diff --git a/nssa/core/src/program.rs b/nssa/core/src/program.rs
index 82023f3..a96d3cf 100644
--- a/nssa/core/src/program.rs
+++ b/nssa/core/src/program.rs
@@ -12,11 +12,20 @@ pub struct ProgramInput<T> {
     pub instruction: T,
 }
 
+#[derive(Serialize, Deserialize, Clone)]
+#[cfg_attr(any(feature = "host", test), derive(Debug, PartialEq, Eq))]
+pub struct ChainedCall {
+    pub program_id: ProgramId,
+    pub instruction_data: InstructionData,
+    pub account_indices: Vec<usize>,
+}
+
 #[derive(Serialize, Deserialize, Clone)]
 #[cfg_attr(any(feature = "host", test), derive(Debug, PartialEq, Eq))]
 pub struct ProgramOutput {
     pub pre_states: Vec<AccountWithMetadata>,
     pub post_states: Vec<Account>,
+    pub chained_call: Option<ChainedCall>
 }
 
 pub fn read_nssa_inputs<T: DeserializeOwned>() -> ProgramInput<T> {
@@ -33,6 +42,7 @@ pub fn write_nssa_outputs(pre_states: Vec<AccountWithMetadata>, post_states: Vec
     let output = ProgramOutput {
         pre_states,
         post_states,
+        chained_call: None
     };
     env::commit(&output);
 }
diff --git a/nssa/program_methods/guest/src/bin/privacy_preserving_circuit.rs b/nssa/program_methods/guest/src/bin/privacy_preserving_circuit.rs
index a1aa8c9..1baa5a0 100644
--- a/nssa/program_methods/guest/src/bin/privacy_preserving_circuit.rs
+++ b/nssa/program_methods/guest/src/bin/privacy_preserving_circuit.rs
@@ -27,6 +27,7 @@ fn main() {
     let ProgramOutput {
         pre_states,
         post_states,
+        chained_call: _,
     } = program_output;
 
     // Check that there are no repeated account ids