diff --git a/gir.js b/gir.js
index 18c783d..7241402 100644
--- a/gir.js
+++ b/gir.js
@@ -976,8 +976,8 @@ function ircbotRun(program, input, maxCycles = 400000) {
 		// even if there are no indices we can get values that
 		// the rest of the code can work with
 		let memoryIndices = Array.from(result.state.memory.keys());
-		let min = memoryIndices.reduce(Math.min, tapeHead);
-		let max = memoryIndices.reduce(Math.max, tapeHead);
+		let min = memoryIndices.reduce((x,y) => Math.min(x, y), tapeHead);
+		let max = memoryIndices.reduce((x,y) => Math.max(x, y), tapeHead);
 
 		// Get 15 cells of context on each side of tape head
 		// Exception is if max or min comes up before that, in which