diff --git a/cmd/jb/main.go b/cmd/jb/main.go
index 4fc0646..e49103a 100644
--- a/cmd/jb/main.go
+++ b/cmd/jb/main.go
@@ -26,6 +26,7 @@ import (
 	"regexp"
 
 	"github.com/jsonnet-bundler/jsonnet-bundler/pkg"
+	"github.com/jsonnet-bundler/jsonnet-bundler/pkg/jsonnetfile"
 	"github.com/jsonnet-bundler/jsonnet-bundler/spec"
 	"github.com/pkg/errors"
 	"gopkg.in/alecthomas/kingpin.v2"
@@ -218,9 +219,7 @@ func parseGithubDependency(urlString string) *spec.Dependency {
 }
 
 func updateCommand(jsonnetHome string, urls ...*url.URL) int {
-	jsonnetfile := pkg.JsonnetFile
-
-	m, err := pkg.LoadJsonnetfile(jsonnetfile)
+	m, err := pkg.LoadJsonnetfile(jsonnetfile.File)
 	if err != nil {
 		kingpin.Fatalf("failed to load jsonnetfile: %v", err)
 		return 1
@@ -234,7 +233,7 @@ func updateCommand(jsonnetHome string, urls ...*url.URL) int {
 
 	// When updating, the lockfile is explicitly ignored.
 	isLock := false
-	lock, err := pkg.Install(context.TODO(), isLock, jsonnetfile, m, jsonnetHome)
+	lock, err := pkg.Install(context.TODO(), isLock, jsonnetfile.File, m, jsonnetHome)
 	if err != nil {
 		kingpin.Fatalf("failed to install: %v", err)
 		return 3
@@ -247,7 +246,7 @@ func updateCommand(jsonnetHome string, urls ...*url.URL) int {
 	}
 	b = append(b, []byte("\n")...)
 
-	err = ioutil.WriteFile(pkg.JsonnetLockFile, b, 0644)
+	err = ioutil.WriteFile(jsonnetfile.LockFile, b, 0644)
 	if err != nil {
 		kingpin.Fatalf("failed to write lock file: %v", err)
 		return 3
diff --git a/pkg/packages.go b/pkg/packages.go
index a847298..d5afaa7 100644
--- a/pkg/packages.go
+++ b/pkg/packages.go
@@ -24,13 +24,12 @@ import (
 	"path/filepath"
 
 	"github.com/fatih/color"
+	"github.com/jsonnet-bundler/jsonnet-bundler/pkg/jsonnetfile"
 	"github.com/jsonnet-bundler/jsonnet-bundler/spec"
 	"github.com/pkg/errors"
 )
 
 var (
-	JsonnetFile     = "jsonnetfile.json"
-	JsonnetLockFile = "jsonnetfile.lock.json"
 	VersionMismatch = errors.New("multiple colliding versions specified")
 )
 
@@ -161,18 +160,18 @@ func FileExists(path string) (bool, error) {
 }
 
 func ChooseJsonnetFile(dir string) (string, bool, error) {
-	lockfile := path.Join(dir, JsonnetLockFile)
-	jsonnetfile := path.Join(dir, JsonnetFile)
-	filename := lockfile
+	lockfilePath := path.Join(dir, jsonnetfile.LockFile)
+	jsonnetfilePath := path.Join(dir, jsonnetfile.File)
+	filename := lockfilePath
 	isLock := true
 
-	lockExists, err := FileExists(filepath.Join(dir, JsonnetLockFile))
+	lockExists, err := FileExists(filepath.Join(dir, jsonnetfile.LockFile))
 	if err != nil {
 		return "", false, err
 	}
 
 	if !lockExists {
-		filename = jsonnetfile
+		filename = jsonnetfilePath
 		isLock = false
 	}