diff --git a/cmd/hsu/conf.go b/cmd/hsu/conf.go
new file mode 100644
index 00000000..683bdc8a
--- /dev/null
+++ b/cmd/hsu/conf.go
@@ -0,0 +1,7 @@
+//go:build !rosa
+
+package main
+
+// hsuConfPath is an absolute pathname to the hsu configuration file. Its
+// contents are interpreted by parseConfig.
+const hsuConfPath = "/etc/hsurc"
diff --git a/cmd/hsu/config_rosa.go b/cmd/hsu/config_rosa.go
new file mode 100644
index 00000000..30303dba
--- /dev/null
+++ b/cmd/hsu/config_rosa.go
@@ -0,0 +1,7 @@
+//go:build rosa
+
+package main
+
+// hsuConfPath is the pathname to the hsu configuration file, specific to
+// Rosa OS. Its contents are interpreted by parseConfig.
+const hsuConfPath = "/system/etc/hsurc"
diff --git a/cmd/hsu/parse.go b/cmd/hsu/parse.go
index d4f7df43..f9191d9a 100644
--- a/cmd/hsu/parse.go
+++ b/cmd/hsu/parse.go
@@ -84,10 +84,6 @@ func parseConfig(r io.Reader, puid uint32) (userid uint32, ok bool, err error) {
 	return useridEnd + 1, false, s.Err()
 }
 
-// hsuConfPath is an absolute pathname to the hsu configuration file.
-// Its contents are interpreted by parseConfig.
-const hsuConfPath = "/etc/hsurc"
-
 // mustParseConfig calls parseConfig to interpret the contents of hsuConfPath,
 // terminating the program if an error is encountered, the syntax is incorrect,
 // or the current user is not authorised to use hsu because its uid is missing.
diff --git a/internal/rosa/hakurei.go b/internal/rosa/hakurei.go
index e1dabc25..2d09856a 100644
--- a/internal/rosa/hakurei.go
+++ b/internal/rosa/hakurei.go
@@ -66,7 +66,7 @@ mkdir -p /work/system/libexec/hakurei/
 
 echo '# Building hakurei.'
 go generate -v ./...
-go build -trimpath -v -o /work/system/libexec/hakurei -ldflags="-s -w
+go build -trimpath -v -tags=rosa -o /work/system/libexec/hakurei -ldflags="-s -w
 	-buildid=
 	-linkmode external
 	-extldflags=-static