yes

Signed-off-by: Slendi <slendi@socopon.com>

.gitignore

@@ -0,0 +1,2 @@
+.direnv
+

flake.nix

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+{
+  description = "My flake";
+
+  inputs = {
+    nixpkgs.url = "https://flakehub.com/f/NixOS/nixpkgs/0.1";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs =
+    {
+      self,
+      nixpkgs,
+      flake-utils,
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+      in
+      {
+        bundlers = rec {
+          proot-bundler =
+            drv:
+            pkgs.stdenvNoCC.mkDerivation {
+              name = "myApp.run";
+              nativeBuildInputs = [
+                pkgs.nix
+                pkgs.coreutils
+                pkgs.findutils
+                pkgs.gnutar
+                pkgs.gzip
+                pkgs.patchelf
+              ];
+              # patch proot as you described
+              prootPatched = pkgs.proot.overrideAttrs (_: {
+                postFixup = ''
+                  exe=$out/bin/proot
+                  ${pkgs.patchelf}/bin/patchelf \
+                    --set-interpreter ."$(${pkgs.patchelf}/bin/patchelf --print-interpreter $exe)" \
+                    --set-rpath "$(${pkgs.patchelf}/bin/patchelf --print-rpath $exe | sed 's|/nix/store/|./nix/store/|g')" \
+                    $exe
+                '';
+              });
+
+              buildCommand = ''
+                set -euo pipefail
+                # 1) Make payload dir that mirrors the bundle runtime layout
+                PAY="$PWD/payload"
+                mkdir -p "$PAY/nix/store"
+
+                # include app + patched proot in the payload closure
+                app=${drv}
+                proot=${
+                  self.bundlers.${system}.selfExtracting.prootPatched or ""
+                } # not callable; we want the attr above
+                proot=${
+                  pkgs.proot.overrideAttrs (_: {
+                    postFixup = "${pkgs.patchelf}/bin/patchelf --set-interpreter .\"$(${pkgs.patchelf}/bin/patchelf --print-interpreter $out/bin/proot)\" --set-rpath \"$( ${pkgs.patchelf}/bin/patchelf --print-rpath $out/bin/proot | sed 's|/nix/store/|./nix/store/|g')\" $out/bin/proot";
+                  })
+                }
+
+                # copy closure of app + proot into ./nix/store
+                paths=$( ${pkgs.nix}/bin/nix-store --query --requisites "$app" "$proot" )
+                for p in $paths; do
+                  cp -a --no-preserve=ownership "$p" "$PAY/nix/store/"
+                done
+
+                # discover targets for the launcher
+                APP_BIN=$(find "$app/bin" -maxdepth 1 -type f -perm -111 | head -n1)
+                APP_REL="/nix/store/$(basename "$(dirname "$APP_BIN")")/$(basename "$APP_BIN")"
+                PROOT_REL="/nix/store/$(basename "$proot")/bin/proot"
+
+                # 2) Tar.gz the payload
+                ( cd "$PAY" && tar -czf "$PWD/payload.tar.gz" . )
+
+                # 3) Assemble a self-extracting script at $out
+                cat > $out <<'SH'
+                #!/bin/sh
+                set -euf
+                # extract to temp dir
+                : "''${TMPDIR:=/tmp}"
+                EXTRACT_DIR="$(mktemp -d "''${TMPDIR%/}/nxbdl.XXXXXX")"
+                cleanup() { [ -n "''${KEEP_BUNDLE:-}" ] || rm -rf "$EXTRACT_DIR"; }
+                trap cleanup EXIT INT TERM
+
+                # locate embedded archive (line after marker)
+                ARCHIVE_LINE=$(awk '/^__ARCHIVE_BELOW__/ {print NR+1; exit 0}' "$0")
+                tail -n +$ARCHIVE_LINE "$0" | tar -xzf - -C "$EXTRACT_DIR"
+
+                cd "$EXTRACT_DIR"
+                # vars substituted by bundler at build time:
+                APP_REL='__APP_REL__'
+                PROOT_REL='__PROOT_REL__'
+
+                # run via proot
+                BUNDLE_PWD="''${BUNDLE_PWD:-$PWD}"
+                exec ".$PROOT_REL" \
+                  -b ./nix:nix \
+                  -R / \
+                  -w "$BUNDLE_PWD" \
+                  ".$APP_REL" "$@"
+
+                __ARCHIVE_BELOW__
+                SH
+
+                # substitute the program + proot paths into the stub
+                sed -i \
+                  -e "s|__APP_REL__|$APP_REL|g" \
+                  -e "s|__PROOT_REL__|$PROOT_REL|g" \
+                  $out
+                chmod +x $out
+
+                # 4) Append the payload bytes after the marker
+                cat payload.tar.gz >> $out
+              '';
+            };
+
+          default = proot-bundler;
+        };
+      }
+    );
+}