diff --git a/.github/workflows/core_tests.yml b/.github/workflows/core_tests.yml
index 3e8e62176..7a06c3947 100644
--- a/.github/workflows/core_tests.yml
+++ b/.github/workflows/core_tests.yml
@@ -2,9 +2,9 @@ name: Core Tests.
 
 on:
   push:
-    branches: [master]
+    branches: [main]
   pull_request:
-    branches: [master]
+    branches: [main]
 
 permissions:
   contents: read
diff --git a/diff_rast/_torch_impl.py b/diff_rast/_torch_impl.py
index 009d24d51..95c2bb8d0 100644
--- a/diff_rast/_torch_impl.py
+++ b/diff_rast/_torch_impl.py
@@ -6,7 +6,9 @@
 from torch import Tensor
 
 
-def compute_sh_color(viewdirs: Float[Tensor, "*batch 3"], sh_coeffs: Float[Tensor, "*batch D C"]):
+def compute_sh_color(
+    viewdirs: Float[Tensor, "*batch 3"], sh_coeffs: Float[Tensor, "*batch D C"]
+):
     """
     :param viewdirs (*, C)
     :param sh_coeffs (*, D, C) sh coefficients for each color channel
@@ -66,7 +68,9 @@ def eval_sh_bases(basis_dim: int, dirs: torch.Tensor):
 
     :return: torch.Tensor (..., basis_dim)
     """
-    result = torch.empty((*dirs.shape[:-1], basis_dim), dtype=dirs.dtype, device=dirs.device)
+    result = torch.empty(
+        (*dirs.shape[:-1], basis_dim), dtype=dirs.dtype, device=dirs.device
+    )
     result[..., 0] = SH_C0
     if basis_dim > 1:
         x, y, z = dirs.unbind(-1)
@@ -100,7 +104,9 @@ def eval_sh_bases(basis_dim: int, dirs: torch.Tensor):
                     result[..., 21] = SH_C4[5] * xz * (7 * zz - 3)
                     result[..., 22] = SH_C4[6] * (xx - yy) * (7 * zz - 1)
                     result[..., 23] = SH_C4[7] * xz * (xx - 3 * yy)
-                    result[..., 24] = SH_C4[8] * (xx * (xx - 3 * yy) - yy * (3 * xx - yy))
+                    result[..., 24] = SH_C4[8] * (
+                        xx * (xx - 3 * yy) - yy * (3 * xx - yy)
+                    )
     return result
 
 
@@ -148,7 +154,9 @@ def scale_rot_to_cov3d(scale: Tensor, glob_scale: float, quat: Tensor) -> Tensor
     return M @ M.transpose(-1, -2)  # (..., 3, 3)
 
 
-def project_cov3d_ewa(mean3d: Tensor, cov3d: Tensor, viewmat: Tensor, fx: float, fy: float) -> Tensor:
+def project_cov3d_ewa(
+    mean3d: Tensor, cov3d: Tensor, viewmat: Tensor, fx: float, fy: float
+) -> Tensor:
     assert mean3d.shape[-1] == 3, mean3d.shape
     assert cov3d.shape[-2:] == (3, 3), cov3d.shape
     assert viewmat.shape[-2:] == (4, 4), viewmat.shape
@@ -212,7 +220,9 @@ def clip_near_plane(p, viewmat, thresh=0.1):
 
 
 def get_tile_bbox(pix_center, pix_radius, tile_bounds, BLOCK_X=16, BLOCK_Y=16):
-    tile_size = torch.tensor([BLOCK_X, BLOCK_Y], dtype=torch.float32, device=pix_center.device)
+    tile_size = torch.tensor(
+        [BLOCK_X, BLOCK_Y], dtype=torch.float32, device=pix_center.device
+    )
     tile_center = pix_center / tile_size
     tile_radius = pix_radius[..., None] / tile_size
 
@@ -253,7 +263,9 @@ def project_gaussians_forward(
     conic, radius, det_valid = compute_cov2d_bounds(cov2d)
     center = project_pix(projmat, means3d, img_size)
     tile_min, tile_max = get_tile_bbox(center, radius, tile_bounds)
-    tile_area = (tile_max[..., 0] - tile_min[..., 0]) * (tile_max[..., 1] - tile_min[..., 1])
+    tile_area = (tile_max[..., 0] - tile_min[..., 0]) * (
+        tile_max[..., 1] - tile_min[..., 1]
+    )
     mask = (tile_area > 0) & (~is_close) & det_valid
 
     num_tiles_hit = tile_area
diff --git a/diff_rast/cov2d_bounds.py b/diff_rast/cov2d_bounds.py
index ebb32c0cf..0a946c612 100644
--- a/diff_rast/cov2d_bounds.py
+++ b/diff_rast/cov2d_bounds.py
@@ -29,7 +29,9 @@ def forward(
         ), f"Expected input cov2d to be of shape (*batch, 3) (upper triangular values), but got {tuple(cov2d.shape)}"
         num_pts = cov2d.shape[0]
         assert num_pts > 0
-        conic, radius = _C.compute_cov2d_bounds_forward(num_pts, cov2d.contiguous().cuda())
+        conic, radius = _C.compute_cov2d_bounds_forward(
+            num_pts, cov2d.contiguous().cuda()
+        )
         return (conic, radius)
 
     @staticmethod
diff --git a/diff_rast/project_gaussians.py b/diff_rast/project_gaussians.py
index 13ad4990e..ad9e53a54 100644
--- a/diff_rast/project_gaussians.py
+++ b/diff_rast/project_gaussians.py
@@ -40,7 +40,7 @@ def forward(
         img_height: int,
         img_width: int,
         tile_bounds: Tuple[int, int, int],
-        clip_thresh:float=0.01
+        clip_thresh: float = 0.01,
     ):
         num_points = means3d.shape[-2]
 
@@ -102,13 +102,7 @@ def backward(ctx, v_xys, v_depths, v_radii, v_conics, v_num_tiles_hit, v_cov3d):
             conics,
         ) = ctx.saved_tensors
 
-        (
-            v_cov2d,
-            v_cov3d,
-            v_mean3d,
-            v_scale,
-            v_quat,
-        ) = _C.project_gaussians_backward(
+        (v_cov2d, v_cov3d, v_mean3d, v_scale, v_quat,) = _C.project_gaussians_backward(
             ctx.num_points,
             means3d,
             scales,
diff --git a/tests/test_cov2d_bounds.py b/tests/test_cov2d_bounds.py
index f1613dd40..aae9848bd 100644
--- a/tests/test_cov2d_bounds.py
+++ b/tests/test_cov2d_bounds.py
@@ -14,9 +14,16 @@ def compare_binding_to_pytorch():
 
     num_cov2ds = 2
 
-    _covs2d = torch.rand((num_cov2ds, 2, 2), dtype=torch.float32, device=device, requires_grad=True)
+    _covs2d = torch.rand(
+        (num_cov2ds, 2, 2), dtype=torch.float32, device=device, requires_grad=True
+    )
     covs2d = torch.stack(
-        [torch.triu(_covs2d)[:, 0, 0], torch.triu(_covs2d)[:, 0, 1], torch.triu(_covs2d)[:, 1, 1]], dim=-1
+        [
+            torch.triu(_covs2d)[:, 0, 0],
+            torch.triu(_covs2d)[:, 0, 1],
+            torch.triu(_covs2d)[:, 1, 1],
+        ],
+        dim=-1,
     )
 
     conic, radii = compute_cov2d_bounds.apply(covs2d)