diff --git a/cmd/dagger/cmd/compute.go b/cmd/dagger/cmd/compute.go
index 7cf7bfab..3c22b583 100644
--- a/cmd/dagger/cmd/compute.go
+++ b/cmd/dagger/cmd/compute.go
@@ -13,9 +13,6 @@ import (
 )
 
 var (
-	// FIXME: global shared cue compiler is a workaround to limitation in the cue API
-	//   This can be made cleaner by moving InputValue (or equivalent) under Env.
-	cc      = &dagger.Compiler{}
 	input   *dagger.InputValue
 	updater *dagger.InputValue
 )
@@ -35,7 +32,7 @@ var computeCmd = &cobra.Command{
 		lg := logger.New()
 		ctx := lg.WithContext(appcontext.Context())
 
-		env, err := dagger.NewEnv(cc)
+		env, err := dagger.NewEnv()
 		if err != nil {
 			lg.Fatal().Err(err).Msg("unable to initialize environment")
 		}
@@ -68,7 +65,7 @@ var computeCmd = &cobra.Command{
 func init() {
 	var err error
 	// Setup --input-* flags
-	input, err = dagger.NewInputValue(cc, "{}")
+	input, err = dagger.NewInputValue("{}")
 	if err != nil {
 		panic(err)
 	}
@@ -78,7 +75,7 @@ func init() {
 	computeCmd.Flags().Var(input.CueFlag(), "input-cue", "CUE")
 
 	// Setup (future) --from-* flags
-	updater, err = dagger.NewInputValue(cc, "[...{do:string, ...}]")
+	updater, err = dagger.NewInputValue("[...{do:string, ...}]")
 	if err != nil {
 		panic(err)
 	}
diff --git a/dagger/build.go b/dagger/build.go
new file mode 100644
index 00000000..2bdc8352
--- /dev/null
+++ b/dagger/build.go
@@ -0,0 +1,59 @@
+package dagger
+
+import (
+	"context"
+	"path"
+	"path/filepath"
+
+	cueerrors "cuelang.org/go/cue/errors"
+	cueload "cuelang.org/go/cue/load"
+	"github.com/pkg/errors"
+	"github.com/rs/zerolog/log"
+
+	"dagger.cloud/go/dagger/cc"
+)
+
+// Build a cue configuration tree from the files in fs.
+func CueBuild(ctx context.Context, fs FS, args ...string) (*cc.Value, error) {
+	lg := log.Ctx(ctx)
+
+	// The CUE overlay needs to be prefixed by a non-conflicting path with the
+	// local filesystem, otherwise Cue will merge the Overlay with whatever Cue
+	// files it finds locally.
+	const overlayPrefix = "/config"
+
+	buildConfig := &cueload.Config{
+		Dir:     overlayPrefix,
+		Overlay: map[string]cueload.Source{},
+	}
+	buildArgs := args
+
+	err := fs.Walk(ctx, func(p string, f Stat) error {
+		lg.Debug().Str("path", p).Msg("Compiler.Build: processing")
+		if f.IsDir() {
+			return nil
+		}
+		if filepath.Ext(p) != ".cue" {
+			return nil
+		}
+		contents, err := fs.ReadFile(ctx, p)
+		if err != nil {
+			return errors.Wrap(err, p)
+		}
+		overlayPath := path.Join(overlayPrefix, p)
+		buildConfig.Overlay[overlayPath] = cueload.FromBytes(contents)
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	instances := cueload.Instances(buildArgs, buildConfig)
+	if len(instances) != 1 {
+		return nil, errors.New("only one package is supported at a time")
+	}
+	inst, err := cc.Cue().Build(instances[0])
+	if err != nil {
+		return nil, errors.New(cueerrors.Details(err, &cueerrors.Config{}))
+	}
+	return cc.Wrap(inst.Value(), inst), nil
+}
diff --git a/dagger/cc/cc.go b/dagger/cc/cc.go
new file mode 100644
index 00000000..23eaac23
--- /dev/null
+++ b/dagger/cc/cc.go
@@ -0,0 +1,53 @@
+package cc
+
+import (
+	"cuelang.org/go/cue"
+
+	cueerrors "cuelang.org/go/cue/errors"
+	"github.com/pkg/errors"
+)
+
+var (
+	// Shared global compiler
+	cc = &Compiler{}
+)
+
+func Compile(name string, src interface{}) (*Value, error) {
+	return cc.Compile(name, src)
+}
+
+func EmptyStruct() (*Value, error) {
+	return cc.EmptyStruct()
+}
+
+// FIXME can be refactored away now?
+func Wrap(v cue.Value, inst *cue.Instance) *Value {
+	return cc.Wrap(v, inst)
+}
+
+func Cue() *cue.Runtime {
+	return cc.Cue()
+}
+
+func Err(err error) error {
+	if err == nil {
+		return nil
+	}
+	return errors.New(cueerrors.Details(err, &cueerrors.Config{}))
+}
+
+func Lock() {
+	cc.Lock()
+}
+
+func Unlock() {
+	cc.Unlock()
+}
+
+func RLock() {
+	cc.RLock()
+}
+
+func RUnlock() {
+	cc.RUnlock()
+}
diff --git a/dagger/cc/compiler.go b/dagger/cc/compiler.go
new file mode 100644
index 00000000..19820611
--- /dev/null
+++ b/dagger/cc/compiler.go
@@ -0,0 +1,40 @@
+package cc
+
+import (
+	"sync"
+
+	"cuelang.org/go/cue"
+)
+
+// Polyfill for a cue runtime
+// (we call it compiler to avoid confusion with dagger runtime)
+// Use this instead of cue.Runtime
+type Compiler struct {
+	sync.RWMutex
+	cue.Runtime
+}
+
+func (cc *Compiler) Cue() *cue.Runtime {
+	return &(cc.Runtime)
+}
+
+// Compile an empty struct
+func (cc *Compiler) EmptyStruct() (*Value, error) {
+	return cc.Compile("", "")
+}
+
+func (cc *Compiler) Compile(name string, src interface{}) (*Value, error) {
+	cc.Lock()
+	defer cc.Unlock()
+
+	inst, err := cc.Cue().Compile(name, src)
+	if err != nil {
+		// FIXME: cleaner way to unwrap cue error details?
+		return nil, Err(err)
+	}
+	return cc.Wrap(inst.Value(), inst), nil
+}
+
+func (cc *Compiler) Wrap(v cue.Value, inst *cue.Instance) *Value {
+	return wrapValue(v, inst)
+}
diff --git a/dagger/json.go b/dagger/cc/json.go
similarity index 99%
rename from dagger/json.go
rename to dagger/cc/json.go
index c0eaf767..9eef5fef 100644
--- a/dagger/json.go
+++ b/dagger/cc/json.go
@@ -1,4 +1,4 @@
-package dagger
+package cc
 
