diff --git a/cmd/cue/cmd/common.go b/cmd/cue/cmd/common.go
index e8effa6..cbe713e 100644
--- a/cmd/cue/cmd/common.go
+++ b/cmd/cue/cmd/common.go
@@ -16,7 +16,6 @@
 
 import (
 	"bytes"
-	"fmt"
 	"io"
 	"os"
 	"path/filepath"
@@ -169,7 +168,7 @@
 
 type iterator interface {
 	scan() bool
-	instance() *cue.Instance
+	value() cue.Value
 	file() *ast.File // may return nil
 	err() error
 	close()
@@ -187,11 +186,11 @@
 	return i.i < len(i.a) && i.e == nil
 }
 
-func (i *instanceIterator) close()                  {}
-func (i *instanceIterator) err() error              { return i.e }
-func (i *instanceIterator) instance() *cue.Instance { return i.a[i.i] }
-func (i *instanceIterator) file() *ast.File         { return nil }
-func (i *instanceIterator) id() string              { return i.a[i.i].Dir }
+func (i *instanceIterator) close()           {}
+func (i *instanceIterator) err() error       { return i.e }
+func (i *instanceIterator) value() cue.Value { return i.a[i.i].Value() }
+func (i *instanceIterator) file() *ast.File  { return nil }
+func (i *instanceIterator) id() string       { return i.a[i.i].Dir }
 
 type streamingIterator struct {
 	r    *cue.Runtime
@@ -201,7 +200,7 @@
 	cfg  *encoding.Config
 	a    []*build.File
 	dec  *encoding.Decoder
-	i    *cue.Instance
+	v    cue.Value
 	f    *ast.File
 	e    error
 }
@@ -240,8 +239,8 @@
 	return i
 }
 
-func (i *streamingIterator) file() *ast.File         { return i.f }
-func (i *streamingIterator) instance() *cue.Instance { return i.i }
+func (i *streamingIterator) file() *ast.File  { return i.f }
+func (i *streamingIterator) value() cue.Value { return i.v }
 
 func (i *streamingIterator) id() string {
 	if i.inst != nil {
@@ -284,15 +283,12 @@
 		i.e = err
 		return false
 	}
-	i.i = inst
+	i.v = inst.Value()
 	if i.base.Exists() {
 		i.e = i.base.Err()
 		if i.e == nil {
-			i.i, i.e = i.i.Fill(i.base)
-			i.i.DisplayName = internal.DebugStr(i.b.schema)
-			if inst.DisplayName != "" {
-				i.i.DisplayName = fmt.Sprintf("%s|%s", inst.DisplayName, i.i.DisplayName)
-			}
+			i.v = i.v.Unify(i.base)
+			i.e = i.v.Err()
 		}
 		i.f = nil
 	}
@@ -339,15 +335,11 @@
 
 func (i *expressionIter) file() *ast.File { return nil }
 
-func (i *expressionIter) instance() *cue.Instance {
+func (i *expressionIter) value() cue.Value {
 	if len(i.expr) == 0 {
-		return i.iter.instance()
+		return i.iter.value()
 	}
-	inst := i.iter.instance()
-	v := i.iter.instance().Eval(i.expr[i.i])
-	ni := internal.MakeInstance(v).(*cue.Instance)
-	ni.DisplayName = fmt.Sprintf("%s|%s", inst.DisplayName, i.expr[i.i])
-	return ni
+	return internal.EvalExpr(i.iter.value(), i.expr[i.i]).(cue.Value)
 }
 
 type config struct {
diff --git a/cmd/cue/cmd/def.go b/cmd/cue/cmd/def.go
index bb21e4a..edba0e6 100644
--- a/cmd/cue/cmd/def.go
+++ b/cmd/cue/cmd/def.go
@@ -64,7 +64,7 @@
 			err := e.EncodeFile(f)
 			exitOnErr(cmd, err, true)
 		} else {
-			err := e.Encode(iter.instance())
+			err := e.Encode(iter.value())
 			exitOnErr(cmd, err, true)
 		}
 	}
diff --git a/cmd/cue/cmd/eval.go b/cmd/cue/cmd/eval.go
index 0d90deb..8cb676a 100644
--- a/cmd/cue/cmd/eval.go
+++ b/cmd/cue/cmd/eval.go
@@ -117,7 +117,7 @@
 		if len(b.insts) > 1 {
 			id = iter.id()
 		}
-		v := iter.instance().Value()
+		v := iter.value()
 
