[www-apps/gitea] actually its a release build so this should work fine

www-apps/gitea/gitea-1.12.0_rc1.ebuild

@@ -32,7 +32,7 @@ SLOT="0"
 IUSE="+acct pam sqlite"
 
 BDEPEND="dev-lang/go
-	>=net-libs/nodejs-10[npm]"
+	build-client? ( >=net-libs/nodejs-10[npm] )"
 DEPEND="pam? ( sys-libs/pam )"
 RDEPEND="${DEPEND}
 	acct? (
@@ -95,7 +95,11 @@ src_prepare() {
 }
 
 src_compile() {
-	gitea_make build
+	if use build-client ; then
+		gitea_make build
+	else
+		gitea_make backend
+	fi
 }
 
 src_test() {

www-apps/gitea/metadata.xml

@@ -14,5 +14,6 @@
 	</upstream>
 	<use>
 		<flag name="acct">User and group management via acct-*/git packages</flag>
+		<flag name="build-client">Build the client code, instead of using a precompiled one</flag>
 	</use>
 </pkgmetadata>