 import (
 	"fmt"
diff --git a/dagger/cc/utils.go b/dagger/cc/utils.go
new file mode 100644
index 00000000..bf2d6d29
--- /dev/null
+++ b/dagger/cc/utils.go
@@ -0,0 +1,22 @@
+package cc
+
+import (
+	"cuelang.org/go/cue"
+)
+
+func cueStringsToCuePath(parts ...string) cue.Path {
+	selectors := make([]cue.Selector, 0, len(parts))
+	for _, part := range parts {
+		selectors = append(selectors, cue.Str(part))
+	}
+	return cue.MakePath(selectors...)
+}
+
+func cuePathToStrings(p cue.Path) []string {
+	selectors := p.Selectors()
+	out := make([]string, len(selectors))
+	for i, sel := range selectors {
+		out[i] = sel.String()
+	}
+	return out
+}
diff --git a/dagger/value.go b/dagger/cc/value.go
similarity index 82%
rename from dagger/value.go
rename to dagger/cc/value.go
index c7073524..a5762b6d 100644
--- a/dagger/value.go
+++ b/dagger/cc/value.go
@@ -1,18 +1,14 @@
-package dagger
+package cc
 
 import (
-	"fmt"
-
 	"cuelang.org/go/cue"
 	cueformat "cuelang.org/go/cue/format"
-	"github.com/moby/buildkit/client/llb"
 )
 
 // Value is a wrapper around cue.Value.
 // Use instead of cue.Value and cue.Instance
 type Value struct {
 	val  cue.Value
-	cc   *Compiler
 	inst *cue.Instance
 }
 
@@ -21,21 +17,20 @@ func (v *Value) CueInst() *cue.Instance {
 }
 
 func (v *Value) Wrap(v2 cue.Value) *Value {
-	return wrapValue(v2, v.inst, v.cc)
+	return wrapValue(v2, v.inst)
 }
 
-func wrapValue(v cue.Value, inst *cue.Instance, cc *Compiler) *Value {
+func wrapValue(v cue.Value, inst *cue.Instance) *Value {
 	return &Value{
 		val:  v,
-		cc:   cc,
 		inst: inst,
 	}
 }
 
 // Fill the value in-place, unlike Merge which returns a copy.
 func (v *Value) Fill(x interface{}) error {
-	v.cc.Lock()
-	defer v.cc.Unlock()
+	cc.Lock()
+	defer cc.Unlock()
 
 	// If calling Fill() with a Value, we want to use the underlying
 	// cue.Value to fill.
@@ -49,8 +44,8 @@ func (v *Value) Fill(x interface{}) error {
 
 // LookupPath is a concurrency safe wrapper around cue.Value.LookupPath
 func (v *Value) LookupPath(p cue.Path) *Value {
-	v.cc.RLock()
-	defer v.cc.RUnlock()
+	cc.RLock()
+	defer cc.RUnlock()
 
 	return v.Wrap(v.val.LookupPath(p))
 }
@@ -142,9 +137,9 @@ func (v *Value) RangeStruct(fn func(string, *Value) error) error {
 //   1. Check that the value matches the spec.
 //   2. Merge the value and the spec, and return the result.
 func (v *Value) Finalize(spec *Value) (*Value, error) {
-	v.cc.Lock()
+	cc.Lock()
 	unified := spec.val.Unify(v.val)
-	v.cc.Unlock()
+	cc.Unlock()
 	// FIXME: temporary debug message, remove before merging.
 	//      fmt.Printf("Finalize:\n  spec=%v\n  v=%v\n  unified=%v", spec.val, v.val, unified)
 
@@ -155,7 +150,7 @@ func (v *Value) Finalize(spec *Value) (*Value, error) {
 	// fix on top (we access individual fields so have an opportunity
 	//  to return an error if they are not there).
 	if err := unified.Validate(cue.Final()); err != nil {
-		return nil, cueErr(err)
+		return nil, Err(err)
 	}
 	return v.Merge(spec)
 }
@@ -163,15 +158,12 @@ func (v *Value) Finalize(spec *Value) (*Value, error) {
 // FIXME: receive string path?
 func (v *Value) Merge(x interface{}, path ...string) (*Value, error) {
 	if xval, ok := x.(*Value); ok {
-		if xval.cc != v.cc {
-			return nil, fmt.Errorf("can't merge values from different compilers")
-		}
 		x = xval.val
 	}
 
-	v.cc.Lock()
+	cc.Lock()
 	result := v.Wrap(v.val.Fill(x, path...))
-	v.cc.Unlock()
+	cc.Unlock()
 
 	return result, result.Validate()
 }
@@ -234,48 +226,16 @@ func (v *Value) JSON() JSON {
 	return out
 }
 
-func (v *Value) SaveJSON(fs FS, filename string) FS {
-	return fs.Change(func(st llb.State) llb.State {
-		return st.File(
-			llb.Mkfile(filename, 0600, v.JSON()),
-		)
-	})
-}
-
-func (v *Value) Save(fs FS, filename string) (FS, error) {
-	src, err := v.Source()
-	if err != nil {
-		return fs, err
-	}
-	return fs.Change(func(st llb.State) llb.State {
-		return st.File(
-			llb.Mkfile(filename, 0600, src),
-		)
-	}), nil
-}
-
 // Check that a value is valid. Optionally check that it matches
 // all the specified spec definitions..
-func (v *Value) Validate(defs ...string) error {
-	if err := v.val.Validate(); err != nil {
-		return err
-	}
-	if len(defs) == 0 {
-		return nil
-	}
-	spec := v.cc.Spec()
-	for _, def := range defs {
-		if err := spec.Validate(v, def); err != nil {
-			return err
-		}
-	}
-	return nil
+func (v *Value) Validate() error {
+	return v.val.Validate()
 }
 
 // Return cue source for this value
 func (v *Value) Source() ([]byte, error) {
-	v.cc.RLock()
-	defer v.cc.RUnlock()
+	cc.RLock()
+	defer cc.RUnlock()
 
 	return cueformat.Node(v.val.Eval().Syntax())
 }
@@ -294,3 +254,7 @@ func (v *Value) IsEmptyStruct() bool {
 	}
 	return false
 }
+
+func (v *Value) Cue() cue.Value {
+	return v.val
+}
diff --git a/dagger/client.go b/dagger/client.go
index 9c6c802c..1b851a72 100644
--- a/dagger/client.go
+++ b/dagger/client.go
@@ -23,6 +23,8 @@ import (
 	// docker output
 	"github.com/containerd/console"
 	"github.com/moby/buildkit/util/progress/progressui"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 const (
@@ -50,8 +52,8 @@ func NewClient(ctx context.Context, host string) (*Client, error) {
 	}, nil
 }
 
-// FIXME: return completed *Env, instead of *Value
-func (c *Client) Compute(ctx context.Context, env *Env) (*Value, error) {
+// FIXME: return completed *Env, instead of *cc.Value
+func (c *Client) Compute(ctx context.Context, env *Env) (*cc.Value, error) {
 	lg := log.Ctx(ctx)
 
 	eg, gctx := errgroup.WithContext(ctx)
@@ -75,16 +77,16 @@ func (c *Client) Compute(ctx context.Context, env *Env) (*Value, error) {
 
