diff --git a/packages/font-glyphs/src/auto-build/composite.ptl b/packages/font-glyphs/src/auto-build/composite.ptl
index c5dc3bfe2..0b4a47c0c 100644
--- a/packages/font-glyphs/src/auto-build/composite.ptl
+++ b/packages/font-glyphs/src/auto-build/composite.ptl
@@ -76,19 +76,18 @@ glyph-block Autobuild-Enclosure-Shared : begin
 			local jobsOrig : if demandDecomposable decomposableJobs nonDecomposable
 			jobsOrig.push { origJobGlyphGn unicode parts :: restInfo }
 
-			if para.enableCvSs : begin
-				if demandDecomposable
-				: then : foreach part [items-of parts] : begin
-					local mesh : getGrMesh { part } AnyCvOrCherryPicking query-glyph
-					foreach {gr fromParts toParts} [items-of mesh] : foreach gn [items-of toParts]
-						decomposableRelGlyphs.add gn
-				: else : begin
-					local mesh : getGrMesh parts AnyCvOrCherryPicking query-glyph
-					foreach {gr fromParts toParts} [items-of mesh] : do
-						local fromGn : CircNameNoCheck unicode prefix fromParts suffix
-						local toGn   : CircName        unicode prefix toParts   suffix
-						nonDecomposable.push { toGn null toParts :: restInfo }
-						relApplications.push { gr fromGn toGn }
+			if demandDecomposable
+			: then : foreach part [items-of parts] : begin
+				local mesh : getGrMesh { part } AnyCvOrCherryPicking query-glyph
+				foreach {gr fromParts toParts} [items-of mesh] : foreach gn [items-of toParts]
+					decomposableRelGlyphs.add gn
+			: else : begin
+				local mesh : getGrMesh parts AnyCvOrCherryPicking query-glyph
+				foreach {gr fromParts toParts} [items-of mesh] : do
+					local fromGn : CircNameNoCheck unicode prefix fromParts suffix
+					local toGn   : CircName        unicode prefix toParts   suffix
+					nonDecomposable.push { toGn null toParts :: restInfo }
+					relApplications.push { gr fromGn toGn }
 
 		return : object nonDecomposable decomposableJobs decomposableRelGlyphs relApplications
 
diff --git a/packages/font-otl/src/gsub-cv-ss.ptl b/packages/font-otl/src/gsub-cv-ss.ptl
index 7e6da2ee3..2ed6f5666 100644
--- a/packages/font-otl/src/gsub-cv-ss.ptl
+++ b/packages/font-otl/src/gsub-cv-ss.ptl
@@ -58,19 +58,23 @@ class CvLookupManager
 		return lookup
 
 	public [linkDeps] : begin
-		if this.decompositionLookup : begin
+		if (this.decompositionLookup && this.altrenatesLookup) : begin
 			this.table.setDependency this.decompositionLookup this.altrenatesLookup
-		foreach lookupSS [items-of this.singleSubstLookups] : if lookupSS : begin
-			this.table.setDependency this.altrenatesLookup lookupSS
-		foreach lookupCP [items-of this.cherryPickingLookups] : if lookupCP : begin
-			this.table.setDependency lookupCP this.altrenatesLookup
+		if this.altrenatesLookup : begin
 			foreach lookupSS [items-of this.singleSubstLookups] : if lookupSS : begin
-				this.table.setDependency lookupCP lookupSS
+				this.table.setDependency this.altrenatesLookup lookupSS
+			foreach lookupCP [items-of this.cherryPickingLookups] : if lookupCP : begin
+				this.table.setDependency lookupCP this.altrenatesLookup
+				foreach lookupSS [items-of this.singleSubstLookups] : if lookupSS : begin
+					this.table.setDependency lookupCP lookupSS
 
 	public [linkCrossDeps other] : begin
-		this.table.setDependency this.altrenatesLookup other.altrenatesLookup
-		foreach lookupSS [items-of this.singleSubstLookups] : if lookupSS : begin
-			this.table.setDependency lookupSS other.altrenatesLookup
+		if (this.altrenatesLookup && other.altrenatesLookup) : begin
+			this.table.setDependency this.altrenatesLookup other.altrenatesLookup
+
+		if other.altrenatesLookup : begin
+			foreach lookupSS [items-of this.singleSubstLookups] : if lookupSS : begin
+				this.table.setDependency lookupSS other.altrenatesLookup
 
 	static [compare a b] : begin
 		if (a.tag < b.tag) : return (-1)
@@ -154,9 +158,10 @@ export : define [buildCVSS gsub para glyphStore] : begin
 		sortedCvs.sort CvLookupManager.compare
 
