diff --git a/nix/nixpkgs-version.nix b/nix/nixpkgs-version.nix
index 698225df2..9500eb9a7 100644
--- a/nix/nixpkgs-version.nix
+++ b/nix/nixpkgs-version.nix
@@ -1,6 +1,6 @@
 # Pinned version of Nixpkgs, generated with postgrest-nixpkgs-upgrade.
 {
-  date = "2023-01-12";
-  rev = "92f9580a4c369b4b51a7b6a5e77da43720134c9f";
-  tarballHash = "0w9bz4f2bmkj4a59n4z279zcgs9clyc40a4ny312rafyaknzghvw";
+  date = "2023-03-25";
+  rev = "dbf5322e93bcc6cfc52268367a8ad21c09d76fea";
+  tarballHash = "0lwk4v9dkvd28xpqch0b0jrac4xl9lwm6snrnzx8k5lby72kmkng";
 }
diff --git a/test/io/postgrest.py b/test/io/postgrest.py
index 2a8745f11..bd25c4c47 100644
--- a/test/io/postgrest.py
+++ b/test/io/postgrest.py
@@ -143,7 +143,7 @@ def wait_until_exit(postgrest):
     "Wait for PostgREST to exit, or times out"
     try:
         return postgrest.process.wait(timeout=1)
-    except (subprocess.TimeoutExpired):
+    except subprocess.TimeoutExpired:
         raise PostgrestTimedOut()
 
 
diff --git a/test/io/test_io.py b/test/io/test_io.py
index fdaf87e08..a33a9c34b 100644
--- a/test/io/test_io.py
+++ b/test/io/test_io.py
@@ -535,7 +535,6 @@ def test_pool_size(defaultenv, metapostgrest):
     }
 
     with run(env=env) as postgrest:
-
         start = time.time()
         threads = []
         for i in range(4):
@@ -672,7 +671,6 @@ def test_admin_ready_includes_schema_cache_state(defaultenv, metapostgrest):
     }
 
     with run(env=env) as postgrest:
-
         # make it impossible to load the schema cache, by setting statement timeout to 1ms
         set_statement_timeout(metapostgrest, role, 1)
 
@@ -728,7 +726,6 @@ def test_admin_works_with_host_special_values(specialhostvalue, defaultenv):
     "Should get a success from the admin live and ready endpoints when using special host values for the main app"
 
     with run(env=defaultenv, port=freeport(), host=specialhostvalue) as postgrest:
-
         response = postgrest.admin.get("/live")
         assert response.status_code == 200
 
@@ -784,7 +781,6 @@ def test_no_pool_connection_required_on_bad_http_logic(defaultenv):
     "no pool connection should be consumed for failing on invalid http logic"
 
     with run(env=defaultenv, no_pool_connection_available=True) as postgrest:
-
         # not found nested route shouldn't require opening a connection
         response = postgrest.session.head("/path/notfound")
         assert response.status_code == 404
@@ -800,7 +796,6 @@ def test_no_pool_connection_required_on_options(defaultenv):
     "no pool connection should be consumed for OPTIONS requests"
 
     with run(env=defaultenv, no_pool_connection_available=True) as postgrest:
-
         # OPTIONS on a table shouldn't require opening a connection
         response = postgrest.session.options("/projects")
         assert response.status_code == 200
@@ -820,7 +815,6 @@ def test_no_pool_connection_required_on_bad_jwt_claim(defaultenv):
     env = {**defaultenv, "PGRST_JWT_SECRET": SECRET}
 
     with run(env=env, no_pool_connection_available=True) as postgrest:
-
         # A JWT with an invalid signature shouldn't open a connection
         headers = jwtauthheader({"role": "postgrest_test_author"}, "Wrong Secret")
         response = postgrest.session.get("/projects", headers=headers)
@@ -831,7 +825,6 @@ def test_no_pool_connection_required_on_bad_embedding(defaultenv):
     "no pool connection should be consumed for failing to embed"
 
     with run(env=defaultenv, no_pool_connection_available=True) as postgrest:
-
         # OPTIONS on a table shouldn't require opening a connection
         response = postgrest.session.get("/projects?select=*,unexistent(*)")
         assert response.status_code == 400
@@ -841,7 +834,6 @@ def test_notify_reloading_catalog_cache(defaultenv):
     "notify should reload the connection catalog cache"
 
     with run(env=defaultenv) as postgrest:
-
         # first the id col is an uuid
         response = postgrest.session.get(
             "/cats?id=eq.dea27321-f988-4a57-93e4-8eeb38f3cf1e"