 	// Spawn output retriever
 	var (
-		out *Value
+		out *cc.Value
 		err error
 	)
 	eg.Go(func() error {
 		defer outr.Close()
-		out, err = c.outputfn(gctx, outr, env.cc)
+		out, err = c.outputfn(gctx, outr)
 		return err
 	})
 
-	return out, cueErr(eg.Wait())
+	return out, cc.Err(eg.Wait())
 }
 
 func (c *Client) buildfn(ctx context.Context, env *Env, ch chan *bk.SolveStatus, w io.WriteCloser) error {
@@ -158,7 +160,7 @@ func (c *Client) buildfn(ctx context.Context, env *Env, ch chan *bk.SolveStatus,
 }
 
 // Read tar export stream from buildkit Build(), and extract cue output
-func (c *Client) outputfn(ctx context.Context, r io.Reader, cc *Compiler) (*Value, error) {
+func (c *Client) outputfn(ctx context.Context, r io.Reader) (*cc.Value, error) {
 	lg := log.Ctx(ctx)
 
 	// FIXME: merge this into env output.
diff --git a/dagger/compiler.go b/dagger/compiler.go
deleted file mode 100644
index ba84590f..00000000
--- a/dagger/compiler.go
+++ /dev/null
@@ -1,120 +0,0 @@
-//go:generate sh gen.sh
-package dagger
-
-import (
-	"context"
-	"path"
-	"path/filepath"
-	"sync"
-
-	"cuelang.org/go/cue"
-	cueerrors "cuelang.org/go/cue/errors"
-	cueload "cuelang.org/go/cue/load"
-	"github.com/pkg/errors"
-	"github.com/rs/zerolog/log"
-)
-
-// Polyfill for a cue runtime
-// (we call it compiler to avoid confusion with dagger runtime)
-// Use this instead of cue.Runtime
-type Compiler struct {
-	sync.RWMutex
-	cue.Runtime
-	spec *Spec
-}
-
-func (cc *Compiler) Cue() *cue.Runtime {
-	return &(cc.Runtime)
-}
-
-func (cc *Compiler) Spec() *Spec {
-	if cc.spec != nil {
-		return cc.spec
-	}
-	v, err := cc.Compile("spec.cue", DaggerSpec)
-	if err != nil {
-		panic(err)
-	}
-	cc.spec, err = newSpec(v)
-	if err != nil {
-		panic(err)
-	}
-	return cc.spec
-}
-
-// Compile an empty struct
-func (cc *Compiler) EmptyStruct() (*Value, error) {
-	return cc.Compile("", "")
-}
-
-func (cc *Compiler) Compile(name string, src interface{}) (*Value, error) {
-	cc.Lock()
-	defer cc.Unlock()
-
-	inst, err := cc.Cue().Compile(name, src)
-	if err != nil {
-		// FIXME: cleaner way to unwrap cue error details?
-		return nil, cueErr(err)
-	}
-	return cc.Wrap(inst.Value(), inst), nil
-}
-
-// Compile a cue configuration, and load it as a script.
-// If the cue configuration is invalid, or does not match the script spec,
-//  return an error.
-func (cc *Compiler) CompileScript(name string, src interface{}) (*Script, error) {
-	v, err := cc.Compile(name, src)
-	if err != nil {
-		return nil, err
-	}
-	return NewScript(v)
-}
-
-// Build a cue configuration tree from the files in fs.
-func (cc *Compiler) Build(ctx context.Context, fs FS, args ...string) (*Value, error) {
-	lg := log.Ctx(ctx)
-
-	// The CUE overlay needs to be prefixed by a non-conflicting path with the
-	// local filesystem, otherwise Cue will merge the Overlay with whatever Cue
-	// files it finds locally.
-	const overlayPrefix = "/config"
-
-	buildConfig := &cueload.Config{
-		Dir:     overlayPrefix,
-		Overlay: map[string]cueload.Source{},
-	}
-	buildArgs := args
-
-	err := fs.Walk(ctx, func(p string, f Stat) error {
-		lg.Debug().Str("path", p).Msg("Compiler.Build: processing")
-		if f.IsDir() {
-			return nil
-		}
-		if filepath.Ext(p) != ".cue" {
-			return nil
-		}
-		contents, err := fs.ReadFile(ctx, p)
-		if err != nil {
-			return errors.Wrap(err, p)
-		}
-		overlayPath := path.Join(overlayPrefix, p)
-		buildConfig.Overlay[overlayPath] = cueload.FromBytes(contents)
-		return nil
-	})
-	if err != nil {
-		return nil, err
-	}
-	instances := cueload.Instances(buildArgs, buildConfig)
-	if len(instances) != 1 {
-		return nil, errors.New("only one package is supported at a time")
-	}
-	inst, err := cc.Cue().Build(instances[0])
-	if err != nil {
-		return nil, errors.New(cueerrors.Details(err, &cueerrors.Config{}))
-	}
-	return cc.Wrap(inst.Value(), inst), nil
-}
-
-func (cc *Compiler) Wrap(v cue.Value, inst *cue.Instance) *Value {
-	return wrapValue(v, inst, cc)
-}
diff --git a/dagger/component.go b/dagger/component.go
index a1e4d1de..4644413c 100644
--- a/dagger/component.go
+++ b/dagger/component.go
@@ -4,16 +4,17 @@ import (
 	"context"
 	"os"
 
+	"dagger.cloud/go/dagger/cc"
 	"github.com/pkg/errors"
 )
 
 type Component struct {
 	// Source value for the component, without spec merged
 	// eg. `{ string, #dagger: compute: [{do:"fetch-container", ...}]}`
-	v *Value
+	v *cc.Value
 }
 
-func NewComponent(v *Value) (*Component, error) {
+func NewComponent(v *cc.Value) (*Component, error) {
 	if !v.Exists() {
 		// Component value does not exist
 		return nil, ErrNotExist
@@ -23,7 +24,7 @@ func NewComponent(v *Value) (*Component, error) {
 		return nil, ErrNotExist
 	}
 	// Validate & merge with spec
-	final, err := v.Finalize(v.cc.Spec().Get("#Component"))
+	final, err := v.Finalize(spec.Get("#Component"))
 	if err != nil {
 		return nil, errors.Wrap(err, "invalid component")
 	}
@@ -32,12 +33,12 @@ func NewComponent(v *Value) (*Component, error) {
 	}, nil
 }
 
-func (c *Component) Value() *Value {
+func (c *Component) Value() *cc.Value {
 	return c.v
 }
 
 // Return the contents of the "#dagger" annotation.
-func (c *Component) Config() *Value {
+func (c *Component) Config() *cc.Value {
 	return c.Value().Get("#dagger")
 }
 
@@ -78,7 +79,7 @@ func (c *Component) Compute(ctx context.Context, s Solver, out *Fillable) (FS, e
 
