diff --git a/pkgs/by-name/no/nominatim-ui/package.nix b/pkgs/by-name/no/nominatim-ui/package.nix
index f4b09e84694b..323be48ae2cc 100644
--- a/pkgs/by-name/no/nominatim-ui/package.nix
+++ b/pkgs/by-name/no/nominatim-ui/package.nix
@@ -2,8 +2,31 @@
   lib,
   stdenv,
   fetchFromGitHub,
+  fetchYarnDeps,
+  writableTmpDirAsHomeHook,
+  writeText,
+
+  fixup-yarn-lock,
+  nodejs,
+  yarn,
+
+  # Custom application configuration placed to theme/config.theme.js file
+  # For the list of available configuration options see
+  # https://github.com/osm-search/nominatim-ui/blob/master/dist/config.defaults.js
+  customConfig ? null,
 }:
 
+let
+  configFile =
+    if customConfig != null then
+      writeText "config.theme.js" customConfig
+    else
+      writeText "config.theme.js" ''
+        // Default configuration
+        Nominatim_Config.Nominatim_API_Endpoint='https://127.0.0.1/';
+      '';
+in
+
 stdenv.mkDerivation (finalAttrs: {
   pname = "nominatim-ui";
   version = "3.7.1";
@@ -15,6 +38,43 @@ stdenv.mkDerivation (finalAttrs: {
     hash = "sha256-TliTWDKdIp7Z0uYw5P65i06NQAUNwNymUsSYrihVZFE=";
   };
 
+  offlineCache = fetchYarnDeps {
+    yarnLock = "${finalAttrs.src}/yarn.lock";
+    hash = "sha256-IqwsXEd9RSJhkA4BONTJT4xYMTyG9+zddIpD47v6AFc=";
+  };
+
+  nativeBuildInputs = [
+    writableTmpDirAsHomeHook
+
+    fixup-yarn-lock
+    nodejs
+    yarn
+  ];
+
+  configurePhase = ''
+    runHook preConfigure
+
+    yarn config --offline set yarn-offline-mirror $offlineCache
+    fixup-yarn-lock yarn.lock
+
+    yarn install --offline --frozen-lockfile --frozen-engines --ignore-scripts
+    patchShebangs node_modules
+
+    runHook postConfigure
+  '';
+
+  buildPhase = ''
+    runHook preBuild
+
+    yarn --offline build
+
+    runHook postBuild
+  '';
+
+  preInstall = ''
+    ln --symbolic ${configFile} dist/theme/config.theme.js
+  '';
+
   installPhase = ''
     runHook preInstall