diff --git a/.github/workflows/update-nix-hashes.yml b/.github/workflows/update-nix-hashes.yml
index f9817fe1ea..6e937da527 100644
--- a/.github/workflows/update-nix-hashes.yml
+++ b/.github/workflows/update-nix-hashes.yml
@@ -10,129 +10,18 @@ on:
       - "bun.lock"
       - "package.json"
       - "packages/*/package.json"
+      - "flake.lock"
       - ".github/workflows/update-nix-hashes.yml"
   pull_request:
     paths:
       - "bun.lock"
       - "package.json"
       - "packages/*/package.json"
+      - "flake.lock"
       - ".github/workflows/update-nix-hashes.yml"
 
 jobs:
-  compute-node-modules-hash:
-    if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-          - system: x86_64-linux
-            host: blacksmith-4vcpu-ubuntu-2404
-          - system: aarch64-linux
-            host: blacksmith-4vcpu-ubuntu-2404-arm
-          - system: x86_64-darwin
-            host: macos-15-intel
-          - system: aarch64-darwin
-            host: macos-latest
-    runs-on: ${{ matrix.host }}
-    env:
-      SYSTEM: ${{ matrix.system }}
-
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@v6
-        with:
-          token: ${{ secrets.GITHUB_TOKEN }}
-          fetch-depth: 0
-          ref: ${{ github.head_ref || github.ref_name }}
-          repository: ${{ github.event.pull_request.head.repo.full_name || github.repository }}
-
-      - name: Setup Nix
-        uses: nixbuild/nix-quick-install-action@v34
-
-      - name: Compute node_modules hash
-        run: |
-          set -euo pipefail
-
-          DUMMY="sha256-AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA="
-          HASH_FILE="nix/hashes.json"
-          OUTPUT_FILE="hash-${SYSTEM}.txt"
-
-          export NIX_KEEP_OUTPUTS=1
-          export NIX_KEEP_DERIVATIONS=1
-
-          BUILD_LOG=$(mktemp)
-          TMP_JSON=$(mktemp)
-          trap 'rm -f "$BUILD_LOG" "$TMP_JSON"' EXIT
-
-          if [ ! -f "$HASH_FILE" ]; then
-            mkdir -p "$(dirname "$HASH_FILE")"
-            echo '{"nodeModules":{}}' > "$HASH_FILE"
-          fi
-
-          # Set dummy hash to force nix to rebuild and reveal correct hash
-          jq --arg system "$SYSTEM" --arg value "$DUMMY" \
-            '.nodeModules = (.nodeModules // {}) | .nodeModules[$system] = $value' "$HASH_FILE" > "$TMP_JSON"
-          mv "$TMP_JSON" "$HASH_FILE"
-
-          MODULES_ATTR=".#packages.${SYSTEM}.default.node_modules"
-          DRV_PATH="$(nix eval --raw "${MODULES_ATTR}.drvPath")"
-
-          echo "Building node_modules for ${SYSTEM} to discover correct hash..."
-          echo "Attempting to realize derivation: ${DRV_PATH}"
-          REALISE_OUT=$(nix-store --realise "$DRV_PATH" --keep-failed 2>&1 | tee "$BUILD_LOG" || true)
-
-          BUILD_PATH=$(echo "$REALISE_OUT" | grep "^/nix/store/" | head -n1 || true)
-          CORRECT_HASH=""
-
-          if [ -n "$BUILD_PATH" ] && [ -d "$BUILD_PATH" ]; then
-            echo "Realized node_modules output: $BUILD_PATH"
-            CORRECT_HASH=$(nix hash path --sri "$BUILD_PATH" 2>/dev/null || true)
-          fi
-
-          # Try to extract hash from build log
-          if [ -z "$CORRECT_HASH" ]; then
-            CORRECT_HASH="$(grep -E 'got:\s+sha256-[A-Za-z0-9+/=]+' "$BUILD_LOG" | awk '{print $2}' | head -n1 || true)"
-          fi
-
-          if [ -z "$CORRECT_HASH" ]; then
-            CORRECT_HASH="$(grep -A2 'hash mismatch' "$BUILD_LOG" | grep 'got:' | awk '{print $2}' | sed 's/sha256:/sha256-/' || true)"
-          fi
-
-          # Try to hash from kept failed build directory
-          if [ -z "$CORRECT_HASH" ]; then
-            KEPT_DIR=$(grep -oE "build directory.*'[^']+'" "$BUILD_LOG" | grep -oE "'/[^']+'" | tr -d "'" | head -n1 || true)
-            if [ -z "$KEPT_DIR" ]; then
-              KEPT_DIR=$(grep -oE '/nix/var/nix/builds/[^ ]+' "$BUILD_LOG" | head -n1 || true)
-            fi
-
-            if [ -n "$KEPT_DIR" ] && [ -d "$KEPT_DIR" ]; then
-              HASH_PATH="$KEPT_DIR"
-              [ -d "$KEPT_DIR/build" ] && HASH_PATH="$KEPT_DIR/build"
-
-              if [ -d "$HASH_PATH/node_modules" ]; then
-                CORRECT_HASH=$(nix hash path --sri "$HASH_PATH" 2>/dev/null || true)
-              fi
-            fi
-          fi
-
-          if [ -z "$CORRECT_HASH" ]; then
-            echo "Failed to determine correct node_modules hash for ${SYSTEM}."
-            cat "$BUILD_LOG"
-            exit 1
-          fi
-
-          echo "$CORRECT_HASH" > "$OUTPUT_FILE"
-          echo "Hash for ${SYSTEM}: $CORRECT_HASH"
-
-      - name: Upload hash artifact
-        uses: actions/upload-artifact@v6
-        with:
-          name: hash-${{ matrix.system }}
-          path: hash-${{ matrix.system }}.txt
-          retention-days: 1
-
-  commit-node-modules-hashes:
-    needs: compute-node-modules-hash
+  update-node-modules-hashes:
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository
     runs-on: blacksmith-4vcpu-ubuntu-2404
     env:
@@ -147,6 +36,9 @@ jobs:
           ref: ${{ github.head_ref || github.ref_name }}
           repository: ${{ github.event.pull_request.head.repo.full_name || github.repository }}
 
