How software is built well, and what engineering judgement is actually about.
An index buys read speed with write speed and disk; add one for the query you run most and remove the ones you never use.
Database questions in engineering and data interviews, and any slow query on a desk.
From B-tree vs B+ tree in Database Systems · Hussein Nasser
Judge a design by how much a reader must understand to change it safely, and prefer deep modules behind small interfaces.
Code review, design discussions, and software engineering interviews that ask what good code is.
From A Philosophy of Software Design · John Ousterhout
Ask what a consensus protocol assumes about crashes and the network; its guarantee is only as strong as those assumptions.
Distributed systems interviews, database replication questions, and any design that claims strong consistency across machines.
From Distributed Systems 6.1: Consensus · Martin Kleppmann (Cambridge)
Design every retryable operation so that doing it twice has the same effect as doing it once; the network will test this for you.
System design interviews, payment and order systems, and any API that a client might retry.
From Build a Robust Payments Service Using Idempotency Keys · Arpit Bhayani
The practices that make shipping frequent are the ones that make it safe, so do not trade one for the other.
Engineering management questions, system design discussions about release process, and any debate that assumes speed costs reliability.
From Accelerate · Nicole Forsgren, Jez Humble and Gene Kim
A long window degrades before it fills; curate and order what goes in rather than relying on size.
Designing any system that feeds documents to a model, and explaining why a model missed something that was in its context.
From Why LLMs Get Dumb (Context Windows Explained) · NetworkChuck
Find the subproblem and the recurrence first; the implementation is mechanical once the structure is clear.
Coding interviews, and any problem whose difficulty is in the decomposition.
From 5 Simple Steps for Solving Dynamic Programming Problems · Reducible
Build the test set before the feature, measure every change against it, and keep a person in the loop where the metric cannot be trusted.
Any AI product discussion, any system design that includes a model, and the question of how you know an AI feature works.
From How to Systematically Set Up LLM Evals · Dave Ebbelaar