Big Tech and product companies, senior. 31 questions across 7 blocks, about 16 hr of work.
The defining feature is calibration rather than difficulty. Every interviewer works from the same rubric and writes evidence-based feedback, so the panel is trying to place you at a level rather than decide whether you can do the job. That means the coding round is genuinely algorithmic and time-boxed, the design round widens in scope as the level rises, and a strong answer with no stated trade-offs scores worse than a middling answer that names what it gave up.
Front-load breadth, put the two hardest rounds mid-week when you still have time to react to a bad session, and keep the last evening for a timed loop and your stories. Two hours a night done every night beats one eight-hour Saturday, because retrieval improves with spacing and a single long session mostly produces the feeling of having worked.
Read the sheets for the core sections of this track at speed. Mark the items you could not answer; they become your revision list all week.
Two passes over the array do it: a left-to-right pass writes the product of everything before each index into the output, then a right-to-left pass multiplies in a running product of everything after it. Linear time, no working array beyond the output, and it is unbothered by zeros.
Evaluate architectural trade-offs in API & Contract Design between consistency, throughput, operational complexity, and data durability at scale.
Evaluate architectural trade-offs in Introduction & Career Narrative between consistency, throughput, operational complexity, and data durability at scale.
The stack and concept questions this loop opens with. Answer before reading, and note which probes you missed rather than whether you got it right.
The quadratic dynamic programme asks for the best chain ending at each index. The faster version keeps one array where slot j holds the smallest possible tail of an increasing subsequence of length j plus one; that array stays sorted, so each element is placed by binary search for O of n log n.
Pick a write policy that matches your consistency requirement rather than treating invalidation as an afterthought, then defend against the three failure modes that only appear under load: stampede on expiry, staleness from lost invalidation messages, and unbounded growth from missing eviction.
State a policy per field: confined, immutable, or guarded by a named lock. Make the state that readers see immutable and swap it atomically; give each independent invariant its own lock. Method-level synchronisation fails because atomic operations do not compose into atomic sequences.
An order book is price levels in price order, each holding a time-ordered queue of orders, plus an ID index so a cancel is O(1); the hard parts are that cancels dominate the flow, the feed must be gap-checked and recoverable, and replay must be deterministic and allocation-free.
Span is a stack-only view over memory you already have, so slicing it costs nothing while Substring allocates a new string and copies. It removes allocations rather than making them faster, which is the right lever in a runtime where the cost is collection pressure rather than the allocation itself.
Whiteboard each one for real, on paper, before you look. A design answer you have only read is one you cannot produce under questioning.
Architect a fault-tolerant Arrays & Strings solution supporting rolling updates, automated failovers, and graceful degradation during network splits.
Architect a fault-tolerant API & Contract Design solution supporting rolling updates, automated failovers, and graceful degradation during network splits.
Architect a fault-tolerant Introduction & Career Narrative solution supporting rolling updates, automated failovers, and graceful degradation during network splits.
The bound is the design, not a detail: it is what applies backpressure to the producer instead of letting an unbounded queue absorb an overload until the process dies. Deciding what a full buffer does to the producer - block, drop, or reject - is the decision that determines how the system fails.
The rounds where there is no correct answer, only a defensible one. State your assumptions out loud; that is what is being scored.
Diagnose performance degradation in Arrays & Strings by isolating thread contention, I/O bottlenecks, and resource limits before attempting code fixes.
Diagnose performance degradation in API & Contract Design by isolating thread contention, I/O bottlenecks, and resource limits before attempting code fixes.
Diagnose performance degradation in Introduction & Career Narrative by isolating thread contention, I/O bottlenecks, and resource limits before attempting code fixes.
Architect a fault-tolerant Compilers & Runtimes solution supporting rolling updates, automated failovers, and graceful degradation during network splits.
Architect a fault-tolerant Behavioural Patterns solution supporting rolling updates, automated failovers, and graceful degradation during network splits.
Return to whatever went worst this week. One session on a genuine weakness is worth three on material you already have.
Architect a fault-tolerant Recursion & Backtracking solution supporting rolling updates, automated failovers, and graceful degradation during network splits.
Model resources around client workflows, paginate with an opaque keyset cursor because offset pagination skips and duplicates rows under concurrent writes, make unsafe operations replayable with a client-supplied idempotency key, and evolve additively so that versioning stays a last resort rather than a routine.
Architect a fault-tolerant Conflict & Collaboration solution supporting rolling updates, automated failovers, and graceful degradation during network splits.
Scope it in the first five minutes to one deterministic flow of park, unpark and charge, model Vehicle, Slot, Level, Ticket and a ParkingLot facade, then push slot allocation and pricing behind strategy interfaces so the variants asked at review time are configuration rather than surgery.
Run the rounds back to back with a timer and no notes. The point is stamina and switching cost, which no amount of single-question practice reveals.
Diagnose performance degradation in Recursion & Backtracking by isolating thread contention, I/O bottlenecks, and resource limits before attempting code fixes.
Accept the request, return 202 with the location of an operation resource, and do the work behind a queue. Clients poll that resource or receive a signed callback, and either way the operation id is the contract - one that a callback can reach before the submitter has finished recording it.
Diagnose performance degradation in Conflict & Collaboration by isolating thread contention, I/O bottlenecks, and resource limits before attempting code fixes.
Diagnose performance degradation in Compilers & Runtimes by isolating thread contention, I/O bottlenecks, and resource limits before attempting code fixes.
Diagnose performance degradation in Behavioural Patterns by isolating thread contention, I/O bottlenecks, and resource limits before attempting code fixes.
Build it from the nearest native element so role, focusability and key handling come free, decide the keyboard model before the visuals, move and restore focus deliberately, and add ARIA only for state the markup cannot express - it changes what assistive technology announces but adds no behaviour.
Write your stories in full, prepare the questions you will ask them, and stop early.
Answer with the reasoning behind three or four choices rather than a chronology of employers, spend most of the time on the two most recent roles, and give a reason for each move that a manager would find rational rather than a reason that flatters you.
Declare it, take the incident commander role explicitly, and mitigate before you diagnose - roll back or shed load first, understand later. Keep one channel as the record, publish updates on a fixed cadence, hand over rather than push through, and let the review produce owned actions instead of narrative.
Trace one real unit of work end to end, read the operational artefacts rather than the marketing ones, interview the people who handle exceptions, and publish a glossary inviting correction. Understanding shows as prediction and knowing why a rule exists; fluency only names things.
One-to-ones are the engineer's time for the things that do not fit anywhere else, not a status meeting. Feedback lands when it is specific, close to the event, about behaviour and its effect, and carries a request. Growth is owned by the engineer; the manager owns opportunity, honest signal and air cover.
Scope is the union of the track's sections, the rounds this employer type asks regardless of role, and the industry if you named one. Weights above 1.0 pull a section up the order; below 1.0 push it down. Nothing is excluded - a deprioritised section still appears when its best question is the most relevant thing left.