diff --git a/flake.lock b/flake.lock
index dbee101..02eebbb 100644
--- a/flake.lock
+++ b/flake.lock
@@ -4,18 +4,18 @@
       "inputs": {
         "artiq-comtools": "artiq-comtools",
         "mozilla-overlay": "mozilla-overlay",
-        "nixpkgs": "nixpkgs",
-        "sipyco": "sipyco",
+        "nixpkgs": "nixpkgs_3",
+        "sipyco": "sipyco_2",
         "src-migen": "src-migen",
         "src-misoc": "src-misoc",
         "src-pythonparser": "src-pythonparser"
       },
       "locked": {
-        "lastModified": 1649326693,
-        "narHash": "sha256-kWpSY+sJPr+T4P+aAVmElzd3qff1a+lQQ8YaCves6ic=",
+        "lastModified": 1649496284,
+        "narHash": "sha256-pI5PisI1OZLREEOpaUJjGlPRO8bz9bwXvP/RodtnWHU=",
         "ref": "master",
-        "rev": "386391e3f9500fc62b594f0a52f80f2daac73e36",
-        "revCount": 8026,
+        "rev": "0a029748eedb0778ba5a9598ec230458f921cf1a",
+        "revCount": 8027,
         "type": "git",
         "url": "https://github.com/m-labs/artiq.git"
       },
@@ -26,21 +26,15 @@
     },
     "artiq-comtools": {
       "inputs": {
-        "nixpkgs": [
-          "artiq",
-          "nixpkgs"
-        ],
-        "sipyco": [
-          "artiq",
-          "sipyco"
-        ]
+        "nixpkgs": "nixpkgs",
+        "sipyco": "sipyco"
       },
       "locked": {
-        "lastModified": 1647688999,
-        "narHash": "sha256-K99rYlmfCZmfam4m07hLZVg7m2zT5ul62wVGdpmjciA=",
+        "lastModified": 1649124276,
+        "narHash": "sha256-l1+vk7cvj4cjl83wRx/y1Jwdds4e8xAzpxHrXusEZ5A=",
         "owner": "m-labs",
         "repo": "artiq-comtools",
-        "rev": "7eb367b2df7510dd4fa7ccba3682b2ff64a5d982",
+        "rev": "e2d85f2e51ecdac463da752ef754e59572f9e119",
         "type": "github"
       },
       "original": {
@@ -99,11 +93,59 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1647490331,
-        "narHash": "sha256-Jcc+vHNDN3KDWuzGNTl3A24ICGovPneJDejiN2t57QI=",
+        "lastModified": 1649313840,
+        "narHash": "sha256-d23rAnhL08BCc88PxWAhEs/D+Kz3fMW2OTGDXWZSFMI=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "2c66a7a6e036971c4847cca424125f55b9eb0b0b",
+        "rev": "e387bb3a4d0d63446086abbfbe2117e80fe3522a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-21.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1649313840,
+        "narHash": "sha256-d23rAnhL08BCc88PxWAhEs/D+Kz3fMW2OTGDXWZSFMI=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "e387bb3a4d0d63446086abbfbe2117e80fe3522a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-21.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_3": {
+      "locked": {
+        "lastModified": 1649313840,
+        "narHash": "sha256-d23rAnhL08BCc88PxWAhEs/D+Kz3fMW2OTGDXWZSFMI=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "e387bb3a4d0d63446086abbfbe2117e80fe3522a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-21.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_4": {
+      "locked": {
+        "lastModified": 1649313840,
+        "narHash": "sha256-d23rAnhL08BCc88PxWAhEs/D+Kz3fMW2OTGDXWZSFMI=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "e387bb3a4d0d63446086abbfbe2117e80fe3522a",
         "type": "github"
       },
       "original": {
@@ -122,17 +164,32 @@
     },
     "sipyco": {
       "inputs": {
-        "nixpkgs": [
-          "artiq",
-          "nixpkgs"
-        ]
+        "nixpkgs": "nixpkgs_2"
       },
       "locked": {
-        "lastModified": 1647688038,
-        "narHash": "sha256-IceTSKu1sQB8sFmDTzvmurlEHWL1cV29N0mUY5F7vUY=",
+        "lastModified": 1649151322,
+        "narHash": "sha256-CwTpGx2Vx/m3bMbeWMculOSsvGmg+OD/hd69dxBwU48=",
         "owner": "m-labs",
         "repo": "sipyco",
-        "rev": "1a9a3062451f5c5b125b006d1b9bee997f986abd",
+        "rev": "4a4a04988206db8821c3c8fa33dca478c738677c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "m-labs",
+        "repo": "sipyco",
+        "type": "github"
+      }
+    },
+    "sipyco_2": {
+      "inputs": {
+        "nixpkgs": "nixpkgs_4"
+      },
+      "locked": {
+        "lastModified": 1649151322,
+        "narHash": "sha256-CwTpGx2Vx/m3bMbeWMculOSsvGmg+OD/hd69dxBwU48=",
+        "owner": "m-labs",
+        "repo": "sipyco",
+        "rev": "4a4a04988206db8821c3c8fa33dca478c738677c",
         "type": "github"
       },
       "original": {
@@ -160,11 +217,11 @@
     "src-misoc": {
       "flake": false,
       "locked": {
-        "lastModified": 1641889368,
-        "narHash": "sha256-0Ai25lry9ju1HxFmfMRNKG8mamBqvw+kvDfpuK8Dtjo=",
+        "lastModified": 1649324486,
+        "narHash": "sha256-Mw/fQS3lHFvCm7L1k63joRkz5uyijQfywcOq+X2+o2s=",
         "ref": "master",
-        "rev": "7242dc5a41732135425acc4871487461dfae6c66",
-        "revCount": 2419,
+        "rev": "f1dc58d2b8c222ba41c25cee4301626625f46e43",
+        "revCount": 2420,
         "submodules": true,
         "type": "git",
         "url": "https://github.com/m-labs/misoc.git"