diff --git a/nixos/modules/module-list.nix b/nixos/modules/module-list.nix
index a9d20adc63fd..585cef9b42ec 100644
--- a/nixos/modules/module-list.nix
+++ b/nixos/modules/module-list.nix
@@ -886,6 +886,7 @@
   ./services/web-servers/meguca.nix
   ./services/web-servers/mighttpd2.nix
   ./services/web-servers/minio.nix
+  ./services/web-servers/molly-brown.nix
   ./services/web-servers/nginx/default.nix
   ./services/web-servers/nginx/gitweb.nix
   ./services/web-servers/phpfpm/default.nix
diff --git a/nixos/modules/services/web-servers/molly-brown.nix b/nixos/modules/services/web-servers/molly-brown.nix
new file mode 100644
index 000000000000..e9052a184b2d
--- /dev/null
+++ b/nixos/modules/services/web-servers/molly-brown.nix
@@ -0,0 +1,117 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.molly-brown;
+
+  settingsType = with types;
+    attrsOf (oneOf [
+      int
+      str
+      (listOf str)
+      (attrsOf (oneOf [ int str (listOf str) (attrsOf str) ]))
+    ]) // {
+      description = "primitive expression convertable to TOML";
+    };
+
+  configFile = pkgs.runCommand "molly-brown.toml" {
+    buildInputs = [ pkgs.remarshal ];
+    preferLocalBuild = true;
+    passAsFile = [ "settings" ];
+    settings = builtins.toJSON cfg.settings;
+  } "remarshal -if json -of toml < $settingsPath > $out";
+in {
+
+  options.services.molly-brown = {
+
+    enable = mkEnableOption "Molly-Brown Gemini server";
+
+    port = mkOption {
+      default = 1965;
+      type = types.port;
+      description = ''
+        TCP port for molly-brown to bind to.
+      '';
+    };
+
+    hostName = mkOption {
+      type = types.str;
+      example = literalExample "config.networking.hostName";
+      default = config.networking.hostName;
+      description = ''
+        The hostname to respond to requests for. Requests for URLs with
+        other hosts will result in a status 53 (PROXY REQUEST REFUSED)
+        response.
+      '';
+    };
+
+    certPath = mkOption {
+      type = types.path;
+      example = "/var/lib/acme/example.com/cert.pem";
+      description = ''
+        Path to TLS certificate. An ACME certificate and key may be
+        shared with an HTTP server, but only if molly-brown has
+        permissions allowing it to read such keys.
+
+        As an example:
+        <programlisting>
+        security.acme.certs."example.com".allowKeysForGroup = true;
+        systemd.services.molly-brown.serviceConfig.SupplementaryGroups =
+          [ config.security.acme.certs."example.com".group ];
+        </programlisting>
+      '';
+    };
+
+    keyPath = mkOption {
+      type = types.path;
+      example = "/var/lib/acme/example.com/key.pem";
+      description = "Path to TLS key. See <option>CertPath</option>.";
+    };
+
+    docBase = mkOption {
+      type = types.path;
+      example = "/var/lib/molly-brown";
+      description = "Base directory for Gemini content.";
+    };
+
+    settings = mkOption {
+      type = settingsType;
+      default = { };
+      description = ''
+        molly-brown configuration. Refer to
+        <link xlink:href="https://tildegit.org/solderpunk/molly-brown/src/branch/master/example.conf"/>
+        for details on supported values.
+      '';
+    };
+
+  };
+
+  config = mkIf cfg.enable {
+
+    services.molly-brown.settings = let logDir = "/var/log/molly-brown";
+    in {
+      Port = cfg.port;
+      Hostname = cfg.hostName;
+      CertPath = cfg.certPath;
+      KeyPath = cfg.keyPath;
+      DocBase = cfg.docBase;
+      AccessLog = "${logDir}/access.log";
+      ErrorLog = "${logDir}/error.log";
+    };
+