+      - name: Setup Nix
+        uses: nixbuild/nix-quick-install-action@v34
+
       - name: Configure git
         run: |
           git config --global user.email "action@github.com"
@@ -159,54 +51,47 @@ jobs:
           BRANCH="${TARGET_BRANCH:-${GITHUB_REF_NAME}}"
           git pull --rebase --autostash origin "$BRANCH"
 
-      - name: Download all hash artifacts
-        uses: actions/download-artifact@v7
-        with:
-          pattern: hash-*
-          merge-multiple: true
-
-      - name: Merge hashes into hashes.json
+      - name: Compute all node_modules hashes
         run: |
           set -euo pipefail
 
           HASH_FILE="nix/hashes.json"
+          SYSTEMS="x86_64-linux aarch64-linux x86_64-darwin aarch64-darwin"
 
           if [ ! -f "$HASH_FILE" ]; then
             mkdir -p "$(dirname "$HASH_FILE")"
             echo '{"nodeModules":{}}' > "$HASH_FILE"
           fi
 
-          echo "Merging hashes into ${HASH_FILE}..."
+          for SYSTEM in $SYSTEMS; do
+            echo "Computing hash for ${SYSTEM}..."
+            BUILD_LOG=$(mktemp)
+            trap 'rm -f "$BUILD_LOG"' EXIT
 
-          shopt -s nullglob
-          files=(hash-*.txt)
-          if [ ${#files[@]} -eq 0 ]; then
-            echo "No hash files found, nothing to update"
-            exit 0
-          fi
+            # The updater derivations use fakeHash, so they will fail and reveal the correct hash
+            UPDATER_ATTR=".#packages.x86_64-linux.${SYSTEM}_node_modules"
 
-          EXPECTED_SYSTEMS="x86_64-linux aarch64-linux x86_64-darwin aarch64-darwin"
-          for sys in $EXPECTED_SYSTEMS; do
-            if [ ! -f "hash-${sys}.txt" ]; then
-              echo "WARNING: Missing hash file for $sys"
+            nix build "$UPDATER_ATTR" --no-link 2>&1 | tee "$BUILD_LOG" || true
+
+            CORRECT_HASH="$(grep -E 'got:\s+sha256-[A-Za-z0-9+/=]+' "$BUILD_LOG" | awk '{print $2}' | head -n1 || true)"
+
+            if [ -z "$CORRECT_HASH" ]; then
+              CORRECT_HASH="$(grep -A2 'hash mismatch' "$BUILD_LOG" | grep 'got:' | awk '{print $2}' | sed 's/sha256:/sha256-/' || true)"
             fi
-          done
 
