diff --git a/jaxtyping/_import_hook.py b/jaxtyping/_import_hook.py
index 21cca35..0aec718 100644
--- a/jaxtyping/_import_hook.py
+++ b/jaxtyping/_import_hook.py
@@ -51,6 +51,7 @@
 
 import ast
 import functools as ft
+import hashlib
 import sys
 from collections.abc import Sequence
 from importlib.abc import MetaPathFinder
@@ -165,7 +166,9 @@ class _JaxtypingLoader(SourceFileLoader):
     def __init__(self, *args, typechecker, **kwargs):
         super().__init__(*args, **kwargs)
         self._typechecker = typechecker
-        self._typechecker_hash = str(abs(hash(self._typechecker)))
+        self._typechecker_hash = hashlib.md5(
+            self._typechecker.encode("utf-8")
+        ).hexdigest()
 
     def source_to_code(self, data, path, *, _optimize=-1):
         source = decode_source(data)
diff --git a/pyproject.toml b/pyproject.toml
index 168d3ae..66a316b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "jaxtyping"
-version = "0.2.20"
+version = "0.2.21"
 description = "Type annotations and runtime checking for shape and dtype of JAX arrays, and PyTrees."
 readme = "README.md"
 requires-python ="~=3.9"