diff --git a/src/readyplayerme/meshops/mesh.py b/src/readyplayerme/meshops/mesh.py
index 1fd6465..787ca28 100644
--- a/src/readyplayerme/meshops/mesh.py
+++ b/src/readyplayerme/meshops/mesh.py
@@ -1,14 +1,11 @@
 """Functions to handle mesh data and read it from file."""
 from collections.abc import Callable
 from pathlib import Path
-from typing import TypeAlias
 
 import numpy as np
-import numpy.typing as npt
 import trimesh
 
-# Abstraction for the mesh type.
-Mesh: TypeAlias = trimesh.Trimesh
+from readyplayerme.meshops.types import Edges, Indices, Mesh
 
 
 def read_mesh(filename: str | Path) -> Mesh:
@@ -24,27 +21,29 @@ def read_mesh(filename: str | Path) -> Mesh:
 def get_mesh_reader(filename: str | Path) -> Callable[[str | Path], Mesh]:
     """Return a reader function for a given file extension."""
     if (ext := Path(filename).suffix) in [".glb", ".gltf"]:
-        return read_glb
+        return read_gltf
     msg = f"Unsupported file format: {ext}"
     raise NotImplementedError(msg)
 
 
-def read_glb(filename: str | Path) -> Mesh:
-    """Load 3D model data from a GLB file into a Mesh representation.
+def read_gltf(filename: str | Path) -> Mesh:
+    """Load 3D model data from a glTF file into a Mesh representation.
 
-    :param filename: The path to the GLB file to be loaded.
+    :param filename: The path to the glTF file to be loaded.
     :return: The loaded mesh object.
     """
     return trimesh.load(filename, process=False, force="mesh")
 
 
-def get_border_vertices(mesh: Mesh) -> npt.NDArray[np.int64]:
-    """Return the indices of the vertices on the borders of a mesh.
+def get_boundary_vertices(edges: Edges) -> Indices:
+    """Return the indices of the vertices on the mesh boundary.
 
-    :param mesh: The mesh to get the border vertices from.
-    :return: The indices of the border vertices.
+    A boundary edge is an edge that only belongs to a single triangle.
+
+    :param edges: The edges of the mesh. Must include all edges by faces (duplicates).
+    :return: Vertex indices on mesh boundary.
     """
-    edges = mesh.edges_sorted
-    unique_edges, edge_triangle_count = np.unique(edges, return_counts=True, axis=0)
+    sorted_edges = np.sort(edges, axis=1)
+    unique_edges, edge_triangle_count = np.unique(sorted_edges, return_counts=True, axis=0)
     border_edge_indices = np.where(edge_triangle_count == 1)[0]
     return np.unique(unique_edges[border_edge_indices])
diff --git a/src/readyplayerme/meshops/types.py b/src/readyplayerme/meshops/types.py
new file mode 100644
index 0000000..aee2060
--- /dev/null
+++ b/src/readyplayerme/meshops/types.py
@@ -0,0 +1,22 @@
+"""Custom types for meshops."""
+from typing import Protocol, TypeAlias
+
+import numpy as np
+import numpy.typing as npt
+
+# trimesh uses int64 and float64 for its arrays.
+Indices: TypeAlias = npt.NDArray[np.int32] | npt.NDArray[np.int64]  # Shape (i,)
+Vertices: TypeAlias = npt.NDArray[np.float32] | npt.NDArray[np.float64]  # Shape (v, 3)
+Edges: TypeAlias = npt.NDArray[np.int32] | npt.NDArray[np.int64]  # Shape (e, 2)
+Faces: TypeAlias = npt.NDArray[np.int32] | npt.NDArray[np.int64]  # Shape (f, 3)
+
+
+class Mesh(Protocol):
+    """Structural type for a mesh class.
+
+    Any class considered a mesh must structurally be compatible with this protocol.
+    """
+
+    vertices: Vertices
+    edges: Edges
+    faces: Faces
diff --git a/tests/conftest.py b/tests/conftest.py
index 5e2448b..c072230 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1,3 +1,4 @@
+"""Pytest fixtures for the whole repo."""
 from pathlib import Path
 
