FreeExam

Technical leadership

A senior frontend engineer interview on leading design systems, migrations, budgets, and people without formal authority.

These prompts are original practice. They are not questions from a named employer or a live hiring loop.

  1. 1.You are the frontend tech lead and want to consolidate three component libraries into one. Before writing code, what should the design doc you circulate lead with?

  2. 2.Your design doc for moving 300 pages to a new rendering framework is 40 pages long. Reviewers skim it and approve without comments. What change is most likely to get real review?

  3. 3.A new engineer on your team asks whether they need a full design doc to swap the date picker on one settings page. The change is easy to undo. What do you tell them?

  4. 4.Teams across the web app use four different approaches to state management. You want to set one direction. What makes it most likely to stick?

  5. 5.You are writing a doc proposing server rendering for the marketing pages. Which section is most often missing and most valuable to reviewers?

  6. 6.Two senior engineers on different teams have each written a competing proposal for shared form validation. As the lead who must land one approach, what do you do?

  7. 7.Your direction doc says new pages should use the shared data fetching layer. Six months later, which signal best shows the direction is working?

  8. 8.You are the staff frontend engineer. Leadership asks for a two-year technical vision for the web platform. What makes such a vision useful rather than shelfware?

  9. 9.In a design review for new design system tokens, an engineer from the payments team says nothing. You know payments has unusual theming needs. What do you do?

  10. 10.In a review, a senior engineer strongly objects to your plan to lazy load dashboard widgets, citing layout shift. You think the concern is manageable. What is the best response?

  11. 11.A design review for the image pipeline has run three sessions. Each one reopens settled points and no decision is made. You are the lead. What do you do?

  12. 12.After a fair design review, the group chose a styling approach you argued against. What do you do?

  13. 13.A junior engineer presents a design for the notification center. Two senior engineers criticize it harshly and the junior goes silent. You are running the review. What do you do?

  14. 14.Next week you will present a design to replace the app's router. Which preparation most improves the review?

  15. 15.In your review of the checkout page design, a backend lead says the frontend should not own the API aggregation layer at all. That would only affect a later phase. What do you do?

  16. 16.A reviewer leaves a single comment on your design doc: "This feels too complex." What is the best response?

  17. 17.Three weeks after a design review, no one can recall why the team picked the edge caching approach for the storefront. Which practice would have prevented this?

  18. 18.You must choose between two charting libraries for the analytics product. Neither has been tested at your data sizes, and the team needs an answer this sprint. What do you do?

  19. 19.Last quarter you chose a micro-frontend split for the admin console. Which event should most clearly trigger revisiting that decision?

  20. 20.Your team cannot tell whether a new bundler will cut build times by 10 percent or 50 percent. The full switch takes a month. What is the best way to decide?

  21. 21.As the frontend lead, which kind of decision deserves the most time and input from others?

  22. 22.You chose a hand-rolled virtualized list over a library, and it now causes scroll bugs on older tablets. A teammate says you should admit it was a mistake. What is the strongest response?

  23. 23.Your manager wants a firm answer on whether the redesign can ship with full keyboard support by quarter end. You are about 60 percent confident. What do you say?

  24. 24.You picked a state library after a quick spike. Two weeks later a teammate finds it leaks memory in long sessions, and an upstream fix is unclear. What do you do first?

  25. 25.Why should a decision record for the new image component list the options you rejected?

  26. 26.You are leading a framework migration across 300 pages owned by eight teams. How should you sequence the first phase?

  27. 27.Halfway through a two-quarter design system project, you see the full set of 60 components will not be done on time. What should you cut first?

  28. 28.A product manager asks your team to add an animated onboarding tour this sprint. It would push back accessibility fixes you committed to for a legal deadline. What do you do?

  29. 29.Your multi-quarter plan to move the web app off a legacy CSS framework shows no visible result to leadership until the very end. What is a better shape for the plan?

  30. 30.A director asks your team to also rebuild the internal admin tool during the checkout redesign. Your team is already at capacity. What is the best response?

  31. 31.You are scoping a new search results page. Design has a full spec with saved filters, sharing, and a map view. Launch is in six weeks. What do you propose?