 // A component implements the Executable interface by returning its
 // compute script.
-// See Value.Executable().
+// See cc.Value.Executable().
 func (c *Component) Execute(ctx context.Context, fs FS, out *Fillable) (FS, error) {
 	script, err := c.ComputeScript()
 	if err != nil {
diff --git a/dagger/component_test.go b/dagger/component_test.go
index a206d857..e7e3db41 100644
--- a/dagger/component_test.go
+++ b/dagger/component_test.go
@@ -3,10 +3,11 @@ package dagger
 import (
 	"context"
 	"testing"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 func TestComponentNotExist(t *testing.T) {
-	cc := &Compiler{}
 	root, err := cc.Compile("root.cue", `
 foo: hello: "world"
 `)
@@ -24,7 +25,6 @@ foo: hello: "world"
 }
 
 func TestLoadEmptyComponent(t *testing.T) {
-	cc := &Compiler{}
 	root, err := cc.Compile("root.cue", `
 foo: #dagger: {}
 `)
@@ -40,7 +40,6 @@ foo: #dagger: {}
 // Test that default values in spec are applied at the component level
 // See issue #19
 func TestComponentDefaults(t *testing.T) {
-	cc := &Compiler{}
 	v, err := cc.Compile("", `
 #dagger: compute: [
 	{
@@ -79,7 +78,6 @@ func TestComponentDefaults(t *testing.T) {
 }
 
 func TestValidateEmptyComponent(t *testing.T) {
-	cc := &Compiler{}
 	v, err := cc.Compile("", "#dagger: compute: _")
 	if err != nil {
 		t.Fatal(err)
@@ -91,7 +89,6 @@ func TestValidateEmptyComponent(t *testing.T) {
 }
 
 func TestValidateSimpleComponent(t *testing.T) {
-	cc := &Compiler{}
 	v, err := cc.Compile("", `hello: "world", #dagger: { compute: [{do:"local",dir:"foo"}]}`)
 	if err != nil {
 		t.Fatal(err)
diff --git a/dagger/env.go b/dagger/env.go
index 24f665e0..63a1636a 100644
--- a/dagger/env.go
+++ b/dagger/env.go
@@ -8,6 +8,8 @@ import (
 	cueflow "cuelang.org/go/tools/flow"
 	"github.com/pkg/errors"
 	"github.com/rs/zerolog/log"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 type Env struct {
@@ -20,19 +22,16 @@ type Env struct {
 	updater *Script
 
 	// Layer 1: base configuration
-	base *Value
+	base *cc.Value
 
 	// Layer 2: user inputs
-	input *Value
+	input *cc.Value
 
 	// Layer 3: computed values
-	output *Value
+	output *cc.Value
 
 	// All layers merged together: base + input + output
-	state *Value
-
-	// Use the same cue compiler for everything
-	cc *Compiler
+	state *cc.Value
 }
 
 func (env *Env) Updater() *Script {
@@ -42,10 +41,10 @@ func (env *Env) Updater() *Script {
 // Set the updater script for this environment.
 // u may be:
 //  - A compiled script: *Script
-//  - A compiled value: *Value
+//  - A compiled value: *cc.Value
 //  - A cue source: string, []byte, io.Reader
 func (env *Env) SetUpdater(u interface{}) error {
-	if v, ok := u.(*Value); ok {
+	if v, ok := u.(*cc.Value); ok {
 		updater, err := NewScript(v)
 		if err != nil {
 			return errors.Wrap(err, "invalid updater script")
@@ -60,7 +59,7 @@ func (env *Env) SetUpdater(u interface{}) error {
 	if u == nil {
 		u = "[]"
 	}
-	updater, err := env.cc.CompileScript("updater", u)
+	updater, err := CompileScript("updater", u)
 	if err != nil {
 		return err
 	}
@@ -68,16 +67,12 @@ func (env *Env) SetUpdater(u interface{}) error {
 	return nil
 }
 
-func NewEnv(cc *Compiler) (*Env, error) {
-	if cc == nil {
-		cc = &Compiler{}
-	}
+func NewEnv() (*Env, error) {
 	empty, err := cc.EmptyStruct()
 	if err != nil {
 		return nil, err
 	}
 	env := &Env{
-		cc:     cc,
 		base:   empty,
 		input:  empty,
 		output: empty,
@@ -89,20 +84,16 @@ func NewEnv(cc *Compiler) (*Env, error) {
 	return env, nil
 }
 
-func (env *Env) Compiler() *Compiler {
-	return env.cc
-}
-
-func (env *Env) State() *Value {
+func (env *Env) State() *cc.Value {
 	return env.state
 }
 
-func (env *Env) Input() *Value {
+func (env *Env) Input() *cc.Value {
 	return env.input
 }
 
 func (env *Env) SetInput(i interface{}) error {
-	if input, ok := i.(*Value); ok {
+	if input, ok := i.(*cc.Value); ok {
 		return env.set(
 			env.base,
 			input,
@@ -112,7 +103,7 @@ func (env *Env) SetInput(i interface{}) error {
 	if i == nil {
 		i = "{}"
 	}
-	input, err := env.cc.Compile("input", i)
+	input, err := cc.Compile("input", i)
 	if err != nil {
 		return err
 	}
@@ -132,7 +123,7 @@ func (env *Env) Update(ctx context.Context, s Solver) error {
 	}
 	// load cue files produced by updater
 	// FIXME: BuildAll() to force all files (no required package..)
-	base, err := env.cc.Build(ctx, src)
+	base, err := CueBuild(ctx, src)
 	if err != nil {
 		return errors.Wrap(err, "base config")
 	}
@@ -143,11 +134,11 @@ func (env *Env) Update(ctx context.Context, s Solver) error {
 	)
 }
 
-func (env *Env) Base() *Value {
+func (env *Env) Base() *cc.Value {
 	return env.base
 }
 
-func (env *Env) Output() *Value {
+func (env *Env) Output() *cc.Value {
 	return env.output
 }
 
@@ -195,7 +186,7 @@ func (env *Env) LocalDirs(ctx context.Context) (map[string]string, error) {
 func (env *Env) Components() []*Component {
 	components := []*Component{}
 	env.State().Walk(
-		func(v *Value) bool {
+		func(v *cc.Value) bool {
 			c, err := NewComponent(v)
 			if os.IsNotExist(err) {
 				return true
@@ -211,30 +202,30 @@ func (env *Env) Components() []*Component {
 	return components
 }
 
-// FIXME: this is just a 3-way merge. Add var args to Value.Merge.
-func (env *Env) set(base, input, output *Value) (err error) {
-	// FIXME: make this cleaner in *Value by keeping intermediary instances
+// FIXME: this is just a 3-way merge. Add var args to cc.Value.Merge.
+func (env *Env) set(base, input, output *cc.Value) (err error) {
+	// FIXME: make this cleaner in *cc.Value by keeping intermediary instances
 	// FIXME: state.CueInst() must return an instance with the same
 	//  contents as state.v, for the purposes of cueflow.
-	//  That is not currently how *Value works, so we prepare the cue
+	//  That is not currently how *cc.Value works, so we prepare the cue
 	//  instance manually.
-	//   --> refactor the Value API to do this for us.
+	//   --> refactor the cc.Value API to do this for us.
 	stateInst := env.state.CueInst()
 
