diff --git a/source/dub/dependencyresolver.d b/source/dub/dependencyresolver.d
index dcd5f82..aea79ba 100644
--- a/source/dub/dependencyresolver.d
+++ b/source/dub/dependencyresolver.d
@@ -88,7 +88,9 @@
 					package_names[pidx] = basepack;
 				}
 
-				configs = getSpecificConfigs(basepack, ch) ~ configs;
+				foreach (c; getSpecificConfigs(basepack, ch))
+					if (!configs.canFind(c))
+						configs = c ~ configs;
 
 				if (any_config.length <= pidx) any_config.length = pidx+1;
 				any_config[pidx] = configs.length > 0;