Fix logfeed build

packages/logfeed/logfeed.cabal

@@ -1,17 +1,13 @@
-cabal-version:      >=1.10
+cabal-version: >=1.10
 
 -- Initial package description 'logfeed.cabal' generated by 'cabal init'.
 -- For further documentation, see http://haskell.org/cabal/users-guide/
 
-name:               logfeed
-version:            0.1.0.0
-author:             maralorn
-maintainer:         mail@maralorn.de
-
--- copyright:
--- category:
-build-type:         Simple
-extra-source-files: CHANGELOG.md
+name:          logfeed
+version:       0.1.0.0
+author:        maralorn
+maintainer:    mail@maralorn.de
+build-type:    Simple
 
 executable log2rss
   main-is:            Main.hs
@@ -32,7 +28,7 @@ executable log2rss
     , text
     , time
 
-  default-language:   Haskell2010
+  default-language:   GHC2021
 
 executable mail2rss
   default-extensions: ImportQualifiedPost
@@ -58,4 +54,4 @@ executable mail2rss
     , text
     , time
 
-  default-language:   Haskell2010
+  default-language:   GHC2021

packages/logfeed/shell.nix

@@ -1,11 +0,0 @@
-{pkgs ? import (import ../../nix/sources.nix).nixos-unstable {}}: let
-  inherit (pkgs) haskellPackages;
-in
-  haskellPackages.shellFor {
-    withHoogle = true;
-    packages = p: [(import ./. {inherit pkgs;})];
-    buildInputs = builtins.attrValues {
-      inherit (haskellPackages) hlint cabal-install notmuch hsemail;
-      inherit (pkgs) coreutils zlib;
-    };
-  }