diff --git a/notebooks/pMHN-Development-JAX.py b/notebooks/pMHN-Development-JAX.py
index f755617..11668d1 100644
--- a/notebooks/pMHN-Development-JAX.py
+++ b/notebooks/pMHN-Development-JAX.py
@@ -159,7 +159,6 @@ def generate_loglikelihood(
     theta_link_fn=None,
     omega_link_fn=None,
 ):
-
     if theta_link_fn is None:
         theta_link_fn = _default_theta_link(dataset.n_genes)
     if omega_link_fn is None:
diff --git a/src/pmhn/_simulate/__init__.py b/src/pmhn/_simulate/__init__.py
index 249c743..2d224d3 100644
--- a/src/pmhn/_simulate/__init__.py
+++ b/src/pmhn/_simulate/__init__.py
@@ -1,4 +1,5 @@
 """The simulation utilities."""
+
 from pmhn._simulate._jump_chain import (
     simulate_dataset,
     simulate_genotype_known_time,
diff --git a/src/pmhn/_simulate/_jump_chain.py b/src/pmhn/_simulate/_jump_chain.py
index d6a04fc..92ff7df 100644
--- a/src/pmhn/_simulate/_jump_chain.py
+++ b/src/pmhn/_simulate/_jump_chain.py
@@ -1,4 +1,5 @@
 """The jump Markov chain simulation from an underlying Markov process."""
+
 from typing import Optional, Union, Sequence
 
 import numpy as np
diff --git a/src/pmhn/_trees/_backend_jax/_private_api.py b/src/pmhn/_trees/_backend_jax/_private_api.py
index 18c7735..3b2a963 100644
--- a/src/pmhn/_trees/_backend_jax/_private_api.py
+++ b/src/pmhn/_trees/_backend_jax/_private_api.py
@@ -1,4 +1,5 @@
 """This is *private* API, which is convenient for testing and experimenting."""
+
 import pmhn._trees._backend_jax._rates as rates
 from pmhn._trees._backend_jax._loglikelihood import loglikelihood
 from pmhn._trees._backend_jax._solver import logprob_forward_substitution
diff --git a/src/pmhn/_trees/_backend_jax/_rates.py b/src/pmhn/_trees/_backend_jax/_rates.py
index d09f2ae..26df03f 100644
--- a/src/pmhn/_trees/_backend_jax/_rates.py
+++ b/src/pmhn/_trees/_backend_jax/_rates.py
@@ -1,4 +1,5 @@
 """Submodule used to construct the rates matrices from wrapped tree."""
+
 import jax
 import jax.numpy as jnp
 from jaxtyping import Array, Float, Int
diff --git a/src/pmhn/_trees/_interfaces.py b/src/pmhn/_trees/_interfaces.py
index 016fdca..295a117 100644
--- a/src/pmhn/_trees/_interfaces.py
+++ b/src/pmhn/_trees/_interfaces.py
@@ -1,4 +1,5 @@
 """Interfaces."""
+
 from typing import TypeAlias
 from anytree import Node
 
diff --git a/src/pmhn/_trees/_io.py b/src/pmhn/_trees/_io.py
index 51602e7..0ab7cc9 100644
--- a/src/pmhn/_trees/_io.py
+++ b/src/pmhn/_trees/_io.py
@@ -1,4 +1,5 @@
 """Utilities for parsing data frames into AnyTree trees."""
+
 import dataclasses
 from typing import Any
 
diff --git a/src/pmhn/_trees/_validate.py b/src/pmhn/_trees/_validate.py
index cb45f27..ba5f512 100644
--- a/src/pmhn/_trees/_validate.py
+++ b/src/pmhn/_trees/_validate.py
@@ -1,4 +1,5 @@
 """Tree validation utilities."""
+
 from pmhn._trees._interfaces import Tree