 		foreach cv [items-of sortedCvs] : begin
-			local st cv.altrenatesLookup.substitutions
-			foreach { k v } [pairs-of st] : foreach idx [range 0 v.length] : if [not v.(idx)]
-				set v.(idx) k
+			if cv.altrenatesLookup : begin
+				local st cv.altrenatesLookup.substitutions
+				foreach { k v } [pairs-of st] : foreach idx [range 0 v.length] : if [not v.(idx)]
+					set v.(idx) k
 			cv.linkDeps
 
 		for [local i 1] (i < sortedCvs.length) [inc i]
diff --git a/packages/font-otl/src/index.ptl b/packages/font-otl/src/index.ptl
index 097dd51a7..130440669 100644
--- a/packages/font-otl/src/index.ptl
+++ b/packages/font-otl/src/index.ptl
@@ -36,8 +36,7 @@ define [buildGSUB para glyphStore markGlyphs] : begin
 	# As it is a cv/ss "cherry picking".
 
 	# APLF
-	if para.enableCvSs : begin
-		buildGrFeature gsub glyphStore Gr.AplForm
+	buildGrFeature gsub glyphStore Gr.AplForm
 
 	# numr / dnom
 	buildGrFeature gsub glyphStore Gr.NumeratorForm
@@ -61,8 +60,7 @@ define [buildGSUB para glyphStore markGlyphs] : begin
 
 	# cv##, ss##
 	local cvs nothing
-	if para.enableCvSs : begin
-		set cvs : buildCVSS gsub para glyphStore
+	set cvs : buildCVSS gsub para glyphStore
 
 	# ccmp post cv/ss (for Ogonek shape transform)
 	buildCCMPPostCvSs gsub ccmp glyphStore markGlyphs
diff --git a/packages/glyph/src/block.mjs b/packages/glyph/src/block.mjs
index 1ca0f9217..53212c6c4 100644
--- a/packages/glyph/src/block.mjs
+++ b/packages/glyph/src/block.mjs
@@ -61,6 +61,26 @@ export class DependencyManager {
 		}
 		s.add(dependency);
 	}
+	hasGlyphToGlyphDependency(dependent, dependency) {
+		return this.hasGlyphToGlyphDependencyImpl(new Set(), dependent, dependency);
+	}
+
+	hasGlyphToGlyphDependencyImpl(alreadyScanned, dependent, dependency) {
+		// Prevent infinite recursion
+		if (alreadyScanned.has(dependent)) return true;
+		alreadyScanned.add(dependent);
+
+		// Check for direct dependency
+		if (!this.glyphToGlyph.has(dependent)) return false;
+		const ds = this.glyphToGlyph.get(dependent);
+		if (ds.has(dependency)) return true;
+
+		// Check for indirect dependency
+		for (const d of ds) {
+			if (this.hasGlyphToGlyphDependencyImpl(alreadyScanned, d, dependency)) return true;
+		}
+		return false;
+	}
 
 	traverseGlyphDependenciesImpl(glyphs, fBlockwiseExpand) {
 		let state = new Map();
diff --git a/packages/glyph/src/glyph.mjs b/packages/glyph/src/glyph.mjs
index 72e472855..c2d2b6e84 100644
--- a/packages/glyph/src/glyph.mjs
+++ b/packages/glyph/src/glyph.mjs
@@ -2,7 +2,7 @@ import * as util from "util";
 
 import * as Geom from "@iosevka/geometry";
 import { Anchor } from "@iosevka/geometry/anchor";
-import { Point, Vec2 } from "@iosevka/geometry/point";
+import { Vec2 } from "@iosevka/geometry/point";
 import { Transform } from "@iosevka/geometry/transform";
 
 export class Glyph {
@@ -66,6 +66,10 @@ export class Glyph {
 		if (!this._m_dependencyManager) return;
 		this._m_dependencyManager.addDependency(this, glyph);
 	}
+	hasDependency(other) {
+		if (!this._m_dependencyManager) return false;
+		return this._m_dependencyManager.hasGlyphToGlyphDependency(this, other);
+	}
 
 	// Copying
 	cloneFromGlyph(g) {
@@ -138,6 +142,7 @@ export class Glyph {
 	}
 	tryBecomeMirrorOf(dst, rankSet) {
 		if (rankSet.has(this) || rankSet.has(dst)) return;
+		if (dst.hasDependency(this)) return;
 		const csThis = this.geometry.unlinkReferences().toShapeStringOrNull();
 		const csDst = dst.geometry.unlinkReferences().toShapeStringOrNull();
 		if (csThis && csDst && csThis === csDst) {