diff --git a/perftree-cli/src/bin/perftree.rs b/perftree-cli/src/bin/perftree.rs
index c8b2680..47a41c5 100644
--- a/perftree-cli/src/bin/perftree.rs
+++ b/perftree-cli/src/bin/perftree.rs
@@ -102,6 +102,20 @@ fn main() -> io::Result<()> {
             "exit" | "quit" => {
                 break;
             }
+            "chess960" | "frc" => {
+                if let Some(chess960) = words.next() {
+                    match chess960.parse() {
+                        Ok(chess960) => {
+                            state.set_chess960(chess960)?;
+                        }
+                        Err(e) => {
+                            eprintln!("cannot parse given bool: {}", e);
+                        }
+                    }
+                } else {
+                    eprintln!("missing argument, expected true or false");
+                }
+            }
             other => {
                 eprintln!("unknown command {:?}", other);
             }
diff --git a/perftree/src/lib.rs b/perftree/src/lib.rs
index 44b9eed..6bb2558 100644
--- a/perftree/src/lib.rs
+++ b/perftree/src/lib.rs
@@ -82,6 +82,13 @@ impl State {
                 .perft(&self.fen, &self.moves, self.depth - self.moves.len())?,
         ))
     }
+
+    pub fn set_chess960(&mut self, chess960: bool) -> io::Result<()> {
+        write!(
+            self.stockfish.out,
+            "setoption name UCI_Chess960 value {chess960}\n",
+        )
+    }
 }
 
 #[derive(Debug, Clone)]