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Juspay interview process (2026)

Blog / Juspay interview process (2026)

Juspay candidate accounts repeatedly discuss graph problems, Tree of Space and explaining implementation choices. Formats vary by role, cohort and interviewer. This guide connects ten TechPrep exercises to specific reports and keeps historical tasks and related variants visible. It is a preparation guide, not a guaranteed interview schedule.The evidence spans a 2026 SDE-I account, a 2025 off-campus account and a summer-intern report. Some algorithm exercises come from older 2020 and 2023 accounts, labelled below. A page updated in 2026 does not necessarily describe an interview held in 2026.

Screening and problem solving: The batch-2025 report names three functional-graph tasks. A different September 2026 account describes another assessment and says its interviewer skipped DSA because of the candidate’s programming background. Ask your recruiter about the assessment for your specific role.
Tree of Space implementation: The detailed hiring-challenge account specifies ownership-aware lock, unlock and upgrade operations on an m-ary tree. Candidates explain their data structures, invariants and operation costs. The 2026 account links the original challenge and also reports a separate lock-wheel BFS exercise.
Concurrency and technical discussion: The 2024 SDE account describes a follow-up about making the locking logic safe when operations overlap. Expect to explain interleavings, shared state and synchronization choices. Requirements differ, and a sequential solution alone does not establish thread safety.
Projects, fundamentals and decomposition: The 2025 backend-intern account includes HashMap internals and physical-system reasoning. The off-campus account also describes core CS and React discussion. These are role-specific reports, not a mandatory checklist for every candidate.

The collection contains nine algorithm exercises and one sequential design exercise. The roadmap also includes 29 general behavioral prompts. Those behavioral prompts are preparation material, not questions attributed to Juspay.

Graphs and search: Functional-graph scoring, cycle sums, meeting cells and lock-wheel BFS.
Counting, ordering and scheduling: Inversions, score ties, balanced workloads and historical tree/array tasks.
Tree locking and concurrency: Ownership rules, state changes, operation costs and separate concurrency follow-ups.
Projects and design discussion: Explain concrete decisions and clarify incomplete assignment requirements.
Preparation plan: Practise contracts, invariants, counterexamples and communicating trade-offs.

1. Graphs and search

The July 2023 OA report describes incoming-index scoring, cycle-index sums and a meeting-cell problem. Largest Sum Cycle counts only vertices on a cycle. Test a long incoming tail and two cycles whose lengths and sums favor different answers.Nearest Meeting Cell by Total Distance explicitly minimizes the sum of the two shortest distances. The code in that historical report uses this objective. Another nearest-cell report leaves the metric ambiguous. Do not infer a minimum-of-maximum objective from the word “nearest”. State the tie rule before coding.Find the Node with the Highest Edge Score in a Graph is related practice for Maximum Weight Node. The existing exercise chooses the smallest index on ties and gives every node an outgoing edge. The reported variant allows -1 sinks and chooses the highest index on ties. After solving it, explain the two changes needed for that variant.Open the Lock is explicitly linked in the 2026 report. Explain why BFS gives the fewest moves, then test blocked starts, wraparound and unreachable targets.

2. Counting, ordering and scheduling

Count of Inversions corresponds to the inversion-pair task in the off-campus account. Explain why merge-sort counting handles cross-half pairs and how equal values affect the comparison.A linked elimination-round report describes the tasks behind Cumulative Score Winner and Find Minimum Time to Finish All Jobs. For score updates, first determine the final winning total, then resolve the chronological tie among eligible winners. The practice contract explicitly includes signed changes. For job assignment, distinguish a heuristic from an algorithm that guarantees the minimum maximum load. The source itself records a failed greedy case.Validate Binary Search Tree and Merge k Sorted Arrays are explicitly linked in the historical 2020 account. Treat them as older preparation examples. Check inherited BST bounds and discuss the heap size when merging multiple sorted inputs.

3. Tree locking and concurrency

Tree of Space Lock Manager adapts the complete m-ary tree challenge into a deterministic class exercise. Locks exclude locked ancestors and descendants. Unlock requires the owner. Upgrade requires at least one locked descendant, all owned by the caller, and releases those locks before locking the requested ancestor. Failed operations must preserve state.The practice constructor accepts the level-order names as a comma-separated string. This is an input adapter for the exercise. The graded contract is sequential. It does not test concurrent calls or claim that its data structures are thread-safe.Track how many ancestor sets contain a locked node when discussing memory and update costs. A successful upgrade must inspect the relevant locks before changing anything, so a mixed-owner failure cannot partly release the subtree.For the interview follow-up, use the December 2023 discussion as a prompt to reason about overlapping calls. Draw an interleaving between an ancestor and descendant lock. Identify the shared check-and-update sequence and explain how your synchronization strategy protects it. Candidate transcripts include incomplete proposals, so do not treat every posted solution as correct.

4. Projects and design discussion

The September 2026 account describes project authentication, networking and scaling discussion. Be ready to explain your own request flow, cache boundaries and failure handling. Those themes do not establish a standalone payment-gateway or rate-limiter assignment, so this collection does not attribute one.The 2026 SDE-I account describes a parking variant where four motorcycles share a car space. Clarify allocation order, fractional-hour charging and invalid exit behavior before implementing a practice version. The report does not fully define those rules, so it is covered here as a discussion task rather than a graded exercise.The backend-intern report includes mechanical decomposition prompts. Practise naming components, explaining their interaction and checking assumptions aloud. The 2025 off-campus report includes a lighter-egg weighing puzzle, which should not be confused with the floor-based egg-dropping problem.Rainwater puddle formation, JSON parsing and Linux command tasks appear in some reports without enough specification to recreate faithful graded questions. They remain outside this release.

5. Preparation plan

1. Solve the graph and counting exercises, stating the objective and tie rules before implementation. 2. Build the tree lock manager and test mixed owners, repeated calls, upgrades and failure without mutation. 3. Revisit the same design under an overlapping-call scenario and explain what must be synchronized. 4. Walk through one of your own projects, including a failed request and the information you would inspect to debug it. 5. Use the roadmap’s behavioral prompts for concise examples of decisions, feedback and ownership. Keep these general prompts separate from attributed interview questions.

Conclusion

Start with the exact rules of each exercise, then justify the state and invariants your solution maintains. Use the guide’s date and variant notes when interpreting candidate reports. Your recruiter’s current instructions take precedence over any historical account.