diff --git a/glyphs/letters-unified-extended.ptl b/glyphs/letters-unified-extended.ptl
index d6b9b98..27b4942 100644
--- a/glyphs/letters-unified-extended.ptl
+++ b/glyphs/letters-unified-extended.ptl
@@ -118,25 +118,26 @@ export : define [apply] : begin
 		save 'gamma' 0x3B3
 
 
-	define [LambdaShape sw] : glyph-construction
+	define [LambdaShape sw _top] : glyph-construction
 		local TURN (CAP * 0.1)
 		local curviness 0.2
+		local top : fallback _top CAP
 		include : dispiro
 			widths.rhs sw
 			flat SB 0    [heading UPWARD]
 			curl SB TURN [heading UPWARD]
 			quadcontrols 0 curviness
-			g4   (MIDDLE - sw / 2) CAP [widths 0 (sw * 0.8)]
+			g4   (MIDDLE - sw / 2) top [widths 0 (sw * 0.8)]
 		include : dispiro
 			widths.lhs sw
 			flat RIGHTSB 0    [heading UPWARD]
 			curl RIGHTSB TURN [heading UPWARD]
 			quadcontrols 0 curviness
-			g4   (MIDDLE + sw / 2) CAP [widths (sw * 0.8) 0]
+			g4   (MIDDLE + sw / 2) top [widths (sw * 0.8) 0]
 
-		start-from (MIDDLE - sw / 2) CAP
-		line-to (MIDDLE + sw / 2) CAP
-		line-to MIDDLE (CAP - sw)
+		start-from (MIDDLE - sw / 2) top
+		line-to (MIDDLE + sw / 2) top
+		line-to MIDDLE (top - sw)
 
 		if SLAB : begin
 			include : CenterBottomSerif (SB + sw / 2 * HVCONTRAST) 0 JUT
@@ -153,7 +154,7 @@ export : define [apply] : begin
 
 	sketch # Delta
 		include glyphs.Lambda AS_BASE
-		include : HBar (SB + HALFSTROKE) (RIGHTSB - HALFSTROKE) HALFSTROKE
+		include : HBarBottom (SB + HALFSTROKE) (RIGHTSB - HALFSTROKE) 0
 		eject-contour 'serif'
 		save 'Delta' 0x394
 
diff --git a/glyphs/symbol-geometric.ptl b/glyphs/symbol-geometric.ptl
index 3fb9f90..732f720 100644
--- a/glyphs/symbol-geometric.ptl
+++ b/glyphs/symbol-geometric.ptl
@@ -340,7 +340,7 @@ export : define [apply] : begin
 	hollow 'smallwhitecircle' null 'smallblackcircle' [hollowScale : squareRadius * designParameters.geometric_small_x]
 	hollow 'hwsmallwhitecircle' null 'hwsmallblackcircle' [hollowScale (squareRadius * designParameters.geometric_small_x) 1]
 	hollow 'hwwhitecircle' null 'hwblackcircle'
-	hollow 'hwwhitediamond' null 'hwblackdiamond'
+	hollow 'hwwhitediamond' null 'hwblackdiamond' [hollowScale squareRadius nothing (hollowSW * [Math.sqrt 2])]
 	hollow 'whitediamond' 0x25C7 'blackdiamond' [hollowScale squareRadius nothing (hollowSW * [Math.sqrt 2])]
 
 	let [sts 0.75]
diff --git a/glyphs/symbol-math.ptl b/glyphs/symbol-math.ptl
index 5330be6..79e4bcd 100644
--- a/glyphs/symbol-math.ptl
+++ b/glyphs/symbol-math.ptl
@@ -438,7 +438,7 @@ export : define [apply] : begin
 			curl RIGHTSB  operBot
 		save 'aplbackslash'
 	
-	define aplBoxTfm : ScaleAround MIDDLE parenMid ((WIDTH - aplBoxSW * 1.75) / WIDTH)
+	define aplBoxTfm : ScaleAround MIDDLE parenMid [Math.min ((WIDTH - aplBoxSW * 1.75) / WIDTH) ((operTop - operBot) / (parenTop - parenBot))]
 
 	composite glyphs.equal aplBoxTfm glyphs.aplsquare [into-unicode 0x2338]
 	composite glyphs.divide aplBoxTfm glyphs.aplsquare [into-unicode 0x2339]
@@ -481,7 +481,14 @@ export : define [apply] : begin
 	composite glyphs.hwarrowdown glyphs.minus [into-unicode 0x2356]
 	composite glyphs.hwarrowdown aplBoxTfm glyphs.aplsquare [into-unicode 0x2357]
 	composite glyphs.singleQuote markset.plus glyphs.underlineBelow [into-unicode 0x2358]
-	composite glyphs.nabla glyphs.underlineBelow [into-unicode 0x2359]
+	composite
+		begin glyphs.space
+		LambdaShape OPERATORSTROKE (plusTop - plusBot + ACCENT)
+		HBarBottom (SB + OPERATORSTROKE / 2) (RIGHTSB - OPERATORSTROKE / 2) 0 OPERATORSTROKE
+		Realign MIDDLE ((plusTop - plusBot) / 2) MIDDLE parenMid
+		begin markset.plus
+		begin glyphs.underlineBelow
+		into-unicode 0x2359
 	composite glyphs.hwwhitediamond markset.plus glyphs.underlineBelow [into-unicode 0x235A]
 	composite glyphs.hwsmallwhitecircle markset.plus glyphs.underlineBelow [into-unicode 0x235B]
 	composite glyphs.hwwhitecircle markset.plus glyphs.underlineBelow [into-unicode 0x235C]