Frontend Engineering

⏱ 3 min read “Build a custom select” is a frontend machine-coding question that looks simple and is genuinely hard. The native <select> element […] Read article

⏱ 3 min read “Design Discord” is a senior+ frontend system-design prompt that combines real-time messaging, voice/video, presence at scale, and a large client-side Read article

⏱ 3 min read “Build a spreadsheet” is one of the harder senior-frontend interview prompts because it combines a non-trivial data model, a virtualized Read article

⏱ 3 min read What separates a static web app from a “live” one is rarely a single feature; it is a collection of Read article

⏱ 3 min read “Build a code editor” is the meta-version of the rich-text-editor question — the same content-editable challenges plus syntax-aware features (highlighting, Read article

⏱ 3 min read “Build a notification inbox” is a frontend interview prompt that overlaps with comments, message threads, and feeds — but with Read article

⏱ 3 min read “Design YouTube’s watch page” is a senior+ frontend system-design prompt that tests how you decompose a heavy, multi-component page. Player, Read article

⏱ 3 min read “Build a filter sidebar” is a frontend machine-coding question that comes up in e-commerce (Amazon), SaaS dashboards (Linear, Jira), and Read article

⏱ 4 min read “Edge computing” went from buzzword to mainstream production by 2025. By 2026 every senior frontend engineer is expected to understand Read article

⏱ 3 min read “Build a comments thread” is one of the most realistic frontend machine-coding problems — every product team builds one eventually. Read article

⏱ 3 min read “Build a tags input” is a frontend machine-coding question that looks easy and rewards careful thinking. The user types, hits Read article

⏱ 3 min read “Design Slack” is a familiar backend system-design prompt. The frontend version is different — Slack’s message thread UI is genuinely Read article

⏱ 3 min read “Build a date range picker” is a frontend machine-coding problem that punishes ambiguity. Used in analytics dashboards, booking flows, and Read article

⏱ 3 min read “Build a rich text editor” is one of the hardest senior-frontend interview prompts. The naive solution — a contenteditable div Read article

⏱ 3 min read “Build a mention input” is a classic frontend machine-coding problem. You type @ and a dropdown of people appears; pick Read article