+    systemd.services.molly-brown = {
+      description = "Molly Brown gemini server";
+      after = [ "network.target" ];
+      wantedBy = [ "multi-user.target" ];
+      serviceConfig = {
+        DynamicUser = true;
+        LogsDirectory = "molly-brown";
+        ExecStart = "${pkgs.molly-brown}/bin/molly-brown -c ${configFile}";
+        Restart = "always";
+      };
+    };
+
+  };
+
+}
diff --git a/nixos/tests/molly-brown.nix b/nixos/tests/molly-brown.nix
new file mode 100644
index 000000000000..09ce42726ca9
--- /dev/null
+++ b/nixos/tests/molly-brown.nix
@@ -0,0 +1,71 @@
+import ./make-test-python.nix ({ pkgs, ... }:
+
+  let testString = "NixOS Gemini test successful";
+  in {
+
+    name = "molly-brown";
+    meta = with pkgs.stdenv.lib.maintainers; { maintainers = [ ehmry ]; };
+
+    nodes = {
+
+      geminiServer = { config, pkgs, ... }:
+        let
+          inherit (config.networking) hostName;
+          cfg = config.services.molly-brown;
+        in {
+
+          environment.systemPackages = [
+            (pkgs.writeScriptBin "test-gemini" ''
+              #!${pkgs.python3}/bin/python
+
+              import socket
+              import ssl
+              import tempfile
+              import textwrap
+              import urllib.parse
+
+              url = "gemini://geminiServer/init.gmi"
+              parsed_url = urllib.parse.urlparse(url)
+
+              s = socket.create_connection((parsed_url.netloc, 1965))
+              context = ssl.SSLContext()
+              context.check_hostname = False
+              context.verify_mode = ssl.CERT_NONE
+              s = context.wrap_socket(s, server_hostname=parsed_url.netloc)
+              s.sendall((url + "\r\n").encode("UTF-8"))
+              fp = s.makefile("rb")
+              print(fp.readline().strip())
+              print(fp.readline().strip())
+              print(fp.readline().strip())
+            '')
+          ];
+
+          networking.firewall.allowedTCPPorts = [ cfg.settings.Port ];
+
+          services.molly-brown = {
+            enable = true;
+            docBase = "/tmp/docs";
+            certPath = "/tmp/cert.pem";
+            keyPath = "/tmp/key.pem";
+          };
+
+          systemd.services.molly-brown.preStart = ''
+            ${pkgs.openssl}/bin/openssl genrsa -out "/tmp/key.pem"
+            ${pkgs.openssl}/bin/openssl req -new \
+              -subj "/CN=${config.networking.hostName}" \
+              -key "/tmp/key.pem" -out /tmp/request.pem
+            ${pkgs.openssl}/bin/openssl x509 -req -days 3650 \
+              -in /tmp/request.pem -signkey "/tmp/key.pem" -out "/tmp/cert.pem"
+
+            mkdir -p "${cfg.settings.DocBase}"
+            echo "${testString}" > "${cfg.settings.DocBase}/test.gmi"
+          '';
+        };
+    };
+    testScript = ''
+      geminiServer.wait_for_unit("molly-brown")
+      geminiServer.wait_for_open_port(1965)
+      geminiServer.succeed("test-gemini")
+    '';
+
+  })
diff --git a/pkgs/servers/gemini/molly-brown/default.nix b/pkgs/servers/gemini/molly-brown/default.nix
index eb5b85784dcd..216a4015ef95 100644
--- a/pkgs/servers/gemini/molly-brown/default.nix
+++ b/pkgs/servers/gemini/molly-brown/default.nix
@@ -1,4 +1,4 @@
-{ lib, buildGoPackage, fetchgit }:
+{ lib, buildGoPackage, fetchgit, nixosTests }:
 
 buildGoPackage rec {
   pname = "molly-brown";
@@ -15,6 +15,8 @@ buildGoPackage rec {
 
   goDeps = ./deps.nix;
 
+  passthru.tests.basic = nixosTests.molly-brown;
+
   meta = with lib; {
     description = "Full-featured Gemini server";
     homepage = "https://tildegit.org/solderpunk/molly-brown";