diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index a1a724f59..b47f73443 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -15,6 +15,10 @@ jobs:
     strategy:
       matrix:
         include:
+          - python-version: "3.14.0-alpha.1"
+            with-opt-deps: true
+            runs-on: ubuntu-22.04
+
           - python-version: "3.13.0"
             with-opt-deps: true
             runs-on: ubuntu-22.04
diff --git a/src/callbacks.py b/src/callbacks.py
index e3772c81b..69eea38c0 100644
--- a/src/callbacks.py
+++ b/src/callbacks.py
@@ -1355,12 +1355,8 @@ class CommandProcess(world.SupyProcess):
                                                  pn,
                                                  cn)
         log.debug('Spawning process %s (args: %r)', procName, args)
-        self.__parent = super(CommandProcess, self)
-        self.__parent.__init__(target=target, name=procName,
-                               args=args, kwargs=kwargs)
-
-    def run(self):
-        self.__parent.run()
+        super().__init__(target=target, name=procName,
+                         args=args, kwargs=kwargs)
 
 class CanonicalString(registry.NormalizedString):
     def normalize(self, s):
diff --git a/src/commands.py b/src/commands.py
index 7c11ff5d2..c57e75fe2 100644
--- a/src/commands.py
+++ b/src/commands.py
@@ -88,6 +88,20 @@ def _rlimit_min(a, b):
     else:
         return min(soft, heap_size)
 
+def _process_target(f, q, heap_size, *args, **kwargs):
+    """Called by :func:`process`"""
+    if resource:
+        rsrc = resource.RLIMIT_DATA
+        (soft, hard) = resource.getrlimit(rsrc)
+        soft = _rlimit_min(soft, heap_size)
+        hard = _rlimit_min(hard, heap_size)
+        resource.setrlimit(rsrc, (soft, hard))
+    try:
+        r = f(*args, **kwargs)
+        q.put([False, r])
+    except Exception as e:
+        q.put([True, e])
+
 def process(f, *args, **kwargs):
     """Runs a function <f> in a subprocess.
     
@@ -122,21 +136,9 @@ def process(f, *args, **kwargs):
                 '(See https://github.com/travis-ci/travis-core/issues/187\n'
                 'for more information about this bug.)\n')
         raise
-    def newf(f, q, *args, **kwargs):
-        if resource:
-            rsrc = resource.RLIMIT_DATA
-            (soft, hard) = resource.getrlimit(rsrc)
-            soft = _rlimit_min(soft, heap_size)
-            hard = _rlimit_min(hard, heap_size)
-            resource.setrlimit(rsrc, (soft, hard))
-        try:
-            r = f(*args, **kwargs)
-            q.put([False, r])
-        except Exception as e:
-            q.put([True, e])
-    targetArgs = (f, q,) + args
-    p = callbacks.CommandProcess(target=newf,
-                                args=targetArgs, kwargs=kwargs)
+    targetArgs = (f, q, heap_size) + args
+    p = callbacks.CommandProcess(target=_process_target,
+                                 args=targetArgs, kwargs=kwargs)
     try:
         p.start()
     except OSError as e:
diff --git a/src/utils/math_evaluator.py b/src/utils/math_evaluator.py
index b7ef34027..ff04009ab 100644
--- a/src/utils/math_evaluator.py
+++ b/src/utils/math_evaluator.py
@@ -154,8 +154,16 @@ class SafeEvalVisitor(ast.NodeVisitor):
         return self.visit(node.body)
 
     def visit_Num(self, node):
+        """Python < 3.14 only"""
         return self._convert_num(node.n)
 
+    def visit_Constant(self, node):
+        """Python >= 3.14 only"""
+        if type(node.value) in (float, complex, int):
+            return self._convert_num(node.value)
+        else:
+            raise InvalidNode('illegal constant %s' % node.value)
+
     def visit_Name(self, node):
         id_ = node.id.lower()
         if id_ in self._env:
diff --git a/src/utils/str.py b/src/utils/str.py
index c9a86c21e..5fe7ae943 100644
--- a/src/utils/str.py
+++ b/src/utils/str.py
@@ -307,9 +307,9 @@ def perlReToReplacer(s):
         flags = ''.join(flags)
     r = perlReToPythonRe(sep.join(('', regexp, flags)))
     if g:
-        return lambda s: r.sub(replace, s)
+        return functools.partial(r.sub, replace)
     else:
-        return lambda s: r.sub(replace, s, 1)
+        return functools.partial(r.sub, replace, count=1)
 
 _perlVarSubstituteRe = re.compile(r'\$\{([^}]+)\}|\$([a-zA-Z][a-zA-Z0-9]*)')
 def perlVariableSubstitute(vars, text):
diff --git a/src/world.py b/src/world.py
index 85f581ec5..75f994682 100644
--- a/src/world.py
+++ b/src/world.py
@@ -65,7 +65,7 @@ class SupyThread(threading.Thread, object):
         log.debug('Spawning thread %q.', self.getName())
 
 processesSpawned = 1 # Starts at one for the initial process.
-class SupyProcess(multiprocessing.Process):
+class SupyProcess(multiprocessing.get_context('fork').Process):
     def __init__(self, *args, **kwargs):
         global processesSpawned
         processesSpawned += 1