diff --git a/src/kiri/conf.js b/src/kiri/conf.js
index 1db3bf90..6f9ea437 100644
--- a/src/kiri/conf.js
+++ b/src/kiri/conf.js
@@ -17,7 +17,7 @@
 
     // add fields to o(bject) from d(efault) that are missing
     // remove fields from o(bject) that don't exist in d(efault)
-    function fill_cull_once(obj, def) {
+    function fill_cull_once(obj, def, debug) {
         if (!obj) return;
         // handle renaming
         for (let k in obj) {
@@ -26,6 +26,7 @@
                 if (nam !== k) {
                     // handle field renames
                     obj[nam] = obj[k];
+                    if (debug) console.log({rename: k, to: nam});
                     delete obj[k];
                 }
             }
@@ -36,15 +37,19 @@
                 let okv = obj[k];
                 if ((okv === undefined || okv === null)) {
                     // handle fill
-                    // console.log({fill: k});
-                    obj[k] = def[k];
+                    if (debug) console.log({fill: k, val: def[k]});
+                    if (typeof def[k] === 'object') {
+                        obj[k] = clone(def[k]);
+                    } else {
+                        obj[k] = def[k];
+                    }
                 }
             }
         }
         // remove invalid
         for (let k in obj) {
             if (!def.hasOwnProperty(k)) {
-                // console.log({cull: k});
+                if (debug) console.log({cull: k});
                 delete obj[k];
             }
         }
@@ -119,6 +124,8 @@
             gcodeLayer: valueOf(cmd.layer || code.layer, []),
             gcodePre: valueOf(code.pre, []),
             gcodePost: valueOf(code.post, []),
+            gcodeExt: valueOf(code.ext, []),
+            gcodeInt: valueOf(code.int, []),
             // post processor script of which only one exists
             // for XYZ.daVinci.Mini.w triggered in kiri.export
             // in the fdm driver to turn gcode into base64
@@ -266,6 +273,8 @@
                     maxHeight: 150,
                     gcodePre: [],
                     gcodePost: [],
+                    gcodeExt: [],
+                    gcodeInt: [],
                     gcodePause: [],
                     gcodeProc: "",
                     gcodeFan: [],
diff --git a/src/kiri/init.js b/src/kiri/init.js
index 7e1f95c3..350aeb18 100644
--- a/src/kiri/init.js
+++ b/src/kiri/init.js
@@ -752,6 +752,8 @@
                 UI.deviceName,
                 UI.gcodePre,
                 UI.gcodePost,
+                UI.gcodeExt,
+                UI.gcodeInt,
                 UI.gcodePause,
                 UI.bedDepth,
                 UI.bedWidth,
@@ -1592,19 +1594,21 @@
             gcodeFExt:        UC.newInput(LANG.dv_fext_s, {title:LANG.dv_fext_l, modes:CAM_LASER, size:7, text:true}),
 
             gcodeEd:          UC.newGroup(LANG.dv_gr_gco, $('dg'), {group:"dgcp", inline:true, modes:GCODE}),
-            gcodeFanTrack: UC.newRow([
+            gcodeMacros:      UC.newRow([
                 (UI.gcodePre = UC.newGCode(LANG.dv_head_s, {title:LANG.dv_head_l, modes:GCODE, area:gcode})).button,
                 (UI.gcodePost = UC.newGCode(LANG.dv_foot_s, {title:LANG.dv_foot_l, modes:GCODE, area:gcode})).button,
                 (UI.gcodeFan = UC.newGCode(LANG.dv_fanp_s, {title:LANG.dv_fanp_l, modes:FDM, area:gcode})).button,
                 (UI.gcodeTrack = UC.newGCode(LANG.dv_prog_s, {title:LANG.dv_prog_l, modes:FDM, area:gcode})).button,
                 (UI.gcodeLayer = UC.newGCode(LANG.dv_layr_s, {title:LANG.dv_layr_l, modes:FDM, area:gcode})).button,
                 (UI.gcodePause = UC.newGCode(LANG.dv_paus_s, {title:LANG.dv_paus_l, modes:FDM, area:gcode})).button,
+                (UI.gcodeExt = UC.newGCode(LANG.dv_pext_s, {title:LANG.dv_pext_l, modes:FDM, area:gcode, show:isDanger})).button,
+                (UI.gcodeInt = UC.newGCode(LANG.dv_pint_s, {title:LANG.dv_pint_l, modes:FDM, area:gcode, show:isDanger})).button,
                 (UI.gcodeLaserOn = UC.newGCode(LANG.dv_lzon_s, {title:LANG.dv_lzon_l, modes:LASER, area:gcode})).button,
                 (UI.gcodeLaserOff = UC.newGCode(LANG.dv_lzof_s, {title:LANG.dv_lzof_l, modes:LASER, area:gcode})).button,
                 (UI.gcodeChange = UC.newGCode(LANG.dv_tool_s, {title:LANG.dv_tool_l, modes:CAM, area:gcode})).button,
                 (UI.gcodeDwell = UC.newGCode(LANG.dv_dwll_s, {title:LANG.dv_dwll_l, modes:CAM, area:gcode})).button,
                 (UI.gcodeSpindle = UC.newGCode(LANG.dv_sspd_s, {title:LANG.dv_sspd_l, modes:CAM, area:gcode})).button
-            ], {class:"ext-buttons f-row"}),
+            ], {class:"ext-buttons f-row gcode-macros"}),
 