 		if flagConcrete.Bool(cmd) {
 			syn = append(syn, cue.Concrete(true))
diff --git a/cmd/cue/cmd/export.go b/cmd/cue/cmd/export.go
index 0f7669b..9a5e302 100644
--- a/cmd/cue/cmd/export.go
+++ b/cmd/cue/cmd/export.go
@@ -114,8 +114,8 @@
 	iter := b.instances()
 	defer iter.close()
 	for iter.scan() {
-		inst := iter.instance()
-		err = enc.Encode(inst)
+		v := iter.value()
+		err = enc.Encode(v)
 		exitOnErr(cmd, err, true)
 	}
 	exitOnErr(cmd, iter.err(), true)
diff --git a/cmd/cue/cmd/testdata/script/vet_embed.txt b/cmd/cue/cmd/testdata/script/vet_embed.txt
new file mode 100644
index 0000000..2ce8030
--- /dev/null
+++ b/cmd/cue/cmd/testdata/script/vet_embed.txt
@@ -0,0 +1,36 @@
+# Embedding at the file level should still close the package and validate
+# correctly against files from other packages without first merging these
+# files, thereby effectively embedding them and averting the closed check.
+
+# Issue #743
+
+! cue vet schema.cue foo.yaml
+cmp stderr expect-foo
+
+! cue vet schema.cue stream.yaml
+cmp stderr expect-stream
+
+-- schema.cue --
+package schema
+
+#Foo: {
+    a: int
+    b?: int
+}
+#Foo
+
+-- foo.yaml --
+a: 1
+c: 2
+
+-- stream.yaml --
+a: 1
+d: 2
+---
+a: 1
+e: 2
+
+-- expect-foo --
+field `c` not allowed
+-- expect-stream --
+field `d` not allowed
diff --git a/cmd/cue/cmd/vet.go b/cmd/cue/cmd/vet.go
index deb623d..b20a143 100644
--- a/cmd/cue/cmd/vet.go
+++ b/cmd/cue/cmd/vet.go
@@ -107,7 +107,7 @@
 	iter := b.instances()
 	defer iter.close()
 	for iter.scan() {
-		inst := iter.instance()
+		v := iter.value()
 		// TODO: use ImportPath or some other sanitized path.
 
 		concrete := true
@@ -124,9 +124,9 @@
 			cue.Hidden(true),
 		}
 		w := cmd.Stderr()
-		err := inst.Value().Validate(append(opt, cue.Concrete(concrete))...)
+		err := v.Validate(append(opt, cue.Concrete(concrete))...)
 		if err != nil && !hasFlag {
-			err = inst.Value().Validate(append(opt, cue.Concrete(false))...)
+			err = v.Validate(append(opt, cue.Concrete(false))...)
 			if !shown && err == nil {
 				shown = true
 				p := message.NewPrinter(getLang())
@@ -150,7 +150,7 @@
 	iter := b.instances()
 	defer iter.close()
 	for iter.scan() {
-		v := iter.instance().Value()
+		v := iter.value()
 
 		// Always concrete when checking against concrete files.
 		err := v.Validate(cue.Concrete(true))
diff --git a/internal/encoding/encoder.go b/internal/encoding/encoder.go
index f803d95..764d482 100644
--- a/internal/encoding/encoder.go
+++ b/internal/encoding/encoder.go
@@ -40,7 +40,7 @@
 type Encoder struct {
 	cfg          *Config
 	close        func() error
-	interpret    func(*cue.Instance) (*ast.File, error)
+	interpret    func(cue.Value) (*ast.File, error)
 	encFile      func(*ast.File) error
 	encValue     func(cue.Value) error
 	autoSimplify bool
@@ -79,7 +79,8 @@
 	case build.OpenAPI:
 		// TODO: get encoding options
 		cfg := &openapi.Config{}
-		e.interpret = func(i *cue.Instance) (*ast.File, error) {
+		e.interpret = func(v cue.Value) (*ast.File, error) {
+			i := internal.MakeInstance(v).(*cue.Instance)
 			return openapi.Generate(i, cfg)
 		}
 	// case build.JSONSchema:
@@ -204,26 +205,25 @@
 	return e.encodeFile(f, e.interpret)
 }
 
-func (e *Encoder) Encode(inst *cue.Instance) error {
+func (e *Encoder) Encode(v cue.Value) error {
 	e.autoSimplify = true
 	if e.interpret != nil {
-		f, err := e.interpret(inst)
+		f, err := e.interpret(v)
 		if err != nil {
 			return err
 		}
 		return e.encodeFile(f, nil)
 	}
-	v := inst.Value()
 	if err := v.Validate(cue.Concrete(e.concrete)); err != nil {
 		return err
 	}
 	if e.encValue != nil {
-		return e.encValue(inst.Value())
+		return e.encValue(v)
 	}
-	return e.encFile(valueToFile(inst.Value()))
+	return e.encFile(valueToFile(v))
 }
 
-func (e *Encoder) encodeFile(f *ast.File, interpret func(*cue.Instance) (*ast.File, error)) error {
+func (e *Encoder) encodeFile(f *ast.File, interpret func(cue.Value) (*ast.File, error)) error {
 	if interpret == nil && e.encFile != nil {
 		return e.encFile(f)
 	}
@@ -234,13 +234,13 @@
 		return err
 	}
 	if interpret != nil {
-		return e.Encode(inst)
+		return e.Encode(inst.Value())
 	}
 	v := inst.Value()
 	if err := v.Validate(cue.Concrete(e.concrete)); err != nil {
 		return err
 	}
-	return e.encValue(inst.Value())
+	return e.encValue(v)
 }
 
 func writer(f *build.File, cfg *Config) (_ io.Writer, close func() error, err error) {