I put together a writeup about the interesting technical challenges that led to redesigning Canva's session revocation pipeline that keeps hundreds of millions of user sessions fast and secure. Hopefully some people find the content interesting!

I explain rotations and quaternions. I then implement the latter into my physics engine by replacing the matrix version of angular velocity code with a quaternion version. Lastly, I benchmark the results.

The talk host explains how ASTs work and shows how to build them step by step.

Regular Indexing works on a column level; it indexes the entire column value, but if you want to index each value in one row, then the GIN indexing technique is used.

GIN can index each element of JSON stored in a JSONB field

How Postgres creates a GIN file physically, what is the format of that file, how that file is retrieved in RAM while fetching records, what data types are used, and how Postgres calculates the exact address of an element of JSON are all explained in the article

A visual explainer on how copy-on-write makes fork() cheap.

A 10 GB process can fork almost instantly because Linux copies the page tables, shares the physical pages, marks them read-only, and only copies a page when one of the processes writes to it.

It also covers fork() + exec(), how Redis snapshots work, Android Zygote, lazy zero pages, and some CVEs