diff --git a/.gitignore b/.gitignore
index a5e9bdd..5fd1102 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 __pycache__
+giteapc-config.make
 giteapc-config-*.make
diff --git a/giteapc.make b/giteapc.make
index 6f28424..7e8f23b 100644
--- a/giteapc.make
+++ b/giteapc.make
@@ -1,8 +1,6 @@
 # giteapc: version=1
 
-ifneq ($(GITEAPC_CONFIG),)
-include giteapc-config-$(GITEAPC_CONFIG).make
-endif
+-include giteapc-config.make
 
 configure:
 	@ true
diff --git a/giteapc/repo.py b/giteapc/repo.py
index 61a1b81..5aec961 100644
--- a/giteapc/repo.py
+++ b/giteapc/repo.py
@@ -286,7 +286,8 @@ def build(*args, install=False, skip_configure=False):
 
         env = os.environ.copy()
         if s.config:
-            env["GITEAPC_CONFIG"] = config
+            env["GITEAPC_CONFIG"] = s.config
+            r.set_config(s.config)
         env["GITEAPC_PREFIX"] = PREFIX_FOLDER
 
         if not skip_configure:
diff --git a/giteapc/repos.py b/giteapc/repos.py
index a5f98cd..4c4f1d0 100644
--- a/giteapc/repos.py
+++ b/giteapc/repos.py
@@ -141,6 +141,14 @@ class LocalRepo:
         with ChangeDirectory(self.folder):
             return run(["make", "-f", "giteapc.make", target], env=env)
 
+    def set_config(self, config):
+        source = self.folder + f"/giteapc-config.make"
+        target = self.folder + f"/giteapc-config-{config}.make"
+
+        if os.path.exists(source):
+            os.remove(source)
+        os.symlink(target, source)
+
     # Metadata
 
     def metadata(self):