-          for f in "${files[@]}"; do
-            system="${f#hash-}"
-            system="${system%.txt}"
-            hash=$(cat "$f")
-            if [ -z "$hash" ]; then
-              echo "WARNING: Empty hash for $system, skipping"
-              continue
+            if [ -z "$CORRECT_HASH" ]; then
+              echo "Failed to determine correct node_modules hash for ${SYSTEM}."
+              cat "$BUILD_LOG"
+              exit 1
             fi
-            echo "  $system: $hash"
-            jq --arg sys "$system" --arg h "$hash" \
-              '.nodeModules = (.nodeModules // {}) | .nodeModules[$sys] = $h' "$HASH_FILE" > "${HASH_FILE}.tmp"
+
+            echo "  ${SYSTEM}: ${CORRECT_HASH}"
+            jq --arg sys "$SYSTEM" --arg h "$CORRECT_HASH" \
+              '.nodeModules[$sys] = $h' "$HASH_FILE" > "${HASH_FILE}.tmp"
             mv "${HASH_FILE}.tmp" "$HASH_FILE"
           done
 
-          echo "All hashes merged:"
+          echo "All hashes computed:"
           cat "$HASH_FILE"
 
       - name: Commit ${{ env.TITLE }} changes
diff --git a/flake.nix b/flake.nix
index 20833fc49e..0f42509374 100644
--- a/flake.nix
+++ b/flake.nix
@@ -33,17 +33,37 @@
       packages = forEachSystem (
         pkgs:
         let
-          opencode = pkgs.callPackage ./nix/opencode.nix {
+          node_modules = pkgs.callPackage ./nix/node_modules.nix {
             inherit rev;
           };
+          opencode = pkgs.callPackage ./nix/opencode.nix {
+            inherit node_modules;
+          };
           desktop = pkgs.callPackage ./nix/desktop.nix {
             inherit opencode;
           };
+          # nixpkgs cpu naming to bun cpu naming
+          cpuMap = { x86_64 = "x64"; aarch64 = "arm64"; };
+          # matrix of node_modules builds - these will always fail due to fakeHash usage
+          # but allow computation of the correct hash from any build machine for any cpu/os
+          # see the update-nix-hashes workflow for usage
+          moduleUpdaters = pkgs.lib.listToAttrs (
+            pkgs.lib.concatMap (cpu:
+              map (os: {
+                name = "${cpu}_${os}_node_modules";
+                value = node_modules.override {
+                  bunCpu = cpuMap.${cpu};
+                  bunOs = os;
+                  hash = pkgs.lib.fakeHash;
+                };
+              }) [ "linux" "darwin" ]
+            ) [ "x86_64" "aarch64" ]
+          );
         in
         {
           default = opencode;
           inherit opencode desktop;
-        }
+        } // moduleUpdaters
       );
     };
 }
diff --git a/nix/node_modules.nix b/nix/node_modules.nix
new file mode 100644
index 0000000000..981a60ef9b
--- /dev/null
+++ b/nix/node_modules.nix
@@ -0,0 +1,85 @@
+{
+  lib,
+  stdenvNoCC,
+  bun,
+  bunCpu ? if stdenvNoCC.hostPlatform.isAarch64 then "arm64" else "x64",
+  bunOs ? if stdenvNoCC.hostPlatform.isLinux then "linux" else "darwin",
+  rev ? "dirty",
+  hash ?
+    (lib.pipe ./hashes.json [
+      builtins.readFile
+      builtins.fromJSON
+    ]).nodeModules.${stdenvNoCC.hostPlatform.system},
+}:
+let
+  packageJson = lib.pipe ../packages/opencode/package.json [
+    builtins.readFile
+    builtins.fromJSON
+  ];
+in
+stdenvNoCC.mkDerivation {
+  pname = "opencode-node_modules";
+  version = "${packageJson.version}-${rev}";
+
+  src = lib.fileset.toSource {
+    root = ../.;
+    fileset = lib.fileset.intersection (lib.fileset.fromSource (lib.sources.cleanSource ../.)) (
+      lib.fileset.unions [
+        ../packages
+        ../bun.lock
+        ../package.json
+        ../patches
+        ../install
+      ]
+    );
+  };
+
+  impureEnvVars = lib.fetchers.proxyImpureEnvVars ++ [
