diff --git a/platformio/home/rpc/handlers/project.py b/platformio/home/rpc/handlers/project.py
index 097f7e45..f7a9b8f8 100644
--- a/platformio/home/rpc/handlers/project.py
+++ b/platformio/home/rpc/handlers/project.py
@@ -32,6 +32,10 @@ from platformio.project.helpers import is_platformio_project
 
 
 class ProjectRPC(object):
+    @staticmethod
+    def config_call(path, method, *args):
+        return getattr(ProjectConfig(path), method)(*args)
+
     @staticmethod
     def _get_projects(project_dirs=None):
         def _get_project_data():
diff --git a/platformio/project/config.py b/platformio/project/config.py
index d0abf25c..988b53c2 100644
--- a/platformio/project/config.py
+++ b/platformio/project/config.py
@@ -409,11 +409,11 @@ class ProjectConfig(ProjectConfigBase, ProjectConfigDirsMixin):
     def __repr__(self):
         return "<ProjectConfig %s>" % (self.path or "in-memory")
 
+    def as_dict(self):
+        return {s: self.items(s, as_dict=True) for s in self.sections()}
+
     def to_json(self):
-        result = {}
-        for section in self.sections():
-            result[section] = self.items(section, as_dict=True)
-        return json.dumps(result)
+        return json.dumps(self.as_dict())
 
     def save(self, path=None):
         path = path or self.path