The whole product lives or dies on a feedback loop measured in seconds: a swipe is a label, and the next video has to reflect it. The hard part is exploring enough to discover what someone likes without trapping them in a filter bubble or amplifying junk.
Updated Aug 2026 · Grounded in real Forward Deployed Engineer interview loops and written to a senior-engineer editorial bar.
The whole product lives or dies on a feedback loop measured in seconds: a swipe is a label, and the next video has to reflect it. The hard part is exploring enough to discover what someone likes without trapping them in a filter bubble or amplifying junk.
The senior signal is treating exploration versus exploitation as the core tension and watch-completion versus skip as the real label, not likes. Strong candidates design a multi-task ranker (completion, replay, share, follow, plus a skip penalty), build a tight near-real-time feedback loop, and add integrity and diversity guardrails so the optimizer does not amplify clickbait or collapse into a filter bubble. Probe with 'watch time went up but day-30 retention dropped' to test whether they understand short-term-metric gaming and the bored-user failure mode.
No comments yet — be the first to share your approach.
