diff --git a/recipe/meta.json b/recipe/meta.json
index 7648cf9..327ae3a 100644
--- a/recipe/meta.json
+++ b/recipe/meta.json
@@ -13,7 +13,7 @@
       "netcdf4 ==1.7.*",
       "pandas-stubs",
       "pip",
-      "pyfakefs ==6.1.*",
+      "pyfakefs ==5.10.*",
       "pyproj ==3.7.*",
       "pytest ==9.0.*",
       "pytest-cov ==7.0.*",
diff --git a/recipe/meta.yaml b/recipe/meta.yaml
index 5360707..c328684 100644
--- a/recipe/meta.yaml
+++ b/recipe/meta.yaml
@@ -36,7 +36,7 @@ test:
     - make 4.4.*
     - mypy 1.19.*
     - pandas-stubs
-    - pyfakefs 6.1.*
+    - pyfakefs 5.10.* # undiagnosed race-condition test failure observed with 6.1.*
     - pytest 9.0.*
     - pytest-cov 7.0.*
     - pytest-randomly 3.15.*