 import pytest
diff --git a/tests/mocks/__init__.py b/tests/mocks/__init__.py
new file mode 100644
index 0000000..5e09a08
--- /dev/null
+++ b/tests/mocks/__init__.py
@@ -0,0 +1 @@
+"""Module holding data-files for resource mocks."""
diff --git a/tests/readyplayerme/meshops/conftest.py b/tests/readyplayerme/meshops/conftest.py
new file mode 100644
index 0000000..442c6eb
--- /dev/null
+++ b/tests/readyplayerme/meshops/conftest.py
@@ -0,0 +1,12 @@
+"""Pytest fixtures for meshops tests."""
+import pytest
+
+
+@pytest.fixture
+def gltf_simple_file():
+    """Return a path to a simple glTF file."""
+    from importlib.resources import files
+
+    import tests.mocks
+
+    return files(tests.mocks).joinpath("uv-seams.glb")
diff --git a/tests/readyplayerme/meshops/integration/test_integration.py b/tests/readyplayerme/meshops/integration/test_integration.py
new file mode 100644
index 0000000..323ae6e
--- /dev/null
+++ b/tests/readyplayerme/meshops/integration/test_integration.py
@@ -0,0 +1,15 @@
+from pathlib import Path
+
+import numpy as np
+
+import readyplayerme.meshops.mesh as mops
+
+
+def test_boundary_vertices_from_file(gltf_simple_file: str | Path):
+    """Test the integration of extracting mesh boundary vertices from a file."""
+    local_mesh = mops.read_mesh(gltf_simple_file)
+    edges = local_mesh.edges
+    boundary_vertices = mops.get_boundary_vertices(edges)
+    assert np.array_equiv(
+        np.sort(boundary_vertices), [0, 2, 4, 6, 7, 9, 10]
+    ), "The vertices returned by get_border_vertices do not match the expected vertices."
diff --git a/tests/readyplayerme/meshops/test_mesh.py b/tests/readyplayerme/meshops/test_mesh.py
deleted file mode 100644
index 0287e3b..0000000
--- a/tests/readyplayerme/meshops/test_mesh.py
+++ /dev/null
@@ -1,25 +0,0 @@
-"""Unit tests for the mesh module."""
-from pathlib import Path
-
-from readyplayerme.meshops import mesh
-
-mocks_path = Path(__file__).parent.parent.parent / "mocks"
-
-
-def test_read_glb():
-    """Test the read_glb function returns the expected type."""
-    filename = mocks_path / "input-mesh.glb"
-    result = mesh.read_glb(filename)
-    assert isinstance(result, mesh.Mesh), "The result should be an instance of mesh.Mesh"
-
-
-def test_border_vertices():
-    """Test the get_border_vertices function returns the expected indices."""
-    import numpy as np
-
-    # TODO: create a fixture for loading the file, or mock it, loading the mesh should not be part of the test!
-    filename = mocks_path / "uv-seams.glb"
-    geo = mesh.read_glb(filename)
-    border_vertices = mesh.get_border_vertices(geo)
-
-    assert np.array_equiv(np.sort(border_vertices), [0, 2, 4, 6, 7, 9, 10])
diff --git a/tests/readyplayerme/meshops/unit/conftest.py b/tests/readyplayerme/meshops/unit/conftest.py
new file mode 100644
index 0000000..fc9f008
--- /dev/null
+++ b/tests/readyplayerme/meshops/unit/conftest.py
@@ -0,0 +1,94 @@
+"""Pytest fixtures for meshops unit tests."""
+from dataclasses import dataclass
+
+import numpy as np
+import numpy.typing as npt
+import pytest
+
+
+@pytest.fixture
+def mock_mesh():
+    """Return a mocked instance of a mesh."""
+
+    @dataclass
+    class MockMesh:
+        vertices: npt.NDArray[np.float32]
+        edges: npt.NDArray[np.int32]
+        faces: npt.NDArray[np.int32]
+
+    vertices = np.array(
+        [
+            [-1.0, -1.0, 1.0],
+            [-1.0, 1.0, 1.0],
+            [-1.0, -1.0, -1.0],
+            [-1.0, 1.0, -1.0],
+            [1.0, -1.0, 1.0],
+            [1.0, 1.0, 1.0],
+            [1.0, -1.0, -1.0],
+            [1.0, 1.0, -1.0],
+            [1.0, 0.0, 1.0],
+            [1.0, 0.0, -1.0],
+            [1.0, 0.0, -1.0],
+        ]
+    )
+    edges = np.array(
+        [
+            [9, 2],
+            [2, 3],
+            [3, 9],
+            [3, 7],
+            [7, 9],
+            [9, 3],
+            [7, 8],
+            [8, 10],
+            [10, 7],
+            [8, 5],
+            [5, 1],
+            [1, 8],
+            [3, 5],
+            [5, 7],
+            [7, 3],
