diff --git a/pkgs/by-name/nixpkgs-bootstrap/master.nix b/pkgs/by-name/nixpkgs-bootstrap/master.nix
index 163228005..8676916f1 100644
--- a/pkgs/by-name/nixpkgs-bootstrap/master.nix
+++ b/pkgs/by-name/nixpkgs-bootstrap/master.nix
@@ -8,8 +8,8 @@
   mkNixpkgs ? import ./mkNixpkgs.nix {}
 }:
 mkNixpkgs {
-  rev = "edc63aabe4605bc459eabb95ff567b73e518ecd0";
-  sha256 = "sha256-M7xydS3m3a7KWlcptBjeymwB9S3M/FRIXgBT7Xbnf5c=";
-  version = "0-unstable-2025-01-19";
+  rev = "77c9ec1f655bf0fa92bf19d93ca24425a25830c6";
+  sha256 = "sha256-Gr9/B9nuNjaxLFmITlRH0Ua+G/Y/Kn8uKMmDiI5etrg=";
+  version = "0-unstable-2025-01-20";
   branch = "master";
 }
diff --git a/pkgs/by-name/nixpkgs-bootstrap/staging-next.nix b/pkgs/by-name/nixpkgs-bootstrap/staging-next.nix
index 8046d4608..0c51356e8 100644
--- a/pkgs/by-name/nixpkgs-bootstrap/staging-next.nix
+++ b/pkgs/by-name/nixpkgs-bootstrap/staging-next.nix
@@ -2,8 +2,8 @@
   mkNixpkgs ? import ./mkNixpkgs.nix {}
 }:
 mkNixpkgs {
-  rev = "0a5e75bb2ec4444475449ef0b4f1fa6a5ea64b58";
-  sha256 = "sha256-ZoU0fJrLIG5rgLrx3qRIgyv67SJ3r2nNRIBkYwKY28w=";
-  version = "0-unstable-2025-01-18";
+  rev = "cfed72e3bbb241d3824d9c58a85515a5714962cf";
+  sha256 = "sha256-FD4yHpv2BO9dPpzZLcNzyrqWC+3UbA8kb4p3EuLYAnQ=";
+  version = "0-unstable-2025-01-20";
   branch = "staging-next";
 }
diff --git a/pkgs/by-name/nixpkgs-bootstrap/staging.nix b/pkgs/by-name/nixpkgs-bootstrap/staging.nix
index 76caa2bdf..0f36c08ac 100644
--- a/pkgs/by-name/nixpkgs-bootstrap/staging.nix
+++ b/pkgs/by-name/nixpkgs-bootstrap/staging.nix
@@ -2,8 +2,8 @@
   mkNixpkgs ? import ./mkNixpkgs.nix {}
 }:
 mkNixpkgs {
-  rev = "cb92d2dad2f0881c58c05197a55299e6cc11d427";
-  sha256 = "sha256-T6hdIUwmJ2ND5pEEETOwSvWqQG+kesCbn27i9HOWX6I=";
-  version = "0-unstable-2025-01-19";
+  rev = "5ff390289e135e883d93ba6c5e03ef159fe1db2c";
+  sha256 = "sha256-CLsyTton1Z8hFRe3QPFKBIx+fwaLOzsQezFMcuBpkxg=";
+  version = "0-unstable-2025-01-20";
   branch = "staging";
 }
diff --git a/pkgs/linux-packages/imx258/package.nix b/pkgs/linux-packages/imx258/package.nix
index cf28da005..67503c8a0 100644
--- a/pkgs/linux-packages/imx258/package.nix
+++ b/pkgs/linux-packages/imx258/package.nix
@@ -20,7 +20,8 @@ stdenv.mkDerivation {
 
   makeFlags = [
     # "KERNELRELEASE=${kernel.modDirVersion}"
-    "KERNEL_DIR=${kernel.dev}/lib/modules/${kernel.modDirVersion}/build"
+    # "KERNEL_DIR=${kernel.dev}/lib/modules/${kernel.modDirVersion}/build"
+    "KERNEL_DIR=$(buildRoot)"
     "INSTALL_MOD_PATH=$(out)/lib/modules/${kernel.modDirVersion}/kernel"
     # from <repo:nixos/nixpkgs:pkgs/os-specific/linux/kernel/manual-config.nix>
     "O=$(buildRoot)"
@@ -32,6 +33,12 @@ stdenv.mkDerivation {
     "CROSS_COMPILE=${stdenv.cc.targetPrefix}"
   ];
 
+  preConfigure = ''
+    # starting with linux 6.13.0 it wants to write to `KERNEL_DIR`, so we copy that here to make it writable
+    cp -R ${kernel.dev}/lib/modules/${kernel.modDirVersion}/build .
+    export buildRoot=$(pwd)/build
+  '';
+
   # the modules shipped in-tree are .xz, so if i want to replace those i need to also xz this module:
   postInstall = ''
     find $out -name '*.ko' -exec xz {} \;
diff --git a/pkgs/linux-packages/rk818-charger/package.nix b/pkgs/linux-packages/rk818-charger/package.nix
index 01eecb80a..78644b9f9 100644
--- a/pkgs/linux-packages/rk818-charger/package.nix
+++ b/pkgs/linux-packages/rk818-charger/package.nix
@@ -30,7 +30,8 @@ stdenv.mkDerivation {
 
   makeFlags = [
     # "KERNELRELEASE=${kernel.modDirVersion}"
-    "KERNEL_DIR=${kernel.dev}/lib/modules/${kernel.modDirVersion}/build"
+    # "KERNEL_DIR=${kernel.dev}/lib/modules/${kernel.modDirVersion}/build"
+    "KERNEL_DIR=$(buildRoot)"
     "INSTALL_MOD_PATH=$(out)/lib/modules/${kernel.modDirVersion}/kernel"
     # from <repo:nixos/nixpkgs:pkgs/os-specific/linux/kernel/manual-config.nix>
     "O=$(buildRoot)"
@@ -38,10 +39,24 @@ stdenv.mkDerivation {
     "HOSTCC=${buildPackages.stdenv.cc}/bin/${buildPackages.stdenv.cc.targetPrefix}cc"
     "HOSTLD=${buildPackages.stdenv.cc.bintools}/bin/${buildPackages.stdenv.cc.targetPrefix}ld"
     "ARCH=${stdenv.hostPlatform.linuxArch}"
+    # other kernel flags:
+    # M
+    # KBUILD_EXTMOD
+    # KBUILD_OUTPUT
   ] ++ lib.optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
     "CROSS_COMPILE=${stdenv.cc.targetPrefix}"
   ];
 
+  preConfigure = ''
+    # starting with linux 6.13.0 it wants to write to `KERNEL_DIR`, so we copy that here to make it writable
+    cp -R ${kernel.dev}/lib/modules/${kernel.modDirVersion}/build .
+    export buildRoot=$(pwd)/build
+
+    chmod u+w -R build
+    # remove symbols associated with in-tree rk818 module to prevent `modpost` errors: we're intentionally overriding them
+    sed -i '/rk8xx_/d' ./build/Module.symvers
+  '';
+
   # the modules shipped in-tree are .xz, so if i want to replace those i need to also xz this module:
   postInstall = ''
     find $out -name '*.ko' -exec xz {} \;