  32. 32.Your team owns the shared component library. This month five teams each ask for a custom variant of the button. What is the leader's move?

  33. 33.You are estimating a framework migration for planning. You have rough numbers from three pilot pages. Leadership wants one date. What do you give them?

  34. 34.A feature team asks your platform team to build a general drag-and-drop framework for their one kanban board. What is the strongest reply?

  35. 35.An executive asks for dark mode across the whole product within a month as a quick win. Most pages hard-code colors instead of using design tokens. What do you propose?

  36. 36.Product leadership asks why your frontend roadmap includes a quarter of build tooling work. Which framing works best?

  37. 37.You want time to remove old jQuery code that still runs on the account pages. Which argument is most likely to win that time?

  38. 38.Your team keeps a list of 80 tech debt items, and leadership agrees to give 20 percent of time to them. How should you choose what to work on?

  39. 39.A feature team proposes skipping end-to-end tests on a new low-traffic internal settings page to hit a launch date. As the lead, what is the right approach?

  40. 40.Leadership asks whether the web app's slow build is worth fixing. You have no data yet. What do you do first?

  41. 41.You inherit a frontend codebase with heavy debt and steady pressure to ship features. What is the most effective long-term approach?

  42. 42.A business partner asks you to explain "technical debt" before a planning meeting. Which explanation fits best?

  43. 43.To meet a launch, your team hard-coded date and currency formats. Three months on, no one has cleaned it up and a new market launch needs it. What should have happened at the time?

  44. 44.You are consolidating three component libraries. Each library's original team is proud of its work. How do you start?

  45. 45.In a migration across eight teams, two teams have not started after a month. What do you do first?

  46. 46.Your framework migration has reached 90 percent of pages. The last 10 percent are odd, low-traffic pages no team wants. What is the best plan?

  47. 47.What most reduces the cost each team pays to move onto the new component library?

  48. 48.Midway through a migration, a team finds the new data grid cannot handle their frozen columns. What should you, as migration lead, do?

  49. 49.Leadership asks how the migration to the new framework is going. What is the most useful status to give?

  50. 50.You lead a migration from a client-only app to server rendering, mainly for search ranking and first load. A team asks to skip it because their pages are behind login. What do you do?

  51. 51.How do you keep teams from adding new code on the old component library while the migration is underway?

  52. 52.A team says the migration guide is clear but they lack time this quarter. Their pages are on the migration's critical path. What is the best approach?

  53. 53.When is the right time to announce a removal date for the old component library?

  54. 54.You want every team to meet a performance budget for the product pages. What makes the budget hold over time?

  55. 55.You are setting a Largest Contentful Paint (LCP) budget that other teams must meet. How should you choose the number?

  56. 56.A new accessibility check fails the build for a team launching tomorrow. The only failure is low color contrast in a third-party widget. What do you do?

  57. 57.Code reviews on your team catch the same accessibility mistakes week after week. What is the leader's best move?

  58. 58.Pull requests on your team often wait two days for review, and work piles up. What change helps most?

  59. 59.A senior engineer on your team leaves long, nitpicky review comments about style, and others are discouraged. What do you do?

  60. 60.You are setting an accessibility standard all teams must meet. Which target is best?

  61. 61.One team's JavaScript bundle grew 40 percent in a quarter. They say no single change was large. What does this tell you about your tooling?

  62. 62.A feature team wants a higher performance budget for its page because a new hero video pushed it over. You own the budget. What do you do?

  63. 63.Marketing wants a new landing page in two days, built outside the main app with a page builder. It would skip your performance budget checks. What do you do?

  64. 64.Page speed on the home page fell 30 percent over two months. No team owns the page as a whole, and each team points to others. What do you do first?

  65. 65.After the unowned home page speed regression is fixed, what follow-up best prevents the next one?

  66. 66.A bad release takes down the checkout page. You are the incident lead. What is your first priority?

  67. 67.In the review after the checkout outage, a manager asks who approved the pull request that broke it. You are leading the review. How do you respond?

  68. 68.Post-incident reviews on your team produce long action lists that rarely get finished. What should you change?

  69. 69.An engineer you mentor shipped a change that caused an outage and is now afraid to deploy. What do you do?