-	stateInst, err = stateInst.Fill(base.val)
+	stateInst, err = stateInst.Fill(base.Cue())
 	if err != nil {
 		return errors.Wrap(err, "merge base & input")
 	}
-	stateInst, err = stateInst.Fill(input.val)
+	stateInst, err = stateInst.Fill(input.Cue())
 	if err != nil {
 		return errors.Wrap(err, "merge base & input")
 	}
-	stateInst, err = stateInst.Fill(output.val)
+	stateInst, err = stateInst.Fill(output.Cue())
 	if err != nil {
 		return errors.Wrap(err, "merge output with base & input")
 	}
 
-	state := env.cc.Wrap(stateInst.Value(), stateInst)
+	state := cc.Wrap(stateInst.Value(), stateInst)
 
 	// commit
 	env.base = base
@@ -248,9 +239,9 @@ func (env *Env) set(base, input, output *Value) (err error) {
 // (Use with FS.Change)
 func (env *Env) Export(fs FS) (FS, error) {
 	// FIXME: we serialize as JSON to guarantee a self-contained file.
-	//   Value.Save() leaks imports, so requires a shared cue.mod with
+	//   cc.Value.Save() leaks imports, so requires a shared cue.mod with
 	//   client which is undesirable.
-	//   Once Value.Save() resolves non-builtin imports with a tree shake,
+	//   Once cc.Value.Save() resolves non-builtin imports with a tree shake,
 	//   we can use it here.
 
 	// FIXME: Exporting base/input/output separately causes merge errors.
@@ -272,7 +263,7 @@ func (env *Env) Export(fs FS) (FS, error) {
 			return fs, err
 		}
 	}
-	fs = state.SaveJSON(fs, "state.cue")
+	fs = fs.WriteValueJSON("state.cue", state)
 	return fs, nil
 }
 
@@ -284,11 +275,11 @@ func (env *Env) Compute(ctx context.Context, s Solver) error {
 	flowInst := env.state.CueInst()
 	lg.
 		Debug().
-		Str("value", env.cc.Wrap(flowInst.Value(), flowInst).JSON().String()).
+		Str("value", cc.Wrap(flowInst.Value(), flowInst).JSON().String()).
 		Msg("walking")
 
 	// Initialize empty output
-	output, err := env.cc.EmptyStruct()
+	output, err := cc.EmptyStruct()
 	if err != nil {
 		return err
 	}
@@ -326,7 +317,7 @@ func (env *Env) Compute(ctx context.Context, s Solver) error {
 	}
 	// Cueflow match func
 	flowMatchFn := func(v cue.Value) (cueflow.Runner, error) {
-		if _, err := NewComponent(env.cc.Wrap(v, flowInst)); err != nil {
+		if _, err := NewComponent(cc.Wrap(v, flowInst)); err != nil {
 			if os.IsNotExist(err) {
 				// Not a component: skip
 				return nil, nil
@@ -340,7 +331,7 @@ func (env *Env) Compute(ctx context.Context, s Solver) error {
 				Logger()
 			ctx := lg.WithContext(ctx)
 
-			c, err := NewComponent(env.cc.Wrap(t.Value(), flowInst))
+			c, err := NewComponent(cc.Wrap(t.Value(), flowInst))
 			if err != nil {
 				return err
 			}
diff --git a/dagger/env_test.go b/dagger/env_test.go
index c09b6426..d77748dc 100644
--- a/dagger/env_test.go
+++ b/dagger/env_test.go
@@ -3,10 +3,12 @@ package dagger
 import (
 	"context"
 	"testing"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 func TestSimpleEnvSet(t *testing.T) {
-	env, err := NewEnv(nil)
+	env, err := NewEnv()
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -23,12 +25,12 @@ func TestSimpleEnvSet(t *testing.T) {
 }
 
 func TestSimpleEnvSetFromInputValue(t *testing.T) {
-	env, err := NewEnv(nil)
+	env, err := NewEnv()
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	v, err := env.Compiler().Compile("", `hello: "world"`)
+	v, err := cc.Compile("", `hello: "world"`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -45,12 +47,12 @@ func TestSimpleEnvSetFromInputValue(t *testing.T) {
 }
 
 func TestEnvInputComponent(t *testing.T) {
-	env, err := NewEnv(nil)
+	env, err := NewEnv()
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	v, err := env.Compiler().Compile("", `foo: #dagger: compute: [{do:"local",dir:"."}]`)
+	v, err := cc.Compile("", `foo: #dagger: compute: [{do:"local",dir:"."}]`)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/dagger/fs.go b/dagger/fs.go
index 1dd365f4..3234deac 100644
--- a/dagger/fs.go
+++ b/dagger/fs.go
@@ -10,6 +10,8 @@ import (
 	bkgw "github.com/moby/buildkit/frontend/gateway/client"
 	"github.com/pkg/errors"
 	fstypes "github.com/tonistiigi/fsutil/types"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 type Stat struct {
@@ -25,6 +27,26 @@ type FS struct {
 	s Solver
 }
 
+func (fs FS) WriteValueJSON(filename string, v *cc.Value) FS {
+	return fs.Change(func(st llb.State) llb.State {
+		return st.File(
+			llb.Mkfile(filename, 0600, v.JSON()),
+		)
+	})
+}
+
+func (fs FS) WriteValueCUE(filename string, v *cc.Value) (FS, error) {
+	src, err := v.Source()
+	if err != nil {
+		return fs, err
+	}
+	return fs.Change(func(st llb.State) llb.State {
+		return st.File(
+			llb.Mkfile(filename, 0600, src),
+		)
+	}), nil
+}
+
 func (fs FS) Solver() Solver {
 	return fs.s
 }
diff --git a/dagger/input.go b/dagger/input.go
index b0bf1ba4..42f9ca17 100644
--- a/dagger/input.go
+++ b/dagger/input.go
@@ -8,16 +8,17 @@ import (
 
 	"cuelang.org/go/cue"
 	"github.com/spf13/pflag"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 // A mutable cue value with an API suitable for user inputs,
 // such as command-line flag parsing.
 type InputValue struct {
-	root *Value
-	cc   *Compiler
+	root *cc.Value
 }
 
-func (iv *InputValue) Value() *Value {
+func (iv *InputValue) Value() *cc.Value {
 	return iv.root
 }
 
@@ -26,21 +27,20 @@ func (iv *InputValue) String() string {
 	return s
 }
 
-func NewInputValue(cc *Compiler, base interface{}) (*InputValue, error) {
+func NewInputValue(base interface{}) (*InputValue, error) {
 	root, err := cc.Compile("base", base)
 	if err != nil {
 		return nil, err
 	}
 	return &InputValue{
-		cc:   cc,
 		root: root,
 	}, nil
 }
 
