diff --git a/.gitignore b/.gitignore
index 10141fd..106b858 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,4 +9,5 @@ config/supervisord.conf
 config/supervisord-conf-vars.conf
 config/logging.json
 
+/.tox
 result
diff --git a/flake.lock b/flake.lock
index 42c1c75..f608745 100644
--- a/flake.lock
+++ b/flake.lock
@@ -8,11 +8,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1700943598,
-        "narHash": "sha256-zTY0h/7Z3oMFIUSj3ZQ/h1dvruAGwEAQF/24TI7VSGA=",
+        "lastModified": 1701445174,
+        "narHash": "sha256-H9TtAirAUCnDCgoYGwqU1lWro1O5JVQPfy/neHR4Szk=",
         "owner": "Stowarzyszenie-Talent",
         "repo": "filetracker",
-        "rev": "aa5e2c2397f68e12ba966d5665ec9a08b552d3bd",
+        "rev": "0e4fc26352e46e8beb325812c433e6080a8fc7e1",
         "type": "github"
       },
       "original": {
@@ -59,16 +59,16 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1699646590,
-        "narHash": "sha256-f81xS0qN6H1ULTyArpZgdjsly4FY0BnvPXdmSb7hq+o=",
+        "lastModified": 1701444729,
+        "narHash": "sha256-XO5N4pNawFTN+OqFbA2SXCFZoGQvpb0rlmkNeE4qTYA=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "1d55765508b8316798429875712dc1ef5e62a2fa",
+        "rev": "8ce27dc770aabf044910fe18cde1a88e740af6f3",
         "type": "github"
       },
       "original": {
         "owner": "NixOS",
-        "ref": "release-23.05",
+        "ref": "release-23.11",
         "repo": "nixpkgs",
         "type": "github"
       }
diff --git a/flake.nix b/flake.nix
index e854aff..b0d647e 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,6 +1,6 @@
 {
   description = "The task runner used by SIO2";
-  inputs.nixpkgs.url = "github:NixOS/nixpkgs/release-23.05";
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/release-23.11";
   inputs.flake-utils.url = "github:numtide/flake-utils";
   inputs.filetracker = {
     url = "github:Stowarzyszenie-Talent/filetracker";
diff --git a/nix/package.nix b/nix/package.nix
index cc76841..a4b47e9 100644
--- a/nix/package.nix
+++ b/nix/package.nix
@@ -31,11 +31,22 @@ buildPythonPackage {
   };
 
   doCheck = false;
+  NO_JAVA_TESTS = "1";
+  #TEST_SANDBOXES = "1"; # These are broken anyway, `supervisor` moment.
+  # Doesn't set correctly without this for some reason.
+  LOCALE_ARCHIVE = "${pkgs.glibcLocales}/lib/locale/locale-archive";
 
+  # Only for tests
   nativeBuildInputs = [
     pytest
     pytest-runner
     pytest-timeout
+    pkgs.gcc pkgs.fpc
+  ];
+
+  # Only for tests
+  buildInputs = [
+    pkgs.glibc.static
   ];
 
   propagatedBuildInputs = [
@@ -48,4 +59,3 @@ buildPythonPackage {
     bsddb3
   ];
 }
-
diff --git a/setup.py b/setup.py
index 91c4a01..bf72163 100644
--- a/setup.py
+++ b/setup.py
@@ -18,15 +18,15 @@
         'bsddb3<6.3',
         'simplejson<3.20',
         #'supervisor>=4.0,<4.3',
-        'Twisted<22.11',
+        'Twisted>=23.8,<23.9',
         'sortedcontainers<2.5',
         'six<1.17',
-        'urllib3<1.27',
+        'urllib3>=2.0,<2.1',
     ],
 
     extras_require = {
         'dev' : [
-            'pytest<7.3',
+            'pytest<8',
             'pytest-timeout<2.2',
             'tox',
         ]