diff --git a/.github/workflows/run-tests.yml b/.github/workflows/run-tests.yml
index 3065514a1..213772d96 100644
--- a/.github/workflows/run-tests.yml
+++ b/.github/workflows/run-tests.yml
@@ -7,7 +7,6 @@ jobs:
       matrix:
         python-version:
           - '2.7'
-          - '3.5'
           - '3.6'
           - '3.7'
           - '3.8'
@@ -15,6 +14,7 @@ jobs:
           - '3.10'
           - '3.11'
           - '3.12'
+          - '3.13'
           - 'pypy-2.7'
           - 'pypy-3.6'
           - 'pypy-3.7'
@@ -24,9 +24,9 @@ jobs:
       fail-fast: false
     name: Python ${{ matrix.python-version }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Setup python
-        uses: MatteoH2O1999/setup-python@v2
+        uses: MatteoH2O1999/setup-python@v4
         with:
           python-version: ${{ matrix.python-version }}
           cache: pip
diff --git a/coconut/compiler/util.py b/coconut/compiler/util.py
index 1f8f1297d..196e98350 100644
--- a/coconut/compiler/util.py
+++ b/coconut/compiler/util.py
@@ -624,18 +624,24 @@ def with_start_marker(self):
         internal_assert(not CPYPARSING, "StartOfStrGrammar.with_start_marker() should only be necessary without cPyparsing")
         return self.start_marker + self.grammar
 
+    def apply(self, grammar_transformer):
+        """Apply a function to transform the grammar."""
+        self.grammar = grammar_transformer(self.grammar)
+
     @property
     def name(self):
         return get_name(self.grammar)
 
 
-def prep_grammar(grammar, for_scan, streamline=False):
+def prep_grammar(grammar, for_scan, streamline=False, unpack=False):
     """Prepare a grammar item to be used as the root of a parse."""
     if isinstance(grammar, StartOfStrGrammar):
         if for_scan:
             grammar = grammar.with_start_marker()
         else:
             grammar = grammar.grammar
+    if unpack:
+        grammar = add_action(grammar, unpack)
     grammar = trace(grammar)
     if streamline:
         grammar.streamlined = False
@@ -701,7 +707,7 @@ def transform(grammar, text, inner=None):
         grammar = grammar.grammar
         kwargs["maxStartLoc"] = 0
     with parsing_context(inner):
-        result = prep_grammar(add_action(grammar, unpack), for_scan=True).transformString(text, **kwargs)
+        result = prep_grammar(grammar, unpack=True, for_scan=True).transformString(text, **kwargs)
         if result == text:
             result = None
         return result
diff --git a/coconut/root.py b/coconut/root.py
index e5b901fca..5060cca35 100644
--- a/coconut/root.py
+++ b/coconut/root.py
@@ -26,7 +26,7 @@
 VERSION = "3.1.0"
 VERSION_NAME = None
 # False for release, int >= 1 for develop
-DEVELOP = 12
+DEVELOP = 13
 ALPHA = False  # for pre releases rather than post releases
 
 assert DEVELOP is False or DEVELOP >= 1, "DEVELOP must be False or an int >= 1"