             lprefs:           UC.newGroup(LANG.op_menu, $('prefs-gen1'), {inline: true}),
             reverseZoom:      UC.newBoolean(LANG.op_invr_s, booleanSave, {title:LANG.op_invr_l}),
diff --git a/src/kiri/main.js b/src/kiri/main.js
index f740973e..48522451 100644
--- a/src/kiri/main.js
+++ b/src/kiri/main.js
@@ -2126,14 +2126,17 @@
         // for each key in setrec object
         for (let key in setrec) {
             if (!setrec.hasOwnProperty(key)) {
+                // console.log({no_setrec: key});
                 continue;
             }
             if (!uirec.hasOwnProperty(key)) {
+                // console.log({no_uirec: key});
                 continue;
             }
             let nval = null, uie = uirec[key];
             // skip empty UI values
             if (!uie || uie === '') {
+                // console.log({uie_empty: key});
                 continue;
             }
             if (uie.type === 'text') {
@@ -2217,7 +2220,7 @@
         if (opt.controller) {
             return;
         }
-        updateSettingsFromFields(device);
+        updateSettingsFromFields(device, undefined, undefined, true);
         // range-specific values
         if (settings.mode === 'FDM' && viewMode === VIEWS.SLICE) {
             let changes = {};
diff --git a/src/kiri/print.js b/src/kiri/print.js
index b726331c..c2e200df 100644
--- a/src/kiri/print.js
+++ b/src/kiri/print.js
@@ -25,7 +25,8 @@
     let lastPoint = null,
         lastEmit = null,
         lastOut = null,
-        lastPos;
+        lastPos,
+        nextType;
 
     KIRI.Print = Print;
 
@@ -404,11 +405,16 @@
     /**
      * @constructor
      */
-    function Output(point, emit, speed, tool) {
+    function Output(point, emit, speed, tool, type) {
         this.point = point; // point to emit
         this.emit = emit; // emit (feed for printers, power for lasers, cut for cam)
         this.speed = speed;
         this.tool = tool;
+        this.type = type;
+    }
+
+    function setType(type) {
+        nextType = type;
     }
 
     /**
@@ -429,8 +435,9 @@
         // if (emit && emit < 1) console.log(emit);
         lastPoint = point;
         lastEmit = emit;
-        lastOut = new Output(point, emit, speed, tool);
+        lastOut = new Output(point, emit, speed, tool, nextType);
         array.push(lastOut);
+        nextType = undefined;
         return lastOut;
     }
 
@@ -1049,6 +1056,9 @@
                     }
                 }
 
+                // flag extrusion type as exterior
+                setType('ext');
+
                 // innermost shells
                 let inner = next.innerShells() || [];
 
@@ -1060,6 +1070,9 @@
                 // output outer polygons
                 if (shellOrder === -1) outputTraces(inner, { sort: shellOrder });
 
+                // flag extrusion type as interior
+                setType('int');
+
                 // output thin fill
                 outputFills(next.thin_fill, {near: true});
 
diff --git a/src/mode/fdm/export.js b/src/mode/fdm/export.js
index 7b347b37..39b71022 100644
--- a/src/mode/fdm/export.js
+++ b/src/mode/fdm/export.js
@@ -22,6 +22,8 @@
             gcodeFan = device.gcodeFan,
             gcodeLayer = device.gcodeLayer,
             gcodeTrack = device.gcodeTrack,
+            gcodeExt = device.gcodeExt,
+            gcodeInt = device.gcodeInt,
             tool = 0,
             fwRetract = device.fwRetract,
             isDanger = settings.controller.danger,
@@ -71,6 +73,7 @@
             nozzleTemp = process.firstLayerNozzleTemp || process.outputTemp,
             bedTemp = process.firstLayerBedTemp || process.outputBedTemp,
             fanSpeed = undefined,
+            lastType = undefined,
             lastNozzleTemp = nozzleTemp,
             lastBedTemp = bedTemp,
             lastFanSpeed = fanSpeed,
@@ -142,7 +145,6 @@
             });
         }
         for (let range of process.ranges) {
-            console.log({range});
             if (range.fields.outputLoops) {
                 rloops.push({
                     start: range.lo,
@@ -436,6 +438,19 @@
                 out = path[pidx];
                 speedMMM = (out.speed || process.outputFeedrate) * 60; // range
 
+                // emit gcode macro for changed print region
+                if (out.type !== last.type) {
+                    switch (out.type) {
+                        case 'ext':
+                            appendAllSub(gcodeExt);
+                            break;
+                        case 'int':
+                            appendAllSub(gcodeInt);
+                            break;
+                    }
+                    lastType = out.type;
+                }
+
                 // look for extruder change, run scripts, recalc emit factor
                 if (out.tool !== undefined && out.tool !== tool) {
                     appendAllSub(extruder.extDeselect);
diff --git a/web/kiri/lang/en.js b/web/kiri/lang/en.js
index b6ed3116..29325d44 100644
--- a/web/kiri/lang/en.js
+++ b/web/kiri/lang/en.js
@@ -131,6 +131,10 @@ kiri.lang['en-us'] = {
     dv_head_l:      "gcode header script",
     dv_foot_s:      "footer",
     dv_foot_l:      "gcode footer script",
+    dv_pext_s:      "exterior",
+    dv_pext_l:      ["gcode script run before","printing exterior lines"],
+    dv_pint_s:      "interior",
+    dv_pint_l:      ["gcode script run before","printing interior lines"],
     dv_lzon_s:      "laser on",
     dv_lzon_l:      "gcode laser on script",
     dv_lzof_s:      "laser off",