-func (iv *InputValue) Set(s string, enc func(string, *Compiler) (interface{}, error)) error {
+func (iv *InputValue) Set(s string, enc func(string) (interface{}, error)) error {
 	// Split from eg. 'foo.bar={bla:"bla"}`
 	k, vRaw := splitkv(s)
-	v, err := enc(vRaw, iv.cc)
+	v, err := enc(vRaw)
 	if err != nil {
 		return err
 	}
@@ -64,7 +64,7 @@ type stringFlag struct {
 }
 
 func (sf stringFlag) Set(s string) error {
-	return sf.iv.Set(s, func(s string, _ *Compiler) (interface{}, error) {
+	return sf.iv.Set(s, func(s string) (interface{}, error) {
 		return s, nil
 	})
 }
@@ -95,7 +95,7 @@ type dirFlag struct {
 }
 
 func (f dirFlag) Set(s string) error {
-	return f.iv.Set(s, func(s string, cc *Compiler) (interface{}, error) {
+	return f.iv.Set(s, func(s string) (interface{}, error) {
 		// FIXME: this is a hack because cue API can't merge into a list
 		include, err := json.Marshal(f.include)
 		if err != nil {
@@ -130,7 +130,7 @@ type gitFlag struct {
 }
 
 func (f gitFlag) Set(s string) error {
-	return f.iv.Set(s, func(s string, cc *Compiler) (interface{}, error) {
+	return f.iv.Set(s, func(s string) (interface{}, error) {
 		u, err := url.Parse(s)
 		if err != nil {
 			return nil, fmt.Errorf("invalid git url")
@@ -170,7 +170,7 @@ type sourceFlag struct {
 }
 
 func (f sourceFlag) Set(s string) error {
-	return f.iv.Set(s, func(s string, cc *Compiler) (interface{}, error) {
+	return f.iv.Set(s, func(s string) (interface{}, error) {
 		u, err := url.Parse(s)
 		if err != nil {
 			return nil, err
@@ -209,7 +209,7 @@ type cueFlag struct {
 }
 
 func (f cueFlag) Set(s string) error {
-	return f.iv.Set(s, func(s string, cc *Compiler) (interface{}, error) {
+	return f.iv.Set(s, func(s string) (interface{}, error) {
 		return cc.Compile("cue input", s)
 	})
 }
diff --git a/dagger/input_test.go b/dagger/input_test.go
index d7172edc..8f919ed5 100644
--- a/dagger/input_test.go
+++ b/dagger/input_test.go
@@ -6,12 +6,12 @@ import (
 )
 
 func TestEnvInputFlag(t *testing.T) {
-	env, err := NewEnv(nil)
+	env, err := NewEnv()
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	input, err := NewInputValue(env.Compiler(), `{}`)
+	input, err := NewInputValue(`{}`)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/dagger/mount.go b/dagger/mount.go
index 790d5ed1..da162047 100644
--- a/dagger/mount.go
+++ b/dagger/mount.go
@@ -5,14 +5,16 @@ import (
 
 	"github.com/moby/buildkit/client/llb"
 	"github.com/pkg/errors"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 type Mount struct {
 	dest string
-	v    *Value
+	v    *cc.Value
 }
 
-func newMount(v *Value, dest string) (*Mount, error) {
+func newMount(v *cc.Value, dest string) (*Mount, error) {
 	if !v.Exists() {
 		return nil, ErrNotExist
 	}
@@ -22,19 +24,15 @@ func newMount(v *Value, dest string) (*Mount, error) {
 	}, nil
 }
 
-func (mnt *Mount) Validate(defs ...string) error {
-	return mnt.v.Validate(append(defs, "#Mount")...)
-}
-
 func (mnt *Mount) LLB(ctx context.Context, s Solver) (llb.RunOption, error) {
-	if err := mnt.Validate("#MountTmp"); err == nil {
+	if err := spec.Validate(mnt.v, "#MountTmp"); err == nil {
 		return llb.AddMount(
 			mnt.dest,
 			llb.Scratch(),
 			llb.Tmpfs(),
 		), nil
 	}
-	if err := mnt.Validate("#MountCache"); err == nil {
+	if err := spec.Validate(mnt.v, "#MountCache"); err == nil {
 		return llb.AddMount(
 			mnt.dest,
 			llb.Scratch(),
diff --git a/dagger/op.go b/dagger/op.go
index 9a91da0c..f31d60b0 100644
--- a/dagger/op.go
+++ b/dagger/op.go
@@ -9,15 +9,16 @@ import (
 	"github.com/pkg/errors"
 	"github.com/rs/zerolog/log"
 	"gopkg.in/yaml.v3"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 type Op struct {
-	v *Value
+	v *cc.Value
 }
 
-func NewOp(v *Value) (*Op, error) {
-	spec := v.cc.Spec().Get("#Op")
-	final, err := spec.Merge(v)
+func NewOp(v *cc.Value) (*Op, error) {
+	final, err := spec.Get("#Op").Merge(v)
 	if err != nil {
 		return nil, errors.Wrap(err, "invalid op")
 	}
@@ -25,7 +26,8 @@ func NewOp(v *Value) (*Op, error) {
 }
 
 // Same as newOp, but without spec merge + validation.
-func newOp(v *Value) (*Op, error) {
+func newOp(v *cc.Value) (*Op, error) {
+	// Exists() appears to be buggy, is it needed here?
 	if !v.Exists() {
 		return nil, ErrNotExist
 	}
@@ -57,7 +59,7 @@ func (op *Op) Walk(ctx context.Context, fn func(*Op) error) error {
 		// FIXME: we tolerate "from" which is not executable
 	}
 	if err := op.Validate("#Exec"); err == nil {
-		return op.Get("mount").RangeStruct(func(k string, v *Value) error {
+		return op.Get("mount").RangeStruct(func(k string, v *cc.Value) error {
 			if from, err := newExecutable(op.Get("from")); err == nil {
 				if err := from.Walk(ctx, fn); err != nil {
 					return err
@@ -104,9 +106,11 @@ func (op *Op) Action() (Action, error) {
 	return nil, fmt.Errorf("invalid operation: %s", op.v.JSON())
 }
 
-func (op *Op) Validate(defs ...string) error {
-	defs = append(defs, "#Op")
-	return op.v.Validate(defs...)
+func (op *Op) Validate(def string) error {
+	if err := spec.Validate(op.v, "#Op"); err != nil {
+		return err
+	}
+	return spec.Validate(op.v, def)
 }
 
 func (op *Op) Subdir(ctx context.Context, fs FS, out *Fillable) (FS, error) {
@@ -212,7 +216,7 @@ func (op *Op) Exec(ctx context.Context, fs FS, out *Fillable) (FS, error) {
 	}
 	// mounts
 	if mounts := op.v.Lookup("mount"); mounts.Exists() {
-		if err := mounts.RangeStruct(func(k string, v *Value) error {
+		if err := mounts.RangeStruct(func(k string, v *cc.Value) error {
 			mnt, err := newMount(v, k)
 			if err != nil {
 				return err
@@ -345,6 +349,6 @@ func (op *Op) FetchGit(ctx context.Context, fs FS, out *Fillable) (FS, error) {
 	return fs.Set(llb.Git(remote, ref)), nil // lazy solve
 }
 
