The author benchmarks a custom lexer against Dart's official scanner, only to find that I/O operations are the real bottleneck due to excessive syscalls. By packaging files into tar.gz archives, the author reduces syscall overhead, resulting in a significant speedup in I/O performance.

This article explores an efficient I/O abstraction using io_uring on Linux and kqueue on FreeBSD/macOS. It discusses how to handle non-blocking I/O with a focus on batching requests and callbacks to improve performance. The author provides a minimal TCP echo server example and suggests a flexible interface for managing I/O across an application.