diff --git a/CHANGELOG.md b/CHANGELOG.md
index 858f02b..d3bad10 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## vNext
 
+- Updating `poetry2nix` to fix build on `nixpkgs-unstable`
+  ([issues/40](https://github.com/vlaci/openconnect-sso/issues/40),
+  [pull/41](https://github.com/vlaci/openconnect-sso/pull/41))
+
 ## v0.6.2
 
 - Updating dependencies to newer versions
diff --git a/nix/sources.json b/nix/sources.json
index 0c0d8a0..9f2bfb9 100644
--- a/nix/sources.json
+++ b/nix/sources.json
@@ -5,22 +5,22 @@
         "homepage": "https://github.com/nmattia/niv",
         "owner": "nmattia",
         "repo": "niv",
-        "rev": "2ecfd86b631714b457e56d70dd83fa60435baeb6",
-        "sha256": "01j6727cws8blg1npp54b4w6xa0gpgyzhyws2vqgp8clnlnmqqhi",
+        "rev": "af958e8057f345ee1aca714c1247ef3ba1c15f5e",
+        "sha256": "1qjavxabbrsh73yck5dcq8jggvh3r2jkbr6b5nlz5d9yrqm9255n",
         "type": "tarball",
-        "url": "https://github.com/nmattia/niv/archive/2ecfd86b631714b457e56d70dd83fa60435baeb6.tar.gz",
+        "url": "https://github.com/nmattia/niv/archive/af958e8057f345ee1aca714c1247ef3ba1c15f5e.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "poetry2nix": {
-        "branch": "1.13.0",
+        "branch": "1.15.4",
         "description": "Convert poetry projects to nix automagically [maintainer=@adisbladis] ",
         "homepage": "",
         "owner": "nix-community",
         "repo": "poetry2nix",
-        "rev": "2acbe722a8846f6a2d11ca1f64d1ba46f62095c2",
-        "sha256": "1lqzlkn1wxfdq4dvc7b3113b2xj5pjdhnw7qf4540dvh8c01k8dg",
+        "rev": "66cb831032e66341d427f1d17699d1fbe4d1332e",
+        "sha256": "0b2m0ipwmg4x9pqsvwsaxska96m7nbl5cql7c2cc6l9ah22sglzz",
         "type": "tarball",
-        "url": "https://github.com/nix-community/poetry2nix/archive/2acbe722a8846f6a2d11ca1f64d1ba46f62095c2.tar.gz",
+        "url": "https://github.com/nix-community/poetry2nix/archive/66cb831032e66341d427f1d17699d1fbe4d1332e.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     }
 }