-func (op *Op) Get(target string) *Value {
+func (op *Op) Get(target string) *cc.Value {
 	return op.v.Get(target)
 }
diff --git a/dagger/op_test.go b/dagger/op_test.go
index b67cb8c9..3f58c21a 100644
--- a/dagger/op_test.go
+++ b/dagger/op_test.go
@@ -3,12 +3,13 @@ package dagger
 import (
 	"context"
 	"testing"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 func TestLocalMatch(t *testing.T) {
 	ctx := context.TODO()
 
-	cc := &Compiler{}
 	src := `do: "local", dir: "foo"`
 	v, err := cc.Compile("", src)
 	if err != nil {
@@ -34,7 +35,6 @@ func TestLocalMatch(t *testing.T) {
 func TestCopyMatch(t *testing.T) {
 	ctx := context.TODO()
 
-	cc := &Compiler{}
 	src := `do: "copy", from: [{do: "local", dir: "foo"}]`
 	v, err := cc.Compile("", src)
 	if err != nil {
diff --git a/dagger/script.go b/dagger/script.go
index c744e7ac..a0c3a2ba 100644
--- a/dagger/script.go
+++ b/dagger/script.go
@@ -6,6 +6,8 @@ import (
 	"cuelang.org/go/cue"
 	"github.com/pkg/errors"
 	"github.com/rs/zerolog/log"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 var (
@@ -13,12 +15,23 @@ var (
 )
 
 type Script struct {
-	v *Value
+	v *cc.Value
 }
 
-func NewScript(v *Value) (*Script, error) {
+// Compile a cue configuration, and load it as a script.
+// If the cue configuration is invalid, or does not match the script spec,
+//  return an error.
+func CompileScript(name string, src interface{}) (*Script, error) {
+	v, err := cc.Compile(name, src)
+	if err != nil {
+		return nil, err
+	}
+	return NewScript(v)
+}
+
+func NewScript(v *cc.Value) (*Script, error) {
 	// Validate & merge with spec
-	final, err := v.Finalize(v.cc.Spec().Get("#Script"))
+	final, err := v.Finalize(spec.Get("#Script"))
 	if err != nil {
 		return nil, errors.Wrap(err, "invalid script")
 	}
@@ -26,7 +39,7 @@ func NewScript(v *Value) (*Script, error) {
 }
 
 // Same as newScript, but without spec merge + validation.
-func newScript(v *Value) (*Script, error) {
+func newScript(v *cc.Value) (*Script, error) {
 	if !v.Exists() {
 		return nil, ErrNotExist
 	}
@@ -35,7 +48,7 @@ func newScript(v *Value) (*Script, error) {
 	}, nil
 }
 
-func (s *Script) Value() *Value {
+func (s *Script) Value() *cc.Value {
 	return s.v
 }
 
@@ -56,7 +69,7 @@ func (s *Script) Len() uint64 {
 
 // Run a dagger script
 func (s *Script) Execute(ctx context.Context, fs FS, out *Fillable) (FS, error) {
-	err := s.v.RangeList(func(idx int, v *Value) error {
+	err := s.v.RangeList(func(idx int, v *cc.Value) error {
 		// If op not concrete, interrupt without error.
 		// This allows gradual resolution:
 		//    compute what you can compute.. leave the rest incomplete.
@@ -89,7 +102,7 @@ func (s *Script) Execute(ctx context.Context, fs FS, out *Fillable) (FS, error)
 }
 
 func (s *Script) Walk(ctx context.Context, fn func(op *Op) error) error {
-	return s.v.RangeList(func(idx int, v *Value) error {
+	return s.v.RangeList(func(idx int, v *cc.Value) error {
 		op, err := newOp(v)
 		if err != nil {
 			return errors.Wrapf(err, "validate op %d/%d", idx+1, s.v.Len())
diff --git a/dagger/script_test.go b/dagger/script_test.go
index b6abf3cb..a59a545a 100644
--- a/dagger/script_test.go
+++ b/dagger/script_test.go
@@ -3,13 +3,14 @@ package dagger
 import (
 	"context"
 	"testing"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 // Test that a script with missing fields DOES NOT cause an error
 // NOTE: this behavior may change in the future.
 func TestScriptMissingFields(t *testing.T) {
-	cc := &Compiler{}
-	s, err := cc.CompileScript("test.cue", `
+	s, err := CompileScript("test.cue", `
 		[
 			{
 				do: "fetch-container"
@@ -18,7 +19,7 @@ func TestScriptMissingFields(t *testing.T) {
 		]
 	`)
 	if err != nil {
-		t.Fatalf("err=%v\nval=%v\n", err, s.v.val)
+		t.Fatalf("err=%v\nval=%v\n", err, s.Value().Cue())
 	}
 }
 
@@ -78,7 +79,6 @@ func TestScriptLoadComponent(t *testing.T) {
 
 // Test that default values in spec are applied
 func TestScriptDefaults(t *testing.T) {
-	cc := &Compiler{}
 	v, err := cc.Compile("", `
 	[
     {
@@ -117,12 +117,11 @@ func TestScriptDefaults(t *testing.T) {
 }
 
 func TestValidateEmptyValue(t *testing.T) {
-	cc := &Compiler{}
 	v, err := cc.Compile("", "#dagger: compute: _")
 	if err != nil {
 		t.Fatal(err)
 	}
-	if err := v.Get("#dagger.compute").Validate("#Script"); err != nil {
+	if err := spec.Validate(v.Get("#dagger.compute"), "#Script"); err != nil {
 		t.Fatal(err)
 	}
 }
@@ -130,7 +129,6 @@ func TestValidateEmptyValue(t *testing.T) {
 func TestLocalScript(t *testing.T) {
 	ctx := context.TODO()
 
-	cc := &Compiler{}
 	src := `[{do: "local", dir: "foo"}]`
 	v, err := cc.Compile("", src)
 	if err != nil {
@@ -157,8 +155,7 @@ func TestWalkBiggerScript(t *testing.T) {
 	t.Skip("FIXME")
 
 	ctx := context.TODO()
-	cc := &Compiler{}
-	script, err := cc.CompileScript("boot.cue", `
+	script, err := CompileScript("boot.cue", `
 [
 //	{
 //		do: "load"
@@ -227,8 +224,7 @@ func TestWalkBiggerScript(t *testing.T) {
 // Compile a script and check that it has the correct
 // number of operations.
 func mkScript(t *testing.T, nOps int, src string) *Script {
-	cc := &Compiler{}
-	s, err := cc.CompileScript("test.cue", src)
+	s, err := CompileScript("test.cue", src)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/dagger/spec.go b/dagger/spec.go
index bac6a835..ab700b23 100644
--- a/dagger/spec.go
+++ b/dagger/spec.go
@@ -3,25 +3,35 @@ package dagger
 import (
 	cueerrors "cuelang.org/go/cue/errors"
 	"github.com/pkg/errors"
+
+	"dagger.cloud/go/dagger/cc"
+)
+
+var (
+	// Global shared dagger spec, generated from spec.cue
+	spec = NewSpec()
 )
 
