A deep, long-form explainer of WebPKI that describes how HTTPS depends on certificate authorities, certificate types (DV/OV/EV), and mechanisms like Certificate Transparency, and examines practical problems — expiration, revocation, CA incidents (e.g. Trustico, Entrust), and the difficulty of revoking large numbers of certs — plus mitigation ideas such as tighter CA restrictions, ACME renewal practices, and improved auditing. The post is based on months of research and aims to map the social, technical, and political complexities of the web’s public key infrastructure.

The author attempts to port a Triton Flash Attention kernel to TPUs using JAX and documents why the translation is harder than expected—due to JAX/XLA’s functional model, immutability, loop/fusion semantics, and static-slice requirements. They implement a tiled causal Flash Attention in JAX, run it on Colab TPUs, benchmark it, build a systolic-array emulator, and describe compiler/optimization lessons learned.