Notes from the classroom

Six months ago we ripped out 14 REST endpoints. Here's the type-safety dividend, the cold-start gotcha, and the migration plan that didn't break a single learner login.

If you can grok dot products, you can grok embeddings. Build a movie-recommender from scratch in 60 lines — no PyTorch, no TensorFlow, no jargon.

We surveyed our recruiter network. The result is uncomfortable: most learners spend their portfolio time on the wrong things. Here's what to swap in.

Most senior-level system-design interviews don't require Kafka, Redis Streams, or Cassandra. Two well-shaped Postgres tables get you 80% of the way there.

After reviewing 5,000+ resumes from our cohorts, the pattern is clear. Most candidates are fighting their template. Here is the layout that wins consistently.

Practical patterns we use in production to keep LLM costs under 4% of revenue: caching, model routing, evals, and the one habit nobody talks about.