diff --git a/pkgs/applications/networking/davmail/default.nix b/pkgs/applications/networking/davmail/default.nix
index 9a49603f61da..9f19363d74fd 100644
--- a/pkgs/applications/networking/davmail/default.nix
+++ b/pkgs/applications/networking/davmail/default.nix
@@ -1,6 +1,6 @@
 {
   stdenv,
-  fetchurl,
+  fetchzip,
   lib,
   makeWrapper,
   unzip,
@@ -25,17 +25,16 @@ stdenv.mkDerivation rec {
   pname = "davmail";
   version = "6.3.0";
 
-  src = fetchurl {
+  src = fetchzip {
     url = "mirror://sourceforge/${pname}/${version}/${pname}-${version}-${toString rev}.zip";
-    hash = "sha256-Yh61ZHsEMF6SchLEyBV3rRI7pJ/bvR2K4G8U6jrPa3A=";
+    hash = "sha256-zJMwCFX/uJnLeThj6/t2usBRM+LIuamZt0EFLG3N+8k=";
+    stripRoot = false;
   };
 
   postPatch = ''
     sed -i -e '/^JAVA_OPTS/d' davmail
   '';
 
-  sourceRoot = ".";
-
   nativeBuildInputs = [
     makeWrapper
     unzip
diff --git a/pkgs/by-name/ge/geoserver/package.nix b/pkgs/by-name/ge/geoserver/package.nix
index 0cac26e6a027..0cee73f25f50 100644
--- a/pkgs/by-name/ge/geoserver/package.nix
+++ b/pkgs/by-name/ge/geoserver/package.nix
@@ -17,12 +17,19 @@ stdenv.mkDerivation (finalAttrs: rec {
     hash = "sha256-bhL+u+BoKgW2cwOXEzaq0h07dKFz9u9WB2jW8nAF0vI=";
   };
 
+  sourceRoot = "source";
+
+  unpackPhase = ''
+    runHook preUnpack
+    unzip $src -d "$sourceRoot"
+    runHook postUnpack
+  '';
+
   patches = [
     # set GEOSERVER_DATA_DIR to current working directory if not provided
     ./data-dir.patch
   ];
 
-  sourceRoot = ".";
   nativeBuildInputs = [
     unzip
     makeWrapper
diff --git a/pkgs/by-name/po/powershell/package.nix b/pkgs/by-name/po/powershell/package.nix
index 6845d30445ec..258528daa8c3 100644
--- a/pkgs/by-name/po/powershell/package.nix
+++ b/pkgs/by-name/po/powershell/package.nix
@@ -38,7 +38,14 @@ stdenv.mkDerivation rec {
     passthru.sources.${stdenv.hostPlatform.system}
       or (throw "Unsupported system: ${stdenv.hostPlatform.system}");
 
-  sourceRoot = ".";
+  sourceRoot = "source";
+
+  unpackPhase = ''
+    runHook preUnpack
+    mkdir -p "$sourceRoot"
+    tar xf $src --directory="$sourceRoot"
+    runHook postUnpack
+  '';
 
   strictDeps = true;
 
diff --git a/pkgs/by-name/un/unihan-database/package.nix b/pkgs/by-name/un/unihan-database/package.nix
index 1cabda4b99dd..e3b2d493c644 100644
--- a/pkgs/by-name/un/unihan-database/package.nix
+++ b/pkgs/by-name/un/unihan-database/package.nix
@@ -18,7 +18,13 @@ stdenv.mkDerivation rec {
     unzip
   ];
 
-  sourceRoot = ".";
+  sourceRoot = "source";
+
+  unpackPhase = ''
+    runHook preUnpack
+    unzip $src -d $sourceRoot
+    runHook postUnpack
+  '';
 
   installPhase = ''
     runHook preInstall
diff --git a/pkgs/by-name/xm/xmage/package.nix b/pkgs/by-name/xm/xmage/package.nix
index 2fb74e7215a9..5dfb04c6b195 100644
--- a/pkgs/by-name/xm/xmage/package.nix
+++ b/pkgs/by-name/xm/xmage/package.nix
@@ -17,8 +17,14 @@ stdenv.mkDerivation (finalAttrs: {
 
   preferLocalBuild = true;
 
+  nativeBuildInputs = [ unzrip ];
+
+  sourceRoot = "source";
+
   unpackPhase = ''
-    ${unzrip}/bin/unzrip $src
+    runHook preUnpack
+    unzrip $src -d "$sourceRoot"
+    runHook postUnpack
   '';
 
   installPhase =
diff --git a/pkgs/servers/ombi/default.nix b/pkgs/servers/ombi/default.nix
index c537a3de6907..35097500bf0a 100644
--- a/pkgs/servers/ombi/default.nix
+++ b/pkgs/servers/ombi/default.nix
@@ -35,13 +35,20 @@ stdenv.mkDerivation rec {
   pname = "ombi";
   version = "4.47.1";
 
-  sourceRoot = ".";
-
   src = fetchurl {
     url = "https://github.com/Ombi-app/Ombi/releases/download/v${version}/${os}-${arch}.tar.gz";
     sha256 = hash;
   };
 
+  sourceRoot = "source";
+
+  unpackPhase = ''
+    runHook preUnpack
+    mkdir -p "$sourceRoot"
+    tar xf $src --directory="$sourceRoot"
+    runHook postUnpack
+  '';
+
   nativeBuildInputs =
     [ makeWrapper ]
     ++ lib.optional stdenv.hostPlatform.isLinux autoPatchelfHook
diff --git a/pkgs/top-level/dotnet-packages.nix b/pkgs/top-level/dotnet-packages.nix
index 1ba6d4a24785..37a7a298b088 100644
--- a/pkgs/top-level/dotnet-packages.nix
+++ b/pkgs/top-level/dotnet-packages.nix
@@ -175,6 +175,7 @@ let
       version = "11.0.2";
       sha256 = "07na27n4mlw77f3hg5jpayzxll7f4gyna6x7k9cybmxpbs6l77k7";
       outputFiles = [ "*" ];
+      postInstall = "rm $target/env-vars"; # fetchNuGet already sets preInstall
     };
 
     Paket = fetchNuGet {
@@ -182,6 +183,7 @@ let
       version = "5.179.1";
       sha256 = "11rzna03i145qj08hwrynya548fwk8xzxmg65swyaf19jd7gzg82";
       outputFiles = [ "*" ];
+      postInstall = "rm $target/env-vars"; # fetchNuGet already sets preInstall
     };
 
   };