diff --git a/nix/sources.json b/nix/sources.json
index 50ff572..e404a28 100644
--- a/nix/sources.json
+++ b/nix/sources.json
@@ -1,26 +1,14 @@
 {
-    "nix-build-uncached": {
-        "branch": "master",
-        "description": "A CI friendly wrapper around nix-build.",
-        "homepage": "",
-        "owner": "Mic92",
-        "repo": "nix-build-uncached",
-        "rev": "77fe5c8c4c5c7a1fa3f9baa042474b98f2456652",
-        "sha256": "04hqiw3rhz01qqyz2x1q14aml1ifk3m97pldf4v5vhd5hg73k1zn",
-        "type": "tarball",
-        "url": "https://github.com/Mic92/nix-build-uncached/archive/77fe5c8c4c5c7a1fa3f9baa042474b98f2456652.tar.gz",
-        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
-    },
     "nixpkgs": {
         "branch": "nixos-unstable",
         "description": "A read-only mirror of NixOS/nixpkgs tracking the released channels. Send issues and PRs to",
         "homepage": "https://github.com/NixOS/nixpkgs",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "ce8cbe3c01fd8ee2de526ccd84bbf9b82397a510",
-        "sha256": "19xfad7pxsp6nkrkjhn36w77w92m60ysq7njn711slw74yj6ibxv",
+        "rev": "ff9efb0724de5ae0f9db9df2debefced7eb1571d",
+        "sha256": "188h461pilsiym2dqzl17vx1g9pb816cwdi0az9mbw207w721avz",
         "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/ce8cbe3c01fd8ee2de526ccd84bbf9b82397a510.tar.gz",
+        "url": "https://github.com/NixOS/nixpkgs/archive/ff9efb0724de5ae0f9db9df2debefced7eb1571d.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     }
 }
diff --git a/overrides/build-systems.json b/overrides/build-systems.json
index ba5b12f..68b0a20 100644
--- a/overrides/build-systems.json
+++ b/overrides/build-systems.json
@@ -29,6 +29,9 @@
   "aioflo": [
     "poetry-core"
   ],
+  "aiogithubapi": [
+    "poetry-core"
+  ],
   "aioguardian": [
     "poetry-core"
   ],
@@ -89,9 +92,18 @@
   "amqtt": [
     "poetry-core"
   ],
+  "ansible-doctor": [
+    "poetry-core"
+  ],
+  "ansible-later": [
+    "poetry-core"
+  ],
   "apache-beam": [
     "cython"
   ],
+  "aplpy": [
+    "cython"
+  ],
   "argon2_cffi": [
     "flitBuildHook"
   ],
@@ -120,6 +132,9 @@
   "authcaptureproxy": [
     "poetry-core"
   ],
+  "av": [
+    "cython"
+  ],
   "awesomeversion": [
     "poetry-core"
   ],
@@ -147,6 +162,9 @@
   "boltztrap2": [
     "cython"
   ],
+  "bsblan": [
+    "poetry-core"
+  ],
   "build": [
     "flit-core"
   ],
@@ -210,7 +228,8 @@
     "poetry-core"
   ],
   "cssselect2": [
-    "flit"
+    "flit",
+    "flit-core"
   ],
   "cwcwidth": [
     "cython"
@@ -301,7 +320,8 @@
     "poetry-core"
   ],
   "entrypoints": [
-    "flit"
+    "flit",
+    "flit-core"
   ],
   "enturclient": [
     "poetry-core"
@@ -728,6 +748,9 @@
   "openvino": [
     "cython"
   ],
+  "ordered-set": [
+    "flit-core"
+  ],
   "ormar": [
     "poetry-core"
   ],
@@ -1221,7 +1244,8 @@
     "poetry-core"
   ],
   "rokuecp": [
-    "poetry"
+    "poetry",
+    "poetry-core"
   ],
   "roombapy": [
     "poetry-core"
@@ -1307,6 +1331,9 @@
   "slowapi": [
     "poetry-core"
   ],
+  "socksio": [
+    "flit-core"
+  ],
   "solo-python": [
     "flitBuildHook"
   ],
@@ -1431,7 +1458,8 @@
     "cython"
   ],
   "testpath": [
-    "flit"
+    "flit",
+    "flit-core"
   ],
   "testrepository": [
     "pbr"
diff --git a/overrides/default.nix b/overrides/default.nix
index de03ce8..42b2485 100644
--- a/overrides/default.nix
+++ b/overrides/default.nix
@@ -437,6 +437,17 @@ lib.composeManyExtensions [
         }
       );
 
+      # Setuptools >= 60 broke build_py_2to3
+      docutils =
+        if lib.versionOlder super.docutils.version "0.16" && lib.versionAtLeast super.setuptools.version "60" then
+          (
+            super.docutils.overridePythonAttrs (
+              old: {
+                SETUPTOOLS_USE_DISTUTILS = "stdlib";
+              }
+            )
+          ) else super.docutils;
+
       # Environment markers are not always included (depending on how a dep was defined)
       enum34 = if self.pythonAtLeast "3.4" then null else super.enum34;
 
diff --git a/shell.nix b/shell.nix
index e129931..b3498c6 100644
--- a/shell.nix
+++ b/shell.nix
@@ -7,10 +7,6 @@ let
   };
   tools = pkgs.callPackage ./tools { };
 
-  nix-build-uncached = import sources.nix-build-uncached {
-    inherit pkgs;
-  };
-
 in
 pkgs.mkShell {
 
@@ -27,6 +23,6 @@ pkgs.mkShell {
     pkgs.jq
     pkgs.nix-prefetch-git
     pkgs.nix-eval-jobs
-    nix-build-uncached
+    pkgs.nix-build-uncached
   ];
 }