  70. 70.Marketing added a chat widget script without telling engineering, and it slowed every page by a second. What is the best lasting fix?

  71. 71.A customer, not your team, found a memory leak in the dashboard. In the follow-up review, which question matters most?

  72. 72.During an incident, three engineers are all trying different fixes in production at once. You are the incident lead. What do you do?

  73. 73.Three backend engineers now write UI for the internal tools. Their pages work but often break keyboard navigation. What is the most effective way to help?

  74. 74.A backend engineer on a growth plan with you is writing UI for the first time. They ask you to just tell them how to structure a component's state. The deadline is weeks away. What do you do?

  75. 75.You want to grow a mid-level frontend engineer toward senior. Which assignment helps most?

  76. 76.You delegated the image loading project to a senior engineer. You would have chosen a different approach, but theirs is sound. What do you do?

  77. 77.An engineer you delegated a feature to is heading toward a design that will clearly fail under expected load. What do you do?

  78. 78.A backend engineer writing UI keeps putting data fetches inside deeply nested components. Which feedback approach works best?

  79. 79.A mentee asks for feedback on their first design doc. It has a major gap in error handling and several small wording issues. How do you give feedback?

  80. 80.Backend engineers on your team avoid CSS work and leave it to the frontend engineers. What change best spreads the skill?

  81. 81.How do you know your mentoring of a junior engineer is working?

  82. 82.A backend engineer's first UI pull request is 2,000 lines. How do you respond?

  83. 83.Your design system launch is six weeks out. You now see it will slip by about three weeks. When should you tell stakeholders?

  84. 84.Two weeks before the redesign launch, a key engineer goes on unexpected leave. What do you do first?

  85. 85.Your weekly status shows green for the migration, but privately you expect a slip. Why does this matter?

  86. 86.Your project is slipping because a partner team's API is late. What is the best action?

  87. 87.Your accessibility remediation is behind. Product suggests dropping screen reader testing to save time. What do you say?

  88. 88.Halfway through the quarter, the team is behind on the framework migration. A teammate proposes a weekend push to catch up. What do you do?

  89. 89.You have told stakeholders the checkout redesign will slip by two weeks. What else should the message include?

  90. 90.Design wants custom, pixel-perfect components for each product area. You want one consistent design system. How do you make progress?

  91. 91.A feature team keeps building its own modal instead of using the shared one. What do you do first?

  92. 92.You learn the feature team bypassed the shared modal because it could not trap focus inside nested menus. What do you do next?

  93. 93.Product and design disagree about whether the new dashboard should load fast with less data or slower with all of it. Your team is caught in between. What is the best move?

  94. 94.Design hands over a new component spec with no states for loading, errors, or empty data. What do you do?

  95. 95.Your design system team is booked this quarter. A product team needs a date picker now and the library has none. What do you do?

  96. 96.A designer and an engineer on your team keep clashing over spacing details in reviews. Both escalate to you. What do you do?

  97. 97.You want product managers to care about the design system. Which argument is most likely to land?

  98. 98.Your manager wants to commit to a full rewrite of the frontend this year. You think an incremental migration is safer. What do you do?

  99. 99.A principal engineer proposes a new state library for the whole org. You have data showing it hurts performance for your users on low-end phones. What do you do?

  100. 100.You want other teams to adopt your new error boundary pattern, but you have no authority over them. What works best?

  101. 101.Your manager decides to ship the redesign without the keyboard fixes. You believe this creates legal risk. What do you do?

  102. 102.Another team's lead dismisses your proposal for a shared build config in a meeting. What is a good next step?

  103. 103.A staff engineer plans to move all styling to utility classes and asks for feedback. You disagree. What makes your disagreement most useful?

  104. 104.Every design decision on the web team goes through you, and the team waits days for your input. What should you change?

  105. 105.You notice you are the only person who can debug the frontend build pipeline. What should you do?

  106. 106.You are the only approver for changes to the shared component library, and review times keep growing. What do you do?

  107. 107.You often fix teammates' bugs yourself because it is faster. Over time, what is the main risk?

  108. 108.You will be on leave for a month in the middle of the framework migration. What best prepares the team?

  109. 109.A senior engineer on your team keeps asking you to approve small technical choices in their own area. What do you say?