From 4c00d7762beb8e9a310e4f17697d0295b9467404 Mon Sep 17 00:00:00 2001
From: Reed Krantz <programming@krantz.one>
Date: Mon, 27 Apr 2026 19:03:26 -0500
Subject: [PATCH] feat(build123d): support multiple outputs from the builder
 script and replace the objectName and outputFileName with just outputName

---
 build123d/default.nix        | 58 +++++++++++++++++++++++++-----------
 build123d/template/flake.nix |  4 +--
 2 files changed, 43 insertions(+), 19 deletions(-)

diff --git a/build123d/default.nix b/build123d/default.nix
index 78a9890..6c9cdfc 100644
--- a/build123d/default.nix
+++ b/build123d/default.nix
@@ -33,25 +33,36 @@
             cadquery
             build123d
           ]);
+
+        outputExt = [
+          "step"
+          "stl"
+          "3mf"
+        ];
       in {
         options.krantz.build123d = {
-          enable = lib.mkEnableOption "executing a python build123d/cadquery file to get a 3d file";
-
-          objectName = lib.mkOption {
-            description = "What to name this object.";
-            type = lib.types.str;
-            example = "box";
-          };
+          enable = lib.mkEnableOption "executing a python build123d/cadquery file to generate 3d files";
 
           builder = lib.mkOption {
-            description = "The path to python cad script that generates the 3d file.";
+            description = "The path to python cad script that generates the 3d file(s).";
             type = lib.types.path;
             example = lib.literalExpression "./build3d.py";
           };
-          outputFileName = lib.mkOption {
-            description = "The name of the 3d file the builder script will output. After the builder is run this file must appear in the current working directory.";
+
+          outputName = lib.mkOption {
+            description = ''
+              The derivation's name that will also be used to rename the following default outputs.
+
+              ${
+                # output.${ext} where ext is from the outputExt list
+                lib.concatStringsSep "\n" (lib.map (ext: "* output.${ext}") outputExt)
+              }
+
+              If left empty no files will be renamed.
+            '';
             type = lib.types.str;
-            default = "output.step";
+            default = "";
+            example = "box_for_stuf";
           };
 
           devShell = {
@@ -83,7 +94,7 @@
               description = "The name of the attribute in packages to configure";
               type = lib.types.str;
               default = "default";
-              example = "step";
+              example = "3dfiles";
             };
           };
         };
@@ -106,18 +117,31 @@
 
           # Your custom packages
           # Accessible through 'nix build', 'nix shell', 'nix run', etc
-          packages.${cfg.package.name} = lib.mkIf cfg.package.enable (pkgs.runCommand cfg.objectName {}
+          packages.${cfg.package.name} = lib.mkIf cfg.package.enable (pkgs.runCommand cfg.outputName {}
             /*
             bash
             */
             ''
-              RESULT_FILE_NAME=${cfg.objectName}.${lib.last (lib.splitString "." cfg.outputFileName)}
+              mkdir $out
+              cd $out
 
               ${pyEnv}/bin/python ${cfg.builder}
 
-              mkdir $out
-              mv ${cfg.outputFileName} $out/$RESULT_FILE_NAME
-              ln -s ./$RESULT_FILE_NAME $out/${cfg.outputFileName}
+              ${
+                if cfg.outputName != ""
+                then
+                  /*
+                  bash
+                  */
+                  ''
+                    for ext in ${lib.concatStringsSep " " outputExt}; do
+                      if [[ -f output.$ext ]]; then
+                        mv output.$ext ${cfg.outputName}.$ext
+                      fi
+                    done
+                  ''
+                else ""
+              }
             '');
         };
       });
diff --git a/build123d/template/flake.nix b/build123d/template/flake.nix
index 3c474c9..4ad395d 100644
--- a/build123d/template/flake.nix
+++ b/build123d/template/flake.nix
@@ -28,9 +28,9 @@
       perSystem = {pkgs, ...}: {
         krantz.build123d = {
           enable = true;
-
-          objectName = "box";
           builder = ./build3d.py;
+
+          outputName = "box";
         };
       };
     };