3, 4)])
+@pytest.mark.parametrize("observation_dtype", [np.uint8, np.float32])
+@pytest.mark.parametrize("action_shape", [(), (5,)])
+@pytest.mark.parametrize("action_dtype", [np.int8, np.float32])
+@pytest.mark.parametrize("reward_shape", [(), (6,)])
+@pytest.mark.parametrize("reward_dtype", [np.int8, np.float32])
+@pytest.mark.parametrize("extra_storage_types", [None, {"foo": (np.float32, (7,))}])
+def test_constructor(
+    constructor,
+    observation_shape,
+    observation_dtype,
+    action_shape,
+    action_dtype,
+    reward_shape,
+    reward_dtype,
+    extra_storage_types,
+):
+    buffer = constructor(
+        capacity=10,
+        max_seq_len=MAX_SEQ_LEN,
+        observation_shape=observation_shape,
+        observation_dtype=observation_dtype,
+        action_shape=action_shape,
+        action_dtype=action_dtype,
+        reward_shape=reward_shape,
+        reward_dtype=reward_dtype,
+        extra_storage_types=extra_storage_types,
+    )
+    assert buffer.size() == 0
+    assert buffer._max_seq_len == MAX_SEQ_LEN
+    assert buffer._storage["observation"].shape == (10,) + observation_shape
+    assert buffer._storage["observation"].dtype == observation_dtype
+    assert buffer._storage["action"].shape == (10,) + action_shape
+    assert buffer._storage["action"].dtype == action_dtype
+    assert buffer._storage["reward"].shape == (10,) + reward_shape
+    assert buffer._storage["reward"].dtype == reward_dtype
+    if extra_storage_types is not None:
+        for key in extra_storage_types:
+            assert buffer._storage[key].shape == (10,) + extra_storage_types[key][1]
+            assert buffer._storage[key].dtype == extra_storage_types[key][0]
+
+
+def test_add(buffer):
+    assert buffer.size() == 0
+    ## add to the buffer until the buffer is full
+    done_time = 15
+    for i in range(33):  # until the buffer is full instead of CAPACITY
+        buffer.add(
+            observation=np.ones(OBS_SHAPE) * i,
+            action=i,
+            reward=i % 10,
+            done=((i + 1) % done_time) == 0,
+            priority=(i % 10) + 1,
+        )
+
+        assert buffer.size() == i + ((i) // done_time) * (MAX_SEQ_LEN - 1)
+        assert (
+            buffer._cursor
+            == ((i + MAX_SEQ_LEN) + (((i) // done_time) * (MAX_SEQ_LEN - 1))) % CAPACITY
+        )
+
+    ## when the buffer is full
+    more_steps = 40
+    for i in range(more_steps):
+        buffer.add(
+            observation=np.ones(OBS_SHAPE) * i,
+            action=i,
+            reward=i % 10,
+            done=((i + 1) % done_time) == 0,
+            priority=(i % 10) + 1,
+        )
+        assert buffer.size() == CAPACITY - MAX_SEQ_LEN
+        assert buffer._cursor == (
+            ((i + 1) + (((i) // done_time) * (MAX_SEQ_LEN - 1))) % CAPACITY
+        )
+
+    assert (
+        buffer._num_added
+        == (more_steps + (((i) // done_time) * (MAX_SEQ_LEN - 1))) + CAPACITY
+    )
+
+
+def test_sample_shape(full_buffer):
+    # sample transitions from buffer
+    batch_size = CAPACITY - 1
+    batch = full_buffer.sample(batch_size)
+    # check if the shape of batch is correct
+    assert batch["indices"].shape == (batch_size,)
+    assert batch["observation"].shape == (batch_size, 10) + OBS_SHAPE
+    assert batch["action"].shape == (batch_size, 10)
+    assert batch["done"].shape == (batch_size, 10)
+    assert batch["reward"].shape == (batch_size, 10)
+    assert batch["trajectory_lengths"].shape == (batch_size,)
+    assert batch["next_observation"].shape == (batch_size, 10) + OBS_SHAPE
+
+
+def test_sample(full_buffer):
+    # sample transitions from buffer
+    batch_size = 50
+    batch = full_buffer.sample(batch_size)
+    for b in range(batch_size):
+        t = 0
+
+        while batch["action"][b, t] == 0:
+            t += 1
+
+        while t < MAX_SEQ_LEN and batch["action"][b, t] > 0:
+            if t > 0:
+                assert batch["action"][b, t] - batch["action"][b, t - 1] == 1
+                assert batch["reward"][b, t] - batch["reward"][b, t - 1] == 1
+            t += 1
+
+
+def test_sample_n_step(full_n_step_buffer):
+    # sample transitions from buffer
+    batch_size = 50
+    batch = full_n_step_buffer.sample(batch_size)
+    for b in range(batch_size):
+        t = 0
+
+        while batch["action"][b, t] == 0:
+            t += 1
+
+        while t < MAX_SEQ_LEN - 1 and batch["action"][b, t] > 0:
+            if t > 0:
+                assert batch["action"][b, t] - batch["action"][b, t - 1] == 1
+                if t == full_n_step_buffer.size() - 1 or batch["reward"][b, t + 1] == 0:
+                    assert (
+                        batch["reward"][b, t] - batch["reward"][b, t - 1]
+                        == 1 - batch["reward"][b, t] * GAMMA
+                    )
+                else:
+                    assert (
+                        batch["reward"][b, t] - batch["reward"][b, t - 1] == 1 + GAMMA
+                    )
+            t += 1