diff --git a/internal/app/seal_linux.go b/internal/app/seal_linux.go
index 1b36317..9572e9f 100644
--- a/internal/app/seal_linux.go
+++ b/internal/app/seal_linux.go
@@ -20,7 +20,6 @@ import (
 
 	"hakurei.app/container"
 	"hakurei.app/hst"
-	"hakurei.app/internal"
 	"hakurei.app/internal/app/state"
 	"hakurei.app/internal/hlog"
 	"hakurei.app/internal/sys"
@@ -187,7 +186,7 @@ func (seal *outcome) finalise(ctx context.Context, sys sys.State, config *hst.Co
 	if seal.user.username == "" {
 		seal.user.username = "chronos"
 	} else if !posixUsername.MatchString(seal.user.username) ||
-		len(seal.user.username) >= internal.Sysconf(internal.SC_LOGIN_NAME_MAX) {
+		len(seal.user.username) >= sysconf(_SC_LOGIN_NAME_MAX) {
 		return hlog.WrapErr(ErrName,
 			fmt.Sprintf("invalid user name %q", seal.user.username))
 	}
diff --git a/internal/app/sysconf.go b/internal/app/sysconf.go
new file mode 100644
index 0000000..4c5714a
--- /dev/null
+++ b/internal/app/sysconf.go
@@ -0,0 +1,8 @@
+package app
+
+//#include <unistd.h>
+import "C"
+
+const _SC_LOGIN_NAME_MAX = C._SC_LOGIN_NAME_MAX
+
+func sysconf(name C.int) int { return int(C.sysconf(name)) }
diff --git a/internal/sysconf.go b/internal/sysconf.go
deleted file mode 100644
index 712dce7..0000000
--- a/internal/sysconf.go
+++ /dev/null
@@ -1,8 +0,0 @@
-package internal
-
-//#include <unistd.h>
-import "C"
-
-const SC_LOGIN_NAME_MAX = C._SC_LOGIN_NAME_MAX
-
-func Sysconf(name C.int) int { return int(C.sysconf(name)) }