I write things down
before I lose them.
Mostly I write things down so I can find them again later. If any of it helps someone else figure out the same thing, even better. No fixed theme, no schedule, just whatever I'm learning.
What I've been writing.
Building a Thread-Safe Rate Limiter in Java
Two algorithms, one clean design, and the concurrency details that actually matter — from the token bucket all the way to a lock-free version with CAS.
Building a Thread-Safe LRU Cache
A fixed-size cache with O(1) get and put, built from a hash map and a doubly-linked list — then made thread-safe, with the one insight that makes LRU concurrency genuinely tricky: its reads write.
Building a Thread-Safe Job Scheduler
Jobs that run at a scheduled time, ordered by priority, pulled by a pool of workers. A priority queue, a lock, and one genuinely new primitive — the timed wait — with the theory to explain every line.
Hi, I'm Fazal.
I'm a software engineer. I like understanding how things actually work, not just getting them to run. When I finally figure something out, I write it down so it sticks, and I keep those notes here in the open. If they save you an afternoon too, even better.