From db7b1d1c39ee1da779a7fd0c5ab70125eabc02b9 Mon Sep 17 00:00:00 2001
From: Haardik H <haardik.haardik@coinbase.com>
Date: Wed, 9 Jul 2025 13:58:30 -0400
Subject: [PATCH] fallback to EL for state root if config AND state root is
 zero from builder

---
 crates/rollup-boost/src/payload.rs | 18 ++++++++++++++++++
 crates/rollup-boost/src/server.rs  |  5 ++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/crates/rollup-boost/src/payload.rs b/crates/rollup-boost/src/payload.rs
index 38027b71..53ee4234 100644
--- a/crates/rollup-boost/src/payload.rs
+++ b/crates/rollup-boost/src/payload.rs
@@ -134,6 +134,24 @@ impl OpExecutionPayloadEnvelope {
             },
         }
     }
+
+    pub fn state_root(&self) -> B256 {
+        match self {
+            OpExecutionPayloadEnvelope::V3(payload) => payload
+                .execution_payload
+                .payload_inner
+                .payload_inner
+                .state_root
+                .into(),
+            OpExecutionPayloadEnvelope::V4(payload) => payload
+                .execution_payload
+                .payload_inner
+                .payload_inner
+                .payload_inner
+                .state_root
+                .into(),
+        }
+    }
 }
 
 impl From<OpExecutionPayloadEnvelope> for ExecutionPayload {
diff --git a/crates/rollup-boost/src/server.rs b/crates/rollup-boost/src/server.rs
index 870808eb..6e2167e4 100644
--- a/crates/rollup-boost/src/server.rs
+++ b/crates/rollup-boost/src/server.rs
@@ -206,7 +206,10 @@ impl RollupBoostServer {
 
             let payload = self.builder_client.get_payload(payload_id, version).await?;
 
-            if self.use_l2_client_for_state_root == false {
+            let should_use_l2_client_for_state_root =
+                self.use_l2_client_for_state_root && payload.state_root() == B256::ZERO;
+
+            if !should_use_l2_client_for_state_root {
                 let _ = self
                     .l2_client
                     .new_payload(NewPayload::from(payload.clone()))