 // Cue spec validator
 type Spec struct {
-	root *Value
+	root *cc.Value
 }
 
-func newSpec(v *Value) (*Spec, error) {
-	// Spec contents must be a struct
+func NewSpec() *Spec {
+	v, err := cc.Compile("spec.cue", DaggerSpec)
+	if err != nil {
+		panic(err)
+	}
 	if _, err := v.Struct(); err != nil {
-		return nil, err
+		panic(err)
 	}
 	return &Spec{
 		root: v,
-	}, nil
+	}
 }
 
 // eg. Validate(op, "#Op")
-func (s Spec) Validate(v *Value, defpath string) error {
+func (s Spec) Validate(v *cc.Value, defpath string) error {
 	// Lookup def by name, eg. "#Script" or "#Copy"
 	// See dagger/spec.cue
 	def := s.root.Get(defpath)
@@ -32,10 +42,10 @@ func (s Spec) Validate(v *Value, defpath string) error {
 	return nil
 }
 
-func (s Spec) Match(v *Value, defpath string) bool {
+func (s Spec) Match(v *cc.Value, defpath string) bool {
 	return s.Validate(v, defpath) == nil
 }
 
-func (s Spec) Get(target string) *Value {
+func (s Spec) Get(target string) *cc.Value {
 	return s.root.Get(target)
 }
diff --git a/dagger/spec_test.go b/dagger/spec_test.go
index eff49ea1..d94e1d5e 100644
--- a/dagger/spec_test.go
+++ b/dagger/spec_test.go
@@ -2,6 +2,8 @@ package dagger
 
 import (
 	"testing"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 func TestMatch(t *testing.T) {
@@ -25,10 +27,9 @@ func TestMatch(t *testing.T) {
 
 // Test an example op for false positives and negatives
 func testMatch(t *testing.T, src interface{}, def string) {
-	cc := &Compiler{}
-	op := compile(t, cc, src)
+	op := compile(t, src)
 	if def != "" {
-		if err := op.Validate(def); err != nil {
+		if err := spec.Validate(op, def); err != nil {
 			t.Errorf("false negative: %s: %q: %s", def, src, err)
 		}
 	}
@@ -43,13 +44,13 @@ func testMatch(t *testing.T, src interface{}, def string) {
 		if cmpDef == def {
 			continue
 		}
-		if err := op.Validate(cmpDef); err == nil {
+		if err := spec.Validate(op, cmpDef); err == nil {
 			t.Errorf("false positive: %s: %q", cmpDef, src)
 		}
 	}
 }
 
-func compile(t *testing.T, cc *Compiler, src interface{}) *Value {
+func compile(t *testing.T, src interface{}) *cc.Value {
 	v, err := cc.Compile("", src)
 	if err != nil {
 		t.Fatal(err)
diff --git a/dagger/types.go b/dagger/types.go
index 70ecbb68..e0340e37 100644
--- a/dagger/types.go
+++ b/dagger/types.go
@@ -6,6 +6,8 @@ import (
 	"os"
 
 	cueflow "cuelang.org/go/tools/flow"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 var ErrNotExist = os.ErrNotExist
@@ -16,7 +18,7 @@ type Executable interface {
 	Walk(context.Context, func(*Op) error) error
 }
 
-func newExecutable(v *Value) (Executable, error) {
+func newExecutable(v *cc.Value) (Executable, error) {
 	// NOTE: here we need full spec validation,
 	//   so we call NewScript, NewComponent, NewOp.
 	if script, err := NewScript(v); err == nil {
diff --git a/dagger/utils.go b/dagger/utils.go
index cda26e20..211516c8 100644
--- a/dagger/utils.go
+++ b/dagger/utils.go
@@ -3,19 +3,8 @@ package dagger
 import (
 	"crypto/rand"
 	"fmt"
-
-	"cuelang.org/go/cue"
-	cueerrors "cuelang.org/go/cue/errors"
-	"github.com/pkg/errors"
 )
 
-func cueErr(err error) error {
-	if err == nil {
-		return nil
-	}
-	return errors.New(cueerrors.Details(err, &cueerrors.Config{}))
-}
-
 func randomID(size int) (string, error) {
 	b := make([]byte, size)
 	_, err := rand.Read(b)
@@ -24,20 +13,3 @@ func randomID(size int) (string, error) {
 	}
 	return fmt.Sprintf("%x", b), nil
 }
-
-func cueStringsToCuePath(parts ...string) cue.Path {
-	selectors := make([]cue.Selector, 0, len(parts))
-	for _, part := range parts {
-		selectors = append(selectors, cue.Str(part))
-	}
-	return cue.MakePath(selectors...)
-}
-
-func cuePathToStrings(p cue.Path) []string {
-	selectors := p.Selectors()
-	out := make([]string, len(selectors))
-	for i, sel := range selectors {
-		out[i] = sel.String()
-	}
-	return out
-}
diff --git a/dagger/value_test.go b/dagger/value_test.go
index 2217cb04..52b67986 100644
--- a/dagger/value_test.go
+++ b/dagger/value_test.go
@@ -2,10 +2,11 @@ package dagger
 
 import (
 	"testing"
+
+	"dagger.cloud/go/dagger/cc"
 )
 
 func TestValueFinalize(t *testing.T) {
-	cc := &Compiler{}
 	root, err := cc.Compile("test.cue",
 		`
 	#FetchContainer: {
@@ -59,7 +60,6 @@ func TestValueFinalize(t *testing.T) {
 
 // Test that a non-existing field is detected correctly
 func TestFieldNotExist(t *testing.T) {
-	cc := &Compiler{}
 	root, err := cc.Compile("test.cue", `foo: "bar"`)
 	if err != nil {
 		t.Fatal(err)
@@ -76,7 +76,6 @@ func TestFieldNotExist(t *testing.T) {
 
 // Test that a non-existing definition is detected correctly
 func TestDefNotExist(t *testing.T) {
-	cc := &Compiler{}
 	root, err := cc.Compile("test.cue", `foo: #bla: "bar"`)
 	if err != nil {
 		t.Fatal(err)
@@ -92,7 +91,6 @@ func TestDefNotExist(t *testing.T) {
 }
 
 func TestSimple(t *testing.T) {
-	cc := &Compiler{}
 	_, err := cc.EmptyStruct()
 	if err != nil {
 		t.Fatal(err)
@@ -100,7 +98,6 @@ func TestSimple(t *testing.T) {
 }
 
 func TestJSON(t *testing.T) {
-	cc := &Compiler{}
 	v, err := cc.Compile("", `foo: hello: "world"`)
 	if err != nil {
 		t.Fatal(err)
@@ -117,8 +114,7 @@ func TestJSON(t *testing.T) {
 }
 
 func TestCompileSimpleScript(t *testing.T) {
-	cc := &Compiler{}
-	_, err := cc.CompileScript("simple.cue", `[{do: "local", dir: "."}]`)
+	_, err := CompileScript("simple.cue", `[{do: "local", dir: "."}]`)
 	if err != nil {
 		t.Fatal(err)
 	}