diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index a1b2f8d78..eb23efe86 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -8,13 +8,38 @@ on:
     branches: [main]
 
 jobs:
-  build:
+  pre-commit:
     runs-on: ubuntu-latest
 
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 19.x
+          cache: "npm"
+
+      - name: Install Node dependencies
+        run: |
+          npm install
+
+      - name: Run pre-commit
+        uses: pre-commit/action@v3.0.1
+        with:
+          extra_args: --all-files --verbose --show-diff-on-failure
+
+  build:
+    runs-on: ${{ matrix.os }}
+
     strategy:
       matrix:
+        os: [windows-latest, ubuntu-latest]
         python-version: ["3.10", "3.12"]
         node-version: [19.x]
+        exclude:
+          - os: windows-latest
+            python-version: "3.10"
 
     steps:
       - uses: actions/checkout@v4
@@ -42,11 +67,6 @@ jobs:
       #   run: |
       #     npm install
 
-      - name: Run pre-commit
-        uses: pre-commit/action@v3.0.1
-        with:
-          extra_args: --all-files --verbose --show-diff-on-failure
-
       - name: Run Python tests with pytest
         run: |
           pytest -vv
diff --git a/src/fontra/backends/filenames.py b/src/fontra/backends/filenames.py
index e96d7bc39..a52ca3c4b 100644
--- a/src/fontra/backends/filenames.py
+++ b/src/fontra/backends/filenames.py
@@ -55,6 +55,10 @@ def stringToFileName(string: str) -> str:
     )
     if fileName[0] == ".":
         fileName = "%2E" + fileName[1:]
+    elif "." in fileName:
+        base, rest = fileName.split(".", 1)
+        if base.lower() in reservedFileNames:
+            fileName = base + "%2E" + rest
     if not codeDigits and fileName.lower() in reservedFileNames:
         codeDigits = [0]
     if codeDigits:
diff --git a/src/fontra/backends/fontra.py b/src/fontra/backends/fontra.py
index bf5c0147d..d706c0e71 100644
--- a/src/fontra/backends/fontra.py
+++ b/src/fontra/backends/fontra.py
@@ -189,7 +189,7 @@ async def putCustomData(self, customData: dict[str, Any]) -> None:
         self._scheduler.schedule(self._writeFontData)
 
     def _readGlyphInfo(self) -> None:
-        with self.glyphInfoPath.open("r", encoding="utf-8") as file:
+        with self.glyphInfoPath.open("r", encoding="utf-8", newline="") as file:
             reader = csv.reader(file, delimiter=";")
             header = next(reader)
             assert header[:2] == ["glyph name", "code points"]
@@ -202,7 +202,7 @@ def _readGlyphInfo(self) -> None:
                 self.glyphMap[glyphName] = codePoints
 
     def _writeGlyphInfo(self) -> None:
-        with self.glyphInfoPath.open("w", encoding="utf-8") as file:
+        with self.glyphInfoPath.open("w", encoding="utf-8", newline="") as file:
             writer = csv.writer(file, delimiter=";")
             writer.writerow(["glyph name", "code points"])
             for glyphName, codePoints in sorted(self.glyphMap.items()):
@@ -312,7 +312,7 @@ def serialize(data: list | dict) -> str:
 
 
 def writeKerningFile(path: pathlib.Path, kerning: dict[str, Kerning]) -> None:
-    with path.open("w", encoding="utf-8") as file:
+    with path.open("w", encoding="utf-8", newline="") as file:
         writer = csv.writer(file, delimiter=";")
 
         isFirst = True
@@ -346,7 +346,7 @@ class KerningParseError(Exception):
 def readKerningFile(path: pathlib.Path) -> dict[str, Kerning]:
     kerning = {}
 
-    with path.open("r", encoding="utf-8") as file:
+    with path.open("r", encoding="utf-8", newline="") as file:
         reader = csv.reader(file, delimiter=";")
         rowIter = iter(enumerate(reader, 1))
 
diff --git a/test-py/test_backends_designspace.py b/test-py/test_backends_designspace.py
index 69b766ba1..9b1b1400f 100644
--- a/test-py/test_backends_designspace.py
+++ b/test-py/test_backends_designspace.py
@@ -76,7 +76,7 @@ def writableTestFontSingleUFO(tmpdir):
 def readGLIFData(glyphName, ufoLayers):
     glyphSets = {layer.fontraLayerName: layer.glyphSet for layer in ufoLayers}
     return {
-        layerName: glyphSet.getGLIF(glyphName).decode("utf-8")
+        layerName: glyphSet.getGLIF(glyphName).decode("utf-8").replace("\r\n", "\n")
         for layerName, glyphSet in glyphSets.items()
         if glyphName in glyphSet
     }
diff --git a/test-py/test_backends_filenames.py b/test-py/test_backends_filenames.py
index 99d768824..f4361efe9 100644
--- a/test-py/test_backends_filenames.py
+++ b/test-py/test_backends_filenames.py
@@ -18,7 +18,12 @@
         ("CON", "CON^7"),
         ("con", "con^0"),
         ("aux", "aux^0"),
-        ("con.alt", "con.alt"),
+        ("con.alt", "con%2Ealt"),
+        ("conalt", "conalt"),
+        ("con.bbb.alt", "con%2Ebbb.alt"),
+        ("nul.alt", "nul%2Ealt"),
+        ("aux.alt", "aux%2Ealt"),
+        ("com1.alt", "com1%2Ealt"),
         ("a:", "a%3A"),
         ("A:", "A%3A^1"),
         ("a/", "a%2F"),
diff --git a/test-py/test_unicode_usedby_table.py b/test-py/test_unicode_usedby_table.py
index 708cbc502..932c3e598 100644
--- a/test-py/test_unicode_usedby_table.py
+++ b/test-py/test_unicode_usedby_table.py
@@ -7,6 +7,6 @@
 
 def test_unicode_usedBy_needs_update():
     try:
-        subprocess.run([scriptPath, "--check"], check=True)
+        subprocess.run(f"python {scriptPath} --check", check=True, shell=True)
     except subprocess.CalledProcessError:
         assert 0, f"unicode-utils.js is stale, please run ./scripts/{scriptPath.name}"