diff --git a/hacking/nix/scope/microkit/default.nix b/hacking/nix/scope/microkit/default.nix
index cc8a45c4d..e0db26f8a 100644
--- a/hacking/nix/scope/microkit/default.nix
+++ b/hacking/nix/scope/microkit/default.nix
@@ -68,6 +68,13 @@ let
     dontConfigure = true;
     dontFixup = true;
 
+    # TODO make PR upstream to improve flexibility
+    postPatch = ''
+      substituteInPlace build_sdk.py --replace \
+        '"riscv64-unknown-elf-"' \
+        '"${stdenv.cc.targetPrefix}"'
+    '';
+
     buildPhase = ''
       python3 build_sdk.py \
         --sel4=${kernelSourcePatched} \
diff --git a/hacking/nix/scope/sources.nix b/hacking/nix/scope/sources.nix
index ea2f2c973..65bb39962 100644
--- a/hacking/nix/scope/sources.nix
+++ b/hacking/nix/scope/sources.nix
@@ -62,7 +62,7 @@ in rec {
 
   microkit = fetchGit {
     url = "https://github.com/coliasgroup/microkit.git";
-    rev = "9633b9cf9a29b227512762f3102c7868bae4b840"; # branch "rust-nix"
+    rev = "2492fa64b2e4930e5f3beb77be8914e5f35a2746"; # branch "rust-nix"
     local = localRoot + "/microkit";
   };
 
diff --git a/hacking/nix/scope/world/instances/microkit/default.nix b/hacking/nix/scope/world/instances/microkit/default.nix
index 2311ff9a7..551e74312 100644
--- a/hacking/nix/scope/world/instances/microkit/default.nix
+++ b/hacking/nix/scope/world/instances/microkit/default.nix
@@ -4,7 +4,7 @@
 # SPDX-License-Identifier: BSD-2-Clause
 #
 
-{ lib, stdenv
+{ lib, stdenv, hostPlatform
 , buildPackages, pkgsBuildBuild
 , linkFarm, symlinkJoin, writeText, runCommand, runCommandCC
 , callPackage
@@ -62,7 +62,7 @@ in {
         }
     );
 
-    banscii = maybe isMicrokit (callPackage ./banscii {
+    banscii = maybe (isMicrokit && seL4Config.PLAT == "qemu-arm-virt") (callPackage ./banscii {
       inherit canSimulate;
       inherit mkPD;
     });
@@ -106,7 +106,7 @@ in {
         }
     );
 
-    reset = maybe isMicrokit (
+    reset = maybe (isMicrokit && hostPlatform.isAarch64) (
       let
         pd = rec {
           orig = mkPD rec {
diff --git a/hacking/nix/scope/worlds.nix b/hacking/nix/scope/worlds.nix
index b0da27149..bade0e7d0 100644
--- a/hacking/nix/scope/worlds.nix
+++ b/hacking/nix/scope/worlds.nix
@@ -269,13 +269,27 @@ in rec {
           mk =
             { mcs ? false
             , smp ? false
+            , mkLoaderQEMUArgs ? loader: [ "-kernel" loader ]
+
+            , debugBuild ? null
+
+            , isMicrokit ? false
+            , microkitBoard ? null
+            , microkitConfig ? if debugBuild == null || debugBuild then "debug" else "release"
+
+            , extraQEMUArgs ? []
             }:
             let
               numCores = if smp then "2" else "1";
-              qemuMemory = "3072";
+              qemuMemory = "2048";
             in
               mkWorld {
-                inherit kernelLoaderConfig microkitConfig;
+                inherit kernelLoaderConfig;
+                inherit isMicrokit;
+                microkitConfig = {
+                  board = microkitBoard;
+                  config = microkitConfig;
+                };
                 kernelConfig = kernelConfigCommon // {
                   QEMU_MEMORY = mkString qemuMemory;
                   KernelArch = mkString "riscv";
@@ -292,9 +306,8 @@ in rec {
                       "-cpu" "rv64" "-smp" numCores "-m" "size=${qemuMemory}"
                       "-nographic"
                       "-serial" "mon:stdio"
-                      "-kernel" loader
                       # "-d" "unimp,guest_errors"
-                  ];
+                  ] ++ mkLoaderQEMUArgs loader ++ extraQEMUArgs;
                 };
               };
         in rec {
@@ -307,6 +320,11 @@ in rec {
             smp = mk { mcs = false; smp = true; };
             nosmp = mk { mcs = false; smp = false; };
           };
+          microkit = mk {
+            mcs = true;
+            isMicrokit = true;
+            microkitBoard = "qemu_virt_riscv64";
+          };
         };
 
       spike = mkWorld {
diff --git a/hacking/nix/top-level/default.nix b/hacking/nix/top-level/default.nix
index 6947d5c6c..add3a9b18 100644
--- a/hacking/nix/top-level/default.nix
+++ b/hacking/nix/top-level/default.nix
@@ -19,6 +19,7 @@ in {
     pkgs.host.aarch64.none.this.worlds.qemu-arm-virt.microkit
     pkgs.host.aarch32.none.this.worlds.default
     pkgs.host.riscv64.default.none.this.worlds.default
+    pkgs.host.riscv64.default.none.this.worlds.qemu-riscv-virt.microkit
     pkgs.host.riscv32.default.none.this.worlds.default
     pkgs.host.x86_64.none.this.worlds.default
   ];