Stop forgetting what you learn: spaced repetition for engineers

You solve the problem, you feel smart, you forget it in a week. Here's the learning technique that fixes that, borrowed from language learners and weirdly underused by devs.

Be honest: how many times have you solved a problem, felt genuinely clever, and then drawn a complete blank on it a week later? It's not a you problem. It's how memory works — without reinforcement, knowledge has a brutally short shelf life.

The trick language learners figured out

Spaced repetition is simple: review something right before you're about to forget it, and each successful recall pushes the next “forget point” further out. Review on day 1, then 3, then 7, then 16… The intervals stretch as the memory hardens. Flashcard apps have used this for decades. Engineers mostly don't, and it's a missed trick.

How to actually apply it to code

• After solving something tricky, write a one-line summary of the pattern — not the whole solution, the idea.
• Schedule three resurfaces: in a few days, a couple weeks, a month.
• On each resurface, try to re-derive it before peeking. The struggle is the point.
• Review your own old code, not someone's polished editorial — it's stickier because it's yours.

Your brain is a cache. Everything you learn has a TTL. Spaced repetition just schedules the refresh before the entry expires.

Grinding 300 problems and forgetting 280 isn't learning — it's cardio. Space the reviews and you'll actually keep what you earn.