Vault
Databases & Infrastructure
ACID, One Letter at a Time
How databases actually deliver Atomicity, Consistency, Isolation, and Durability — write-ahead logs, MVCC, locking schedules, and the fsync problem that's embarrassed most storage stacks at least once.
Codd's 1970 Paper, Annotated
Walking through 'A Relational Model of Data for Large Shared Data Banks' — what 'relational' actually means mathematically, which ideas survived into SQL, and which quietly got dropped.
The 'Lo' Crash: The Internet's First Bug Report
Why SRI's computer crashed after Charley Kline typed three letters, what actually broke, and how a buffer overflow in an auto-complete feature became the internet's origin story.
Normal Forms: 1NF → BCNF, With Examples
Codd's design rules for tables — what each anomaly looks like, how the next normal form fixes it, and when to deliberately break the rules for performance.
The Query Optimizer: How SQL Actually Runs
You write what you want; the database decides how. A tour of how an optimizer parses, rewrites, estimates, and plans a SQL query — and why the same query can be fast on Monday and slow on Friday.
The JOIN: Relationships Through Values, Not Pointers
Expressing relationships through shared values instead of physical references was the real breakthrough of the relational model. Fifty years later, the four join types, three join algorithms, and one fundamental question still run most of the world's data.
OAuth: Delegating Trust
The authorization framework that lets you 'Sign in with Google' solved the password-sharing problem and enabled the platform economy.
Cookies: Giving HTTP a Memory
Lou Montulli's small text files solved HTTP's statelessness problem — and accidentally created the infrastructure for login sessions, shopping carts, and the ad-tracking economy.
SSL/TLS: Securing the Web
Netscape needed online shopping to work. That meant encrypting HTTP — so two engineers built the protocol that now protects every connection on the internet.
The Relational Model & SQL: Organizing the World's Data
Edgar Codd's 1970 paper gave us a mathematical foundation for databases, and SQL gave us a language to query them. IBM sat on it. Oracle shipped it first.
ARPANET: The Network That Started It All
A crashed login, a nervous grad student, and an unauthorized email — how a Cold War research project accidentally laid the foundation for the internet.