diff --git a/nixos/doc/manual/from_md/release-notes/rl-2111.section.xml b/nixos/doc/manual/from_md/release-notes/rl-2111.section.xml
index 7d046d39de75..b14ca9e3e72f 100644
--- a/nixos/doc/manual/from_md/release-notes/rl-2111.section.xml
+++ b/nixos/doc/manual/from_md/release-notes/rl-2111.section.xml
@@ -65,6 +65,13 @@
           be able to access programmers supported by flashrom.
         </para>
       </listitem>
+      <listitem>
+        <para>
+          <link xlink:href="https://vikunja.io">vikunja</link>, a to-do
+          list app. Available as
+          <link linkend="opt-services.vikunja.enable">services.vikunja</link>.
+        </para>
+      </listitem>
     </itemizedlist>
   </section>
   <section xml:id="sec-release-21.11-incompatibilities">
diff --git a/nixos/doc/manual/release-notes/rl-2111.section.md b/nixos/doc/manual/release-notes/rl-2111.section.md
index 96854ffdd745..8648f89dbd38 100644
--- a/nixos/doc/manual/release-notes/rl-2111.section.md
+++ b/nixos/doc/manual/release-notes/rl-2111.section.md
@@ -20,6 +20,8 @@ In addition to numerous new and upgraded packages, this release has the followin
 
 - Users of flashrom should migrate to [programs.flashrom.enable](options.html#opt-programs.flashrom.enable) and add themselves to the `flashrom` group to be able to access programmers supported by flashrom.
 
+- [vikunja](https://vikunja.io), a to-do list app. Available as [services.vikunja](#opt-services.vikunja.enable).
+
 ## Backward Incompatibilities {#sec-release-21.11-incompatibilities}
 
 - The `staticjinja` package has been upgraded from 1.0.4 to 3.0.1
diff --git a/nixos/modules/module-list.nix b/nixos/modules/module-list.nix
index 980e7027c98c..be640f53eb66 100644
--- a/nixos/modules/module-list.nix
+++ b/nixos/modules/module-list.nix
@@ -968,6 +968,7 @@
   ./services/web-apps/trilium.nix
   ./services/web-apps/selfoss.nix
   ./services/web-apps/shiori.nix
+  ./services/web-apps/vikunja.nix
   ./services/web-apps/virtlyst.nix
   ./services/web-apps/wiki-js.nix
   ./services/web-apps/whitebophir.nix
diff --git a/nixos/modules/services/web-apps/vikunja.nix b/nixos/modules/services/web-apps/vikunja.nix
new file mode 100644
index 000000000000..b0b6eb6df17e
--- /dev/null
+++ b/nixos/modules/services/web-apps/vikunja.nix
@@ -0,0 +1,145 @@
+{ pkgs, lib, config, ... }:
+
+with lib;
+
+let
+  cfg = config.services.vikunja;
+  format = pkgs.formats.yaml {};
+  configFile = format.generate "config.yaml" cfg.settings;
+  useMysql = cfg.database.type == "mysql";
+  usePostgresql = cfg.database.type == "postgres";
+in {
+  options.services.vikunja = with lib; {
+    enable = mkEnableOption "vikunja service";
+    package-api = mkOption {
+      default = pkgs.vikunja-api;
+      type = types.package;
+      defaultText = "pkgs.vikunja-api";
+      description = "vikunja-api derivation to use.";
+    };
+    package-frontend = mkOption {
+      default = pkgs.vikunja-frontend;
+      type = types.package;
+      defaultText = "pkgs.vikunja-frontend";
+      description = "vikunja-frontend derivation to use.";
+    };
+    environmentFiles = mkOption {
+      type = types.listOf types.path;
+      default = [ ];
+      description = ''
+        List of environment files set in the vikunja systemd service.
+        For example passwords should be set in one of these files.
+      '';
+    };
+    setupNginx = mkOption {
+      type = types.bool;
+      default = config.services.nginx.enable;
+      defaultText = "config.services.nginx.enable";
+      description = ''
+        Whether to setup NGINX.
+        Further nginx configuration can be done by changing
+        <option>services.nginx.virtualHosts.&lt;frontendHostname&gt;</option>.
+        This does not enable TLS or ACME by default. To enable this, set the
+        <option>services.nginx.virtualHosts.&lt;frontendHostname&gt;.enableACME</option> to
+        <literal>true</literal> and if appropriate do the same for
+        <option>services.nginx.virtualHosts.&lt;frontendHostname&gt;.forceSSL</option>.
+      '';
+    };
+    frontendScheme = mkOption {
+      type = types.enum [ "http" "https" ];
+      description = ''
+        Whether the site is available via http or https.
+        This does not configure https or ACME in nginx!
+      '';
+    };
+    frontendHostname = mkOption {
+      type = types.str;
+      description = "The Hostname under which the frontend is running.";
+    };
+
+    settings = mkOption {
+      type = format.type;
+      default = {};
+      description = ''
+        Vikunja configuration. Refer to
+        <link xlink:href="https://vikunja.io/docs/config-options/"/>
+        for details on supported values.
+        '';
+    };
+    database = {
+      type = mkOption {
+        type = types.enum [ "sqlite" "mysql" "postgres" ];
+        example = "postgres";
+        default = "sqlite";
+        description = "Database engine to use.";
+      };
+      host = mkOption {
+        type = types.str;
+        default = "localhost";
+        description = "Database host address. Can also be a socket.";
+      };
+      user = mkOption {
+        type = types.str;
+        default = "vikunja";
+        description = "Database user.";
+      };
+      database = mkOption {
+        type = types.str;
+        default = "vikunja";
+        description = "Database name.";
+      };
+      path = mkOption {
+        type = types.str;
+        default = "/var/lib/vikunja/vikunja.db";
+        description = "Path to the sqlite3 database file.";
+      };
+    };
+  };
+  config = lib.mkIf cfg.enable {
+    services.vikunja.settings = {
+      database = {
+        inherit (cfg.database) type host user database path;
+      };
+      service = {
+        frontendurl = "${cfg.frontendScheme}://${cfg.frontendHostname}/";
+      };
+      files = {
+        basepath = "/var/lib/vikunja/files";
+      };
+    };
+
+    systemd.services.vikunja-api = {
+      description = "vikunja-api";
+      after = [ "network.target" ] ++ lib.optional usePostgresql "postgresql.service" ++ lib.optional useMysql "mysql.service";
+      wantedBy = [ "multi-user.target" ];
+      path = [ cfg.package-api ];
+      restartTriggers = [ configFile ];
+
+      serviceConfig = {
+        Type = "simple";
+        DynamicUser = true;
+        StateDirectory = "vikunja";
+        ExecStart = "${cfg.package-api}/bin/vikunja";
+        Restart = "always";
+        EnvironmentFile = cfg.environmentFiles;
+      };
+    };
+
+    services.nginx.virtualHosts."${cfg.frontendHostname}" = mkIf cfg.setupNginx {
+      locations = {
+        "/" = {
+          root = cfg.package-frontend;
+          tryFiles = "try_files $uri $uri/ /";
+        };
+        "~* ^/(api|dav|\\.well-known)/" = {
+          proxyPass = "http://localhost:3456";
+          extraConfig = ''
+            client_max_body_size 20M;
+          '';
+        };
+      };
+    };
+
+    environment.etc."vikunja/config.yaml".source = configFile;
+  };
+}