diff --git a/src/lib.zig b/src/lib.zig
index 9e30d9db5c7405879d586bbe34e887d08e6d4b09..6cc637d87a2e198846078d4e215a20f9c2b8b00b 100644
--- a/src/lib.zig
+++ b/src/lib.zig
@@ -502,8 +502,8 @@ pub fn opslice(slice: anytype, index: usize) ?std.meta.Child(@TypeOf(slice)) {
     return slice[index];
 }
 
-pub fn assertLog(ok: bool, message: string) void {
-    if (!ok) std.log.err("assertion failure: {s}", .{message});
+pub fn assertLog(ok: bool, comptime message: string, args: anytype) void {
+    if (!ok) std.log.err("assertion failure: " ++ message, args);
     if (!ok) unreachable; // assertion failure
 }