diff --git a/schala-repl/src/language.rs b/schala-repl/src/language.rs
index ce2bedd..34af586 100644
--- a/schala-repl/src/language.rs
+++ b/schala-repl/src/language.rs
@@ -170,6 +170,48 @@ pub trait ProgrammingLanguageInterface {
   fn get_doc(&self, _commands: &Vec<&str>) -> Option<String> {
     None
   }
+
+  /* ------- */
+  // new trait methods
+  //
+  //
+
+  fn run_computation(&mut self, _request: ComputationRequest) -> ComputationResponse {
+    ComputationResponse {
+      main_output: Err(format!("Computation pipeline not implemented")),
+      global_output_stats: GlobalOutputStats::default(),
+      debug_responses: vec![],
+    }
+  }
+
+  fn repl_request(&self, repl_request: String) -> String {
+    format!("Repl request not implemented")
+  }
 }
 
+struct ComputationRequest {
+  pub source: String,
+  pub debug_requests: Vec<DebugRequest>,
+}
 
+struct ComputationResponse {
+  pub main_output: Result<String, String>,
+  pub global_output_stats: GlobalOutputStats,
+  pub debug_responses: Vec<DebugResponse>,
+}
+
+struct DebugRequest {
+  kind: String,
+  value: String
+}
+
+struct DebugResponse {
+  kind: String,
+  value: String
+}
+
+#[derive(Default, Debug)]
+struct GlobalOutputStats {
+  total_duration: Option<time::Duration>,
+  stage_durations: Option<Vec<(String, time::Duration)>>
+}
diff --git a/schala-repl/src/repl/mod.rs b/schala-repl/src/repl/mod.rs
index 0647765..6f0aef0 100644
--- a/schala-repl/src/repl/mod.rs
+++ b/schala-repl/src/repl/mod.rs
@@ -103,6 +103,17 @@ impl NewRepl {
   }
 }
 
+
+
+
+/* --------------------------------------------- */
+
+
+
+
+
+
+
 pub struct Repl {
   options: EvalOptions,
   languages: Vec<Box<ProgrammingLanguageInterface>>,