diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7a7654a..6e5cb3c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,10 +10,13 @@ on:
 
 jobs:
   scala:
-    runs-on: ubuntu-latest
     strategy:
       matrix:
         JDK: [ 8, 17 ]
+        os:
+          - ubuntu-latest
+          - windows-latest
+    runs-on: ${{ matrix.os }}
 
     steps:
       - name: checkout the repo
diff --git a/src/main/scala/org/scoverage/coveralls/CoberturaMultiSourceReader.scala b/src/main/scala/org/scoverage/coveralls/CoberturaMultiSourceReader.scala
index 084871b..259a314 100644
--- a/src/main/scala/org/scoverage/coveralls/CoberturaMultiSourceReader.scala
+++ b/src/main/scala/org/scoverage/coveralls/CoberturaMultiSourceReader.scala
@@ -114,7 +114,7 @@ class CoberturaMultiSourceReader(
 
   protected def lineCoverage(sourceFile: String) = {
     val filenamePath =
-      splitPath(new File(sourceFile))._2.replace(File.separator, "/")
+      splitPath(new File(sourceFile))._2
 
     lineCoverageMap(filenamePath)
   }