diff --git a/pkgs/applications/networking/flexget/default.nix b/pkgs/applications/networking/flexget/default.nix
index a469287ed4d0..8caef5528ba3 100644
--- a/pkgs/applications/networking/flexget/default.nix
+++ b/pkgs/applications/networking/flexget/default.nix
@@ -5,23 +5,20 @@
 
 python3Packages.buildPythonApplication rec {
   pname = "flexget";
-  version = "3.4.2";
+  version = "3.5.4";
+  format = "pyproject";
 
   # Fetch from GitHub in order to use `requirements.in`
   src = fetchFromGitHub {
     owner = "flexget";
     repo = "flexget";
     rev = "refs/tags/v${version}";
-    hash = "sha256-mq1xk27mIB1iiCphwMZRVqlIRwlYHihXSowQ9GAkR1U=";
+    hash = "sha256-KANnZLNNDEo8pVWumFRR/Y67F1eS2JeDeX33nQ5YWlk=";
   };
 
   postPatch = ''
-    # Symlink requirements.in because upstream uses `pip-compile` which yields
-    # python-version dependent requirements
-    ln -sf requirements.in requirements.txt
-
-    # remove dependency constraints
-    sed 's/[~<>=].*//' -i requirements.txt
+    # remove dependency constraints but keep environment constraints
+    sed 's/[~<>=][^;]*//' -i requirements.txt
 
     # "zxcvbn-python" was renamed to "zxcvbn", and we don't have the former in
     # nixpkgs. See: https://github.com/NixOS/nixpkgs/issues/62110
@@ -32,7 +29,7 @@ python3Packages.buildPythonApplication rec {
   doCheck = false;
 
   propagatedBuildInputs = with python3Packages; [
-    # See https://github.com/Flexget/Flexget/blob/master/requirements.in
+    # See https://github.com/Flexget/Flexget/blob/master/requirements.txt
     APScheduler
     beautifulsoup4
     click
@@ -55,6 +52,7 @@ python3Packages.buildPythonApplication rec {
     rich
     rpyc
     sqlalchemy
+    typing-extensions
 
     # WebUI requirements
     cherrypy