diff --git a/gha_extract_shell_scripts.py b/gha_extract_shell_scripts.py
index 3f91acf..ec3ec9f 100755
--- a/gha_extract_shell_scripts.py
+++ b/gha_extract_shell_scripts.py
@@ -30,6 +30,7 @@ def sanitize(path):
         ")": "",
         "&": "",
         "$": "",
+        ":": "",
     }
     return path.translate(str.maketrans(replacements))
 
@@ -44,14 +45,14 @@ def process_workflow_file(workflow_path: Path, output_dir: Path, ignored_errors=
         workflow = yaml.safe_load(f)
     workflow_file = workflow_path.name
     # GHA allows workflow names to be defined as empty (e.g. `name:`)
-    workflow_name = sanitize(workflow.get("name") or workflow_path.stem)
+    workflow_name = workflow.get("name") or workflow_path.stem
     workflow_default_shell = workflow.get("defaults", {}).get("run", {}).get("shell")
     workflow_env = workflow.get("env", {})
     count = 0
     print(f"Processing {workflow_path} ({workflow_name})")
     for job_key, job in workflow.get("jobs", {}).items():
         # GHA allows job names to be defined as empty (e.g. `name:`)
-        job_name = sanitize(job.get("name") or job_key)
+        job_name = job.get("name") or job_key
         job_default_shell = (
             job.get("defaults", {}).get("run", {}).get("shell", workflow_default_shell)
         )
@@ -69,7 +70,8 @@ def process_workflow_file(workflow_path: Path, output_dir: Path, ignored_errors=
             # GHA allows step names to be defined as empty (e.g. `name:`)
             step_name = sanitize(step.get("name") or str(i + 1))
             script_path = (
-                output_dir / workflow_file / f"job={job_name}" / f"step={step_name}.sh"
+                output_dir / workflow_file / f"job={sanitize(job_name)}" /
+                f"step={sanitize(step_name)}.sh"
             )
             script_path.parent.mkdir(parents=True, exist_ok=True)
             with script_path.open("w") as f:
diff --git a/test/test_reference.py b/test/test_reference.py
index e3083e3..bdf23a8 100644
--- a/test/test_reference.py
+++ b/test/test_reference.py
@@ -9,13 +9,18 @@
 TEST_DIR = os.path.dirname(os.path.abspath(__file__))
 sys.path.append(os.path.dirname(TEST_DIR))
 
-from gha_extract_shell_scripts import process_workflow_file
+from gha_extract_shell_scripts import process_workflow_file, sanitize
 
 def clean(string):
     string = textwrap.dedent(string).rstrip()
     return [l + "\n" for l in string.split("\n")]
 
 
+class TestSanitize(unittest.TestCase):
+    def test_gha_expression(self):
+        self.assertEqual(sanitize("Reference test: ${{ matrix.test }}"), "Reference_test_{{_matrix.test_}}")
+
+
 class TestReferenceWorkflows(unittest.TestCase):
     def setUp(self):
         self.maxDiff = None