diff --git a/solver/llbsolver/vertex.go b/solver/llbsolver/vertex.go
index c2f659c5788e..c5e3870a9d43 100644
--- a/solver/llbsolver/vertex.go
+++ b/solver/llbsolver/vertex.go
@@ -155,9 +155,8 @@ func (dpc *detectPrunedCacheID) Load(op *pb.Op, md *pb.OpMetadata, opt *solver.V
 }
 
 func Load(ctx context.Context, def *pb.Definition, polEngine SourcePolicyEvaluator, opts ...LoadOpt) (solver.Edge, error) {
-	return loadLLB(ctx, def, polEngine, func(dgst digest.Digest, pbOp *pb.Op, load func(digest.Digest) (solver.Vertex, error)) (solver.Vertex, error) {
-		opMetadata := def.Metadata[string(dgst)]
-		vtx, err := newVertex(dgst, pbOp, opMetadata, load, opts...)
+	return loadLLB(ctx, def, polEngine, func(dgst digest.Digest, op *op, load func(digest.Digest) (solver.Vertex, error)) (solver.Vertex, error) {
+		vtx, err := newVertex(dgst, op.Op, op.Metadata, load, opts...)
 		if err != nil {
 			return nil, err
 		}
@@ -198,7 +197,7 @@ func newVertex(dgst digest.Digest, op *pb.Op, opMeta *pb.OpMetadata, load func(d
 	return vtx, nil
 }
 
-func recomputeDigests(ctx context.Context, all map[digest.Digest]*pb.Op, visited map[digest.Digest]digest.Digest, dgst digest.Digest) (digest.Digest, error) {
+func recomputeDigests(ctx context.Context, all map[digest.Digest]*op, visited map[digest.Digest]digest.Digest, dgst digest.Digest) (digest.Digest, error) {
 	if dgst, ok := visited[dgst]; ok {
 		return dgst, nil
 	}
@@ -235,30 +234,38 @@ func recomputeDigests(ctx context.Context, all map[digest.Digest]*pb.Op, visited
 	return newDgst, nil
 }
 
+// op is a private wrapper around pb.Op that includes its metadata.
+type op struct {
+	*pb.Op
+	Metadata *pb.OpMetadata
+}
+
 // loadLLB loads LLB.
 // fn is executed sequentially.
-func loadLLB(ctx context.Context, def *pb.Definition, polEngine SourcePolicyEvaluator, fn func(digest.Digest, *pb.Op, func(digest.Digest) (solver.Vertex, error)) (solver.Vertex, error)) (solver.Edge, error) {
+func loadLLB(ctx context.Context, def *pb.Definition, polEngine SourcePolicyEvaluator, fn func(digest.Digest, *op, func(digest.Digest) (solver.Vertex, error)) (solver.Vertex, error)) (solver.Edge, error) {
 	if len(def.Def) == 0 {
 		return solver.Edge{}, errors.New("invalid empty definition")
 	}
 
-	allOps := make(map[digest.Digest]*pb.Op)
+	allOps := make(map[digest.Digest]*op)
 
 	var lastDgst digest.Digest
 
 	for _, dt := range def.Def {
-		var op pb.Op
-		if err := op.UnmarshalVT(dt); err != nil {
+		var pbop pb.Op
+		if err := pbop.Unmarshal(dt); err != nil {
 			return solver.Edge{}, errors.Wrap(err, "failed to parse llb proto op")
 		}
 		dgst := digest.FromBytes(dt)
 		if polEngine != nil {
-			if _, err := polEngine.Evaluate(ctx, op.GetSource()); err != nil {
+			if _, err := polEngine.Evaluate(ctx, pbop.GetSource()); err != nil {
 				return solver.Edge{}, errors.Wrap(err, "error evaluating the source policy")
 			}
 		}
-
-		allOps[dgst] = &op
+		allOps[dgst] = &op{
+			Op:       &pbop,
+			Metadata: def.Metadata[string(dgst)],
+		}
 		lastDgst = dgst
 	}
 
@@ -300,7 +307,7 @@ func loadLLB(ctx context.Context, def *pb.Definition, polEngine SourcePolicyEval
 			return nil, errors.Errorf("invalid missing input digest %s", dgst)
 		}
 
-		if err := opsutils.Validate(op); err != nil {
+		if err := opsutils.Validate(op.Op); err != nil {
 			return nil, err
 		}
 
diff --git a/solver/llbsolver/vertex_test.go b/solver/llbsolver/vertex_test.go
index 3123207221f2..7aa68c990f44 100644
--- a/solver/llbsolver/vertex_test.go
+++ b/solver/llbsolver/vertex_test.go
@@ -38,9 +38,9 @@ func TestRecomputeDigests(t *testing.T) {
 	require.NoError(t, err)
 	op2Digest := digest.FromBytes(op2Data)
 
-	all := map[digest.Digest]*pb.Op{
-		newDigest: op1,
-		op2Digest: op2,
+	all := map[digest.Digest]*op{
+		newDigest: {Op: op1},
+		op2Digest: {Op: op2},
 	}
 	visited := map[digest.Digest]digest.Digest{oldDigest: newDigest}
 
@@ -48,10 +48,10 @@ func TestRecomputeDigests(t *testing.T) {
 	require.NoError(t, err)
 	require.Len(t, visited, 2)
 	require.Len(t, all, 2)
-	assert.Equal(t, op1, all[newDigest])
+	assert.Equal(t, op1, all[newDigest].Op)
 	require.Equal(t, newDigest, visited[oldDigest])
-	require.Equal(t, op1, all[newDigest])
-	assert.Equal(t, op2, all[updated])
+	require.Equal(t, op1, all[newDigest].Op)
+	assert.Equal(t, op2, all[updated].Op)
 	require.Equal(t, newDigest, digest.Digest(op2.Inputs[0].Digest))
 	assert.NotEqual(t, op2Digest, updated)
 }
@@ -88,14 +88,14 @@ func TestIngestDigest(t *testing.T) {
 	// Read the definition from the test data and ensure it uses the
 	// canonical digests after recompute.
 	var lastDgst digest.Digest
-	all := map[digest.Digest]*pb.Op{}
+	all := map[digest.Digest]*op{}
 	for _, in := range def.Def {
-		op := new(pb.Op)
-		err := op.Unmarshal(in)
+		opNew := new(pb.Op)
+		err := opNew.Unmarshal(in)
 		require.NoError(t, err)
 
 		lastDgst = digest.FromBytes(in)
-		all[lastDgst] = op
+		all[lastDgst] = &op{Op: opNew}
 	}
 	fmt.Println(all, lastDgst)