diff --git a/backend.go b/backend.go
new file mode 100644
index 0000000..a7e97ae
--- /dev/null
+++ b/backend.go
@@ -0,0 +1,8 @@
+package nasin
+
+import "git.tebibyte.media/tomo/x"
+import "git.tebibyte.media/tomo/tomo"
+
+func init () {
+	tomo.Register(1, x.NewBackend)
+}
diff --git a/go.mod b/go.mod
index a7a2814..ac1d064 100644
--- a/go.mod
+++ b/go.mod
@@ -2,6 +2,18 @@ module git.tebibyte.media/fspl/nasin
 
 go 1.20
 
-require git.tebibyte.media/tomo/tomo v0.30.0
+require (
+	git.tebibyte.media/tomo/tomo v0.30.0
+	git.tebibyte.media/tomo/x v0.6.0
+	git.tebibyte.media/tomo/xdg v0.1.0
+)
 
-require golang.org/x/image v0.11.0 // indirect
+require (
+	git.tebibyte.media/tomo/typeset v0.7.0 // indirect
+	git.tebibyte.media/tomo/xgbkb v1.0.1 // indirect
+	github.com/BurntSushi/freetype-go v0.0.0-20160129220410-b763ddbfe298 // indirect
+	github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966 // indirect
+	github.com/jezek/xgb v1.1.0 // indirect
+	github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0 // indirect
+	golang.org/x/image v0.11.0 // indirect
+)
diff --git a/go.sum b/go.sum
index 8deab26..51a5cd6 100644
--- a/go.sum
+++ b/go.sum
@@ -1,5 +1,22 @@
+git.tebibyte.media/sashakoshka/xgbkb v1.0.0/go.mod h1:pNcE6TRO93vHd6q42SdwLSTTj25L0Yzggz7yLe0JV6Q=
 git.tebibyte.media/tomo/tomo v0.30.0 h1:JoTklJ7yFVrzre4AwuKBMwzho9GomC9ySw354wDB4f4=
 git.tebibyte.media/tomo/tomo v0.30.0/go.mod h1:C9EzepS9wjkTJjnZaPBh22YvVPyA4hbBAJVU20Rdmps=
+git.tebibyte.media/tomo/typeset v0.7.0 h1:JFpEuGmN6R2XSCvkINYxpH0AyYUqqs+dZYr6OSd91y0=
+git.tebibyte.media/tomo/typeset v0.7.0/go.mod h1:PwDpSdBF3l/EzoIsa2ME7QffVVajnTHZN6l3MHEGe1g=
+git.tebibyte.media/tomo/x v0.6.0 h1:80BRiSwhZCqu6IPKZoQj7t1puKXXJpMB9eWVHQliTHM=
+git.tebibyte.media/tomo/x v0.6.0/go.mod h1:6INfDGlcPyoYVMem64ScD5AZb43PkXDGkfgaNa5GCqQ=
+git.tebibyte.media/tomo/xdg v0.1.0 h1:6G2WYPPiM2IXleCpKKHuJA34BxumwNWuLsUoX3yu5zA=
+git.tebibyte.media/tomo/xdg v0.1.0/go.mod h1:tuaRwRkyYW7mqlxA7P2+V+e10KzcamNoUzcOgaIYKAY=
+git.tebibyte.media/tomo/xgbkb v1.0.1 h1:b3HDUopjdQp1MZrb5Vpil4bOtk3NnNXtfQW27Blw2kE=
+git.tebibyte.media/tomo/xgbkb v1.0.1/go.mod h1:P5Du0yo5hUsojchW08t+Mds0XPIJXwMi733ZfklzjRw=
+github.com/BurntSushi/freetype-go v0.0.0-20160129220410-b763ddbfe298 h1:1qlsVAQJXZHsaM8b6OLVo6muQUQd4CwkH/D3fnnbHXA=
+github.com/BurntSushi/freetype-go v0.0.0-20160129220410-b763ddbfe298/go.mod h1:D+QujdIlUNfa0igpNMk6UIvlb6C252URs4yupRUV4lQ=
+github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966 h1:lTG4HQym5oPKjL7nGs+csTgiDna685ZXjxijkne828g=
+github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966/go.mod h1:Mid70uvE93zn9wgF92A/r5ixgnvX8Lh68fxp9KQBaI0=
+github.com/jezek/xgb v1.1.0 h1:wnpxJzP1+rkbGclEkmwpVFQWpuE2PUGNUzP8SbfFobk=
+github.com/jezek/xgb v1.1.0/go.mod h1:nrhwO0FX/enq75I7Y7G8iN1ubpSGZEiA3v9e9GyRFlk=
+github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0 h1:Pf/0BAbppEOq4azPH6fnvUX2dycAwZdGkdxFn25j44c=
+github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0/go.mod h1:AHecLyFNy6AN9f/+0AH/h1MI7X1+JL5bmCz4XlVZk7Y=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
diff --git a/path-unix.go b/path-unix.go
new file mode 100644
index 0000000..a93be6a
--- /dev/null
+++ b/path-unix.go
@@ -0,0 +1,16 @@
+//go:build unix && !darwin
+package nasin
+
+import "git.tebibyte.media/tomo/xdg/basedir"
+
+func userDataDir () (string, error) {
+	return basedir.DataHome()
+}
+
+func userConfigDir () (string, error) {
+	return basedir.ConfigHome()
+}
+
+func userCacheDir () (string, error) {
+	return basedir.CacheHome()
+}
diff --git a/path.go b/path.go
index 4e4704b..e5b5f41 100644
--- a/path.go
+++ b/path.go
@@ -21,13 +21,15 @@ type FileWriter interface {
 // ApplicationUserDataFS returns an FS that an application can use to store user
 // data files.
 func ApplicationUserDataFS (app ApplicationDescription) (*FS, error) {
-	return appFs(userDataDir, app)
+	dataDir, err := userDataDir()
+	if err != nil { return nil, err }
+	return appFs(dataDir, app)
 }
 
 // ApplicationUserConfigFS returns an FS that an application can use to store
 // user configuration files.
 func ApplicationUserConfigFS (app ApplicationDescription) (*FS, error) {
-	configDir, err := os.UserConfigDir()
+	configDir, err := userConfigDir()
 	if err != nil { return nil, err }
 	return appFs(configDir, app)
 }
@@ -35,7 +37,7 @@ func ApplicationUserConfigFS (app ApplicationDescription) (*FS, error) {
 // ApplicationUserCacheFS returns an FS that an application can use to store
 // user cache files.
 func ApplicationUserCacheFS (app ApplicationDescription) (*FS, error) {
-	cacheDir, err := os.UserCacheDir()
+	cacheDir, err := userCacheDir()
 	if err != nil { return nil, err }
 	return appFs(cacheDir, app)
 }
@@ -50,14 +52,14 @@ func pathErr (op, path string, err error) error {
 
 func appFs (root string, app ApplicationDescription) (*FS, error) {
 	// remove slashes
-	appname := app.String()
-	appname = strings.ReplaceAll(appname, "/", "-")
-	appname = strings.ReplaceAll(appname, "\\", "-")
+	appid := app.ID
+	appid = strings.ReplaceAll(appid, "/", "-")
+	appid = strings.ReplaceAll(appid, "\\", "-")
 
-	path := filepath.Join(root, appname)
+	path := filepath.Join(root, appid)
 
 	// ensure the directory actually exists
-	err := os.MkdirAll(path, 755)
+	err := os.MkdirAll(path, 700)
 	if err != nil { return nil, err }
 
 	return &FS { path: path }, nil