Codegolf next level. 1024 bytes of C, support if/else, while, for over range(), and function definitions. Ofcourse, not full feature Python, but mainly to prove it can parse and execute some simple Python. So no ast and byte code. It’s a recursive descent parser executes code as it reads, and a loop just seeks backwards and reparses the source each iteration, letting the C stack do the recursion. Variables are single letters, so the ASCII value is the symbol table index.

.arpa is a special TLD, its mean is not to be used but more of to support network infra. Example, we know DNS -> IP. But IP can also resolve to DNS, call reverse DNS. But IP has no central storage look up, so to support that reverse DNS is done through a special in-addr.arpa. In this post, we kind of abuse that infra for ipv6, and use some tip. We will leverage a free Hurricane Electric feature with ip6.arpa domain. Catch is we cannot issue HTTPS because. But read on, the trick is cool

When our rival make faster software than us, instead of feeling defensive, Ben put the hack hat on. Don’t even read code, and bring on tooling like strace to fill out why his tool is slow, ended up making it faster and beat the rival. This is the hacker mindset, someone make it faster mean it has room to improve.

Vercel reduce P99 from 215.8ms -> 19.1 ms. Each request needs to look metadata. Originally metadata is cache per path. Seems efficient. They now move to batch paths, group them. But big group cause in-efficient way. They find a balance, and pair with a bloom filter to reduce the metadata look up time.

Who cares? My first re-action. Just took some damn time library, convert, or do 3 divisions yourself and call it a day. But the author is truely want to make this to next level. A daily timestamp [0..86399] can be converted into Hour, Minute and Second – with the latency of only two multiplications (and on some targets even lower!).

What would you do when you have a big table, and you know adding a new index will help, but it would take a day to complete. What ships instead is a 2,000-row mapping table holding the earliest start_date per filter combination: join that first, and minutes become under 100ms.

A fact about PostgreSQL that surprises everyone: every query against a table takes a lock on every index on that table, whether or not the query uses any of them. The lock are very cheap lock, AccessShareLock. But cheap is not free. Where does these lock store? Bad news, only 16 slot in a hared lock table. Contention is real

This truely read like novel. OpenAI tried to execution RubyGems infra. 2,000+ malicious packages between May and June, exploiting RubyDoc.info’s automatic documentation builds for remote code execution, apparently to scrape UK local government data. The packages carried “oai” in their names and the agents identified themselves. RubyGems froze new registrations for four days, whether any API keys were stolen is still unclear.

Anytime we process payment with Stripe, the fee is painful. And it has been putting that on network fee. Turning out Visa is not taking most of that. On a $100 sale the issuer keeps $2.00 for carrying credit and fraud risk, the processor $0.35, and Visa itself $0.15 for routing and netting. What Visa really sells is settlement: $84.3B moved on an average day in 2024, backed by an $11.2B liquidity reserve.

STP is a network layer-2 protocol that builds a loop-free logical topology by blocking redundant links. The point is to route traffic without causing forver loop in cycle. here we go through a super interactive tour to learn that

AF_PACKET, AF_XDP, DPDK and mlx5 Direct Verbs behind one Go API, so changing backend is mostly a different open call. The one worth the read is Direct Verbs: hardware steering lets your app claim specific flows while Linux keeps the interface as usual, and it still hits 148.6 Mpps on 64-byte packets.