diff --git a/lang/ast/scopegraph.go b/lang/ast/scopegraph.go
new file mode 100644
index 00000000..374633f8
--- /dev/null
+++ b/lang/ast/scopegraph.go
@@ -0,0 +1,201 @@
+// Mgmt
+// Copyright (C) 2013-2023+ James Shubin and the project contributors
+// Written by James Shubin <james@shubin.ca> and the project contributors
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package ast
+
+import (
+	"fmt"
+
+	"github.com/purpleidea/mgmt/lang/interfaces"
+	"github.com/purpleidea/mgmt/pgraph"
+)
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *StmtBind) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *StmtRes) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+	name, ok := obj.Name.(interfaces.ScopeGrapher)
+	if !ok {
+		panic("can't graph scope") // programming error
+	}
+	name.ScopeGraph(g)
+	g.AddEdge(obj, obj.Name, &pgraph.SimpleEdge{Name: "name"})
+	for _, resContents := range obj.Contents {
+		switch r := resContents.(type) {
+		case *StmtResField:
+			rValue, ok := r.Value.(interfaces.ScopeGrapher)
+			if !ok {
+				panic("can't graph scope") // programming error
+			}
+			rValue.ScopeGraph(g)
+			g.AddEdge(obj, r.Value, &pgraph.SimpleEdge{Name: r.Field})
+		}
+	}
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *StmtEdge) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *StmtIf) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *StmtProg) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+	for _, stmt := range obj.Body {
+		stmt, ok := stmt.(interfaces.ScopeGrapher)
+		if !ok {
+			panic("can't graph scope") // programming error
+		}
+		stmt.ScopeGraph(g)
+		g.AddEdge(obj, stmt, &pgraph.SimpleEdge{Name: ""})
+	}
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *StmtFunc) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *StmtClass) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *StmtInclude) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *StmtImport) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *StmtComment) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprBool) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprStr) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprInt) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprFloat) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprList) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprMap) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprStruct) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprFunc) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+	if obj.Body != nil {
+		body, ok := obj.Body.(interfaces.ScopeGrapher)
+		if !ok {
+			panic("can't graph scope") // programming error
+		}
+		body.ScopeGraph(g)
+		g.AddEdge(obj, obj.Body, &pgraph.SimpleEdge{Name: "body"})
+	}
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprCall) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+	expr, ok := obj.expr.(interfaces.ScopeGrapher)
+	if !ok {
+		panic("can't graph scope") // programming error
+	}
+	expr.ScopeGraph(g)
+	g.AddEdge(obj, obj.expr, &pgraph.SimpleEdge{Name: "expr"})
+
+	for i, arg := range obj.Args {
+		arg, ok := arg.(interfaces.ScopeGrapher)
+		if !ok {
+			panic("can't graph scope") // programming error
+		}
+		arg.ScopeGraph(g)
+		g.AddEdge(obj, arg, &pgraph.SimpleEdge{Name: fmt.Sprintf("arg%d", i)})
+	}
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprVar) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+	target := obj.scope.Variables[obj.Name]
+	newTarget, ok := target.(interfaces.ScopeGrapher)
+	if !ok {
+		panic("can't graph scope") // programming error
+	}
+	newTarget.ScopeGraph(g)
+	g.AddEdge(obj, target, &pgraph.SimpleEdge{Name: "target"})
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprParam) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprPoly) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+	definition, ok := obj.Definition.(interfaces.ScopeGrapher)
+	if !ok {
+		panic("can't graph scope") // programming error
+	}
+	definition.ScopeGraph(g)
+	g.AddEdge(obj, obj.Definition, &pgraph.SimpleEdge{Name: "def"})
+}
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprIf) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}
diff --git a/lang/interfaces/ast.go b/lang/interfaces/ast.go
index cfba6ad4..ebb617f5 100644
--- a/lang/interfaces/ast.go
+++ b/lang/interfaces/ast.go
@@ -134,6 +134,15 @@ type Expr interface {
 	Value() (types.Value, error)
 }
 
+// ScopeGrapher adds a method to turn an AST (Expr or Stmt) into a graph so that
+// we can debug the SetScope compilation phase.
+type ScopeGrapher interface {
+	Node
+
+	// ScopeGraph adds nodes and vertices to the supplied graph.
+	ScopeGraph(g *pgraph.Graph)
+}
+
 // Data provides some data to the node that could be useful during its lifetime.
 type Data struct {
 	// Fs represents a handle to the filesystem that we're running on. This
diff --git a/lang/interfaces/structs.go b/lang/interfaces/structs.go
index 9a0ecdee..8ade67e0 100644
--- a/lang/interfaces/structs.go
+++ b/lang/interfaces/structs.go
@@ -187,3 +187,8 @@ func (obj *ExprAny) Value() (types.Value, error) {
 	}
 	return obj.V, nil
 }
+
+// ScopeGraph adds nodes and vertices to the supplied graph.
+func (obj *ExprAny) ScopeGraph(g *pgraph.Graph) {
+	g.AddVertex(obj)
+}