diff --git a/cmd/nixfig/main.go b/cmd/nixfig/main.go
deleted file mode 100644
index f36d962..0000000
--- a/cmd/nixfig/main.go
+++ /dev/null
@@ -1,53 +0,0 @@
-package main
-
-import (
-	"encoding/json"
-	"errors"
-	"fmt"
-	"os"
-	"path/filepath"
-
-	"go.jolheiser.com/nixfig"
-)
-
-func maine() error {
-	if len(os.Args) != 2 {
-		return errors.New("nixfig requires 1 argument")
-	}
-	fn := os.Args[1]
-
-	data, err := os.ReadFile(fn)
-	if err != nil {
-		return fmt.Errorf("could not read file %q: %w", fn, err)
-	}
-
-	var out []byte
-	var a any
-	switch ext := filepath.Ext(fn); ext {
-	case ".json":
-		if err := json.Unmarshal(data, &a); err != nil {
-			return fmt.Errorf("invalid JSON file: %w", err)
-		}
-		out, err = nixfig.Marshal(a)
-	case ".nix":
-		if err := nixfig.Unmarshal(data, &a); err != nil {
-			return fmt.Errorf("invalid nix file: %w", err)
-		}
-		out, err = json.Marshal(a)
-	default:
-		return fmt.Errorf("unknown extension %q, must be json or nix", ext)
-	}
-	if err != nil {
-		return err
-	}
-
-	fmt.Print(string(out))
-	return nil
-}
-
-func main() {
-	if err := maine(); err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-}
diff --git a/cmd/nixgen/main.go b/cmd/nixgen/main.go
deleted file mode 100644
index c76bc45..0000000
--- a/cmd/nixgen/main.go
+++ /dev/null
@@ -1,70 +0,0 @@
-package main
-
-import (
-	"encoding/json"
-	"errors"
-	"flag"
-	"fmt"
-	"os"
-	"strings"
-
-	"github.com/pelletier/go-toml/v2"
-	"go.jolheiser.com/nixfig"
-	"gopkg.in/yaml.v3"
-)
-
-func maine() error {
-	fs := flag.NewFlagSet("nixgen", flag.ExitOnError)
-
-	format := func(v any) ([]byte, error) {
-		return json.MarshalIndent(v, "", "\t")
-	}
-	formatFunc := func(s string) error {
-		switch strings.ToLower(s) {
-		case "json":
-			// Default
-		case "yaml":
-			format = yaml.Marshal
-		case "toml":
-			format = toml.Marshal
-		default:
-			return fmt.Errorf("unknown format %q, should be one of [json yaml toml]", s)
-		}
-		return nil
-	}
-	fs.Func("format", "Output format [json, yaml, toml]: default 'json'", formatFunc)
-	fs.Func("f", "--format", formatFunc)
-	if err := fs.Parse(os.Args[1:]); err != nil {
-		return err
-	}
-
-	if len(fs.Args()) < 1 {
-		return errors.New("nixgen requires a file")
-	}
-
-	fp := fs.Arg(0)
-	data, err := os.ReadFile(fp)
-	if err != nil {
-		return err
-	}
-
-	var nix map[string]any
-	if err := nixfig.Unmarshal(data, &nix); err != nil {
-		return err
-	}
-
-	out, err := format(nix)
-	if err != nil {
-		return err
-	}
-	fmt.Println(string(out))
-
-	return nil
-}
-
-func main() {
-	if err := maine(); err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-}
diff --git a/nixfig.go b/nixfig.go
index e1597bc..91a746e 100644
--- a/nixfig.go
+++ b/nixfig.go
@@ -46,7 +46,7 @@ func Unmarshal(data []byte, v any) error {
 	}
 
 	var stdout, stderr bytes.Buffer
-	cmd := exec.Command(Nix, "eval", "--json", "--expr", string(data))
+	cmd := exec.Command(Nix, "--extra-experimental-features", "nix-command", "eval", "--json", "--expr", string(data))
 	cmd.Stdout = &stdout
 	cmd.Stderr = &stderr
 	if err := cmd.Run(); err != nil {
@@ -74,7 +74,7 @@ func Marshal(v any) ([]byte, error) {
 	}
 
 	var stdout, stderr bytes.Buffer
-	cmd := exec.Command(Nix, "eval", "--expr", fmt.Sprintf(`(builtins.fromJSON %q)`, string(data)))
+	cmd := exec.Command(Nix, "--extra-experimental-features", "nix-command", "eval", "--expr", fmt.Sprintf(`(builtins.fromJSON %q)`, string(data)))
 	cmd.Stdout = &stdout
 	cmd.Stderr = &stderr
 	if err := cmd.Run(); err != nil {