diff --git a/settings.gradle.kts b/settings.gradle.kts
index f760dd2..f48e32c 100644
--- a/settings.gradle.kts
+++ b/settings.gradle.kts
@@ -34,8 +34,9 @@ dependencyResolutionManagement {
         mavenCentral()
         maven {
             // https://maven.pkg.github.com/MercuryTechnologies/sqkon/com/mercury/sqkon/library/1.0.0-alpha01/library-1.0.0-alpha01.pom
-            val gprUser = extra["gpr.user"] as String?
-            val gprKey = extra["gpr.key"] as String?
+
+            val gprUser = if (extra.has("gpr.user")) extra["gpr.user"] as String? else null
+            val gprKey = if (extra.has("gpr.key")) extra["gpr.key"] as String? else null
             name = "GitHubPackages"
             url = uri("https://maven.pkg.github.com/MercuryTechnologies/sqkon")
             credentials {