+            [1, 2],
+            [2, 0],
+            [0, 1],
+            [3, 1],
+            [1, 5],
+            [5, 3],
+            [9, 6],
+            [6, 2],
+            [2, 9],
+            [1, 3],
+            [3, 2],
+            [2, 1],
+            [7, 5],
+            [5, 8],
+            [8, 7],
+            [8, 0],
+            [0, 4],
+            [4, 8],
+            [10, 8],
+            [8, 4],
+            [4, 10],
+            [8, 1],
+            [1, 0],
+            [0, 8],
+        ]
+    )
+    faces = np.array(
+        [
+            [9, 2, 3],
+            [3, 7, 9],
+            [7, 8, 10],
+            [8, 5, 1],
+            [3, 5, 7],
+            [1, 2, 0],
+            [3, 1, 5],
+            [9, 6, 2],
+            [1, 3, 2],
+            [7, 5, 8],
+            [8, 0, 4],
+            [10, 8, 4],
+            [8, 1, 0],
+        ]
+    )
+    return MockMesh(vertices=vertices, edges=edges, faces=faces)
diff --git a/tests/readyplayerme/meshops/unit/test_mesh.py b/tests/readyplayerme/meshops/unit/test_mesh.py
new file mode 100644
index 0000000..eaaa655
--- /dev/null
+++ b/tests/readyplayerme/meshops/unit/test_mesh.py
@@ -0,0 +1,59 @@
+"""Unit tests for the mesh module."""
+import types
+from collections.abc import Callable
+from pathlib import Path
+from typing import Union, get_args, get_origin
+
+import numpy as np
+import pytest
+
+from readyplayerme.meshops import mesh
+from readyplayerme.meshops.types import Mesh
+
+
+class TestReadMesh:
+    """Test suite for the mesh reader functions."""
+
+    @pytest.mark.parametrize(
+        "filepath, expected",
+        [("test.glb", mesh.read_gltf), (Path("test.glb"), mesh.read_gltf), ("test.gltf", mesh.read_gltf)],
+    )
+    def test_get_mesh_reader_glb(self, filepath: str | Path, expected: Callable[[str | Path], Mesh]):
+        """Test the get_mesh_reader function with a .glb file path."""
+        reader = mesh.get_mesh_reader(filepath)
+        assert callable(reader), "The mesh reader should be a callable function."
+        assert reader == expected, "The reader function for .glTF files should be read_gltf."
+
+    @pytest.mark.parametrize("filepath", ["test", "test.obj", Path("test.stl"), "test.fbx", "test.abc", "test.ply"])
+    def test_get_mesh_reader_unsupported(self, filepath: str | Path):
+        """Test the get_mesh_reader function with an unsupported file format."""
+        with pytest.raises(NotImplementedError):
+            mesh.get_mesh_reader(filepath)
+
+    def test_read_mesh_gltf(self, gltf_simple_file: str | Path):
+        """Test the read_gltf function returns the expected type."""
+        result = mesh.read_gltf(gltf_simple_file)
+        # Check the result has all the expected attributes and of the correct type.
+        for attr in Mesh.__annotations__:
+            assert hasattr(result, attr), f"The mesh class should have a '{attr}' attribute."
+            # Find the type so we can use it as a second argument to isinstance.
+            tp = get_origin(Mesh.__annotations__[attr])
+            if tp is Union or tp is types.UnionType:
+                tp = get_args(Mesh.__annotations__[attr])
+                # Loop through the types in the union and check if the result is compatible with any of them.
+                assert any(
+                    isinstance(getattr(result, attr), get_origin(t)) for t in tp
+                ), f"The '{attr}' attribute should be compatible with {tp}."
+            else:
+                assert isinstance(
+                    getattr(result, attr), tp
+                ), f"The '{attr}' attribute should be compatible with {Mesh.__annotations__[attr]}."
+
+
+def test_get_boundary_vertices(mock_mesh: Mesh):
+    """Test the get_boundary_vertices function returns the expected indices."""
+    boundary_vertices = mesh.get_boundary_vertices(mock_mesh.edges)
+
+    assert np.array_equiv(
+        np.sort(boundary_vertices), [0, 2, 4, 6, 7, 9, 10]
+    ), "The vertices returned by get_border_vertices do not match the expected vertices."