+    "GIT_PROXY_COMMAND"
+    "SOCKS_SERVER"
+  ];
+
+  nativeBuildInputs = [
+    bun
+  ];
+
+  dontConfigure = true;
+
+  buildPhase = ''
+    runHook preBuild
+    export HOME=$(mktemp -d)
+    export BUN_INSTALL_CACHE_DIR=$(mktemp -d)
+    bun install \
+      --cpu="${bunCpu}" \
+      --os="${bunOs}" \
+      --frozen-lockfile \
+      --ignore-scripts \
+      --no-progress \
+      --linker=isolated
+    bun --bun ${./scripts/canonicalize-node-modules.ts}
+    bun --bun ${./scripts/normalize-bun-binaries.ts}
+    runHook postBuild
+  '';
+
+  installPhase = ''
+    runHook preInstall
+
+    mkdir -p $out
+    find . -type d -name node_modules -exec cp -R --parents {} $out \;
+
+    runHook postInstall
+  '';
+
+  dontFixup = true;
+
+  outputHashAlgo = "sha256";
+  outputHashMode = "recursive";
+  outputHash = hash;
+
+  meta.platforms = [
+    "aarch64-linux"
+    "x86_64-linux"
+    "aarch64-darwin"
+    "x86_64-darwin"
+  ];
+}
diff --git a/nix/opencode.nix b/nix/opencode.nix
index 4d6f8e9b42..23d9fbe34e 100644
--- a/nix/opencode.nix
+++ b/nix/opencode.nix
@@ -1,6 +1,7 @@
 {
   lib,
   stdenvNoCC,
+  callPackage,
   bun,
   sysctl,
   makeBinaryWrapper,
@@ -9,81 +10,12 @@
   installShellFiles,
   versionCheckHook,
   writableTmpDirAsHomeHook,
-  rev ? "dirty",
+  node_modules ? callPackage ./node-modules.nix { },
 }:
-let
-  packageJson = lib.pipe ../packages/opencode/package.json [
-    builtins.readFile
-    builtins.fromJSON
-  ];
-in
 stdenvNoCC.mkDerivation (finalAttrs: {
   pname = "opencode";
-  version = "${packageJson.version}-${rev}";
-
-  src = lib.fileset.toSource {
-    root = ../.;
-    fileset = lib.fileset.intersection (lib.fileset.fromSource (lib.sources.cleanSource ../.)) (
-      lib.fileset.unions [
-        ../packages
-        ../bun.lock
-        ../package.json
-        ../patches
-        ../install
-      ]
-    );
-  };
-
-  node_modules = stdenvNoCC.mkDerivation {
-    pname = "${finalAttrs.pname}-node_modules";
-    inherit (finalAttrs) version src;
-
-    impureEnvVars = lib.fetchers.proxyImpureEnvVars ++ [
-      "GIT_PROXY_COMMAND"
-      "SOCKS_SERVER"
-    ];
-
-    nativeBuildInputs = [
-      bun
-    ];
-
-    dontConfigure = true;
-
-    buildPhase = ''
-      runHook preBuild
-      export HOME=$(mktemp -d)
-      export BUN_INSTALL_CACHE_DIR=$(mktemp -d)
-      bun install \
-        --cpu="${if stdenvNoCC.hostPlatform.isAarch64 then "arm64" else "x64"}" \
-        --os="${if stdenvNoCC.hostPlatform.isLinux then "linux" else "darwin"}" \
-        --frozen-lockfile \
-        --ignore-scripts \
-        --no-progress \
-        --linker=isolated
-      bun --bun ${./scripts/canonicalize-node-modules.ts}
-      bun --bun ${./scripts/normalize-bun-binaries.ts}
-      runHook postBuild
-    '';
-
-    installPhase = ''
-      runHook preInstall
-
-      mkdir -p $out
-      find . -type d -name node_modules -exec cp -R --parents {} $out \;
-
-      runHook postInstall
-    '';
-
-    dontFixup = true;
-
-    outputHashAlgo = "sha256";
-    outputHashMode = "recursive";
-    outputHash =
-      (lib.pipe ./hashes.json [
-        builtins.readFile
-        builtins.fromJSON
-      ]).nodeModules.${stdenvNoCC.hostPlatform.system};
-  };
+  inherit (node_modules) version src;
+  inherit node_modules;
 
   nativeBuildInputs = [
     bun
@@ -159,11 +91,6 @@ stdenvNoCC.mkDerivation (finalAttrs: {
     homepage = "https://opencode.ai/";
     license = lib.licenses.mit;
     mainProgram = "opencode";
-    platforms = [
-      "aarch64-linux"
-      "x86_64-linux"
-      "aarch64-darwin"
-      "x86_64-darwin"
-    ];
+    inherit (node_modules.meta) platforms;
   };
 })