nCino · Software Engineer
Updated · 2026-10-02

nCino Software Engineer
Interview Guide

THE 60-SECOND BRIEF

As a Software Engineer at nCino, you are at the heart of transforming the global financial services industry. You will be responsible for building, scaling, and maintaining the nCino Bank Operating System, a cloud-based platform that empowers financial institutions to operate more efficiently and provide a superior customer experience. Your work directly impacts how banks manage loan lifecycles, account openings, and compliance, making your technical contributions critical to the stability and success of our clients. The role requires more than just high-level coding proficiency; it demands a deep understanding of Object-Oriented Programming (OOP) and the ability to design robust, scalable systems. You will collaborate closely with product managers, QA engineers, and cross-functional teams to translate complex business requirements into elegant software solutions.

This guide is scoped to a Software Engineer candidate at nCino.

nCino candidates report 3 rounds over 3-5 weeks. The stages below are what candidates describe, not a published process.

OOP (Object-Oriented Programming)Programming Assessments / Coding ChallengesSystem Design / Architecture Design (Whiteboard)

21 min read

Browse Software Engineer questions

See the practice prompts

19Practice promptsAcross five skill areas

As a Software Engineer at nCino, you are at the heart of transforming the global financial services industry. You will be responsible for building, scaling, and maintaining the nCino Bank Operating System, a cloud-based platform that empowers financial institutions to operate more efficiently and provide a superior customer experience. Your work directly impacts how banks manage loan lifecycles, account openings, and compliance, making your technical contributions critical to the stability and success of our clients. The role requires more than just high-level coding proficiency; it demands a deep understanding of Object-Oriented Programming (OOP) and the ability to design robust, scalable systems. You will collaborate closely with product managers, QA engineers, and cross-functional teams to translate complex business requirements into elegant software solutions. Whether you are working on the Salesforce platform, utilizing Apex, or building out front-end components, you are expected to be a proactive problem solver who is vocal about process improvements and committed to delivering high-quality, maintainable code.

01

Recruiter Screening

reported

Initial screening call with a recruiter to discuss background and role fit.

What to demonstrate

  • Initial screening call with a recruiter to discuss background and role fit
  • Depth in OOP (Object-Oriented Programming)

How to prepare

  • Be able to walk your CV end to end in two minutes, and say why this company specifically.
  • Have your salary expectations, notice period and location constraints ready, and ask for the rest of the loop in writing.
nCino Software Engineer candidate reports ↗
02

Online Technical Assessment

reported

Candidates complete an online assessment to evaluate technical skills.

What to demonstrate

  • Candidates complete an online assessment to evaluate technical skills
  • Depth in OOP (Object-Oriented Programming)

How to prepare

  • Answer aloud and timed: What does the "this" keyword represent within a class context?
  • Answer aloud and timed: How do you approach debugging a complex issue in a production environment?
nCino Software Engineer candidate reports ↗
03

Panel Interviews

reported

Series of interviews with various stakeholders including engineers, managers, and product owners.

What to demonstrate

  • Series of interviews with various stakeholders including engineers, managers, and product owners
  • Depth in OOP (Object-Oriented Programming)

How to prepare

  • Answer aloud and timed: What are the primary differences between a superclass and a subclass?
  • Answer aloud and timed: Tell me about a time you had to explain a complex technical concept to a non-technical stakeholder.
nCino Software Engineer candidate reports ↗

PracHub editorial advice for the preparation topics above.

01

Talk through your process

During coding or whiteboard sessions, explain your logic. We care more about your problem-solving process than a perfect, silent answer.

02

Research our product

Understanding the nCino platform and the financial services domain will help you ask better, more informed questions during your interviews.

03

Be authentic

Our interviewers value honesty. If you don't know an answer, explain how you would go about finding it rather than guessing.

04

If you are referred by a current employee, mention this early in the process

It is often the most effective way to ensure your application receives prompt attention.

Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.

14 technical prompts0 include a worked solution

Collapse a redelivered event batch into per-aggregate high-water marks

easy
hashingat-least-onceaggregation

You drain a batch of up to 5,000,000 events, each (aggregate_id BIGINT, aggregate_version INT, event_type, payload). The log guarantees order within one aggregate only; the batch merges 64 partitions, and a relay failover has redelivered a range, so an older version for an aggregate can appear after a newer one. Given a map of last_applied_version per aggregate, produce the events worth applying, at most one per (aggregate_id, version), plus the count discarded. Target O(n) time. State the memory for 2,000,000 distinct aggregates and what you do when it does not fit.

Approach
  1. One pass, one hash map from aggregate_id to the highest version kept, and a discard counter. An event whose version is at or below last_applied_version for its aggregate is dropped without further work, which is the whole reason the event carries its version rather than a delta. O(n) expected time, O(d) space in distinct aggregates.
  2. Keep the maximum, never the last occurrence. The redelivered range means the final appearance of an aggregate in the batch can be an older version than one seen earlier in the same batch, so last-wins applies stale state over newer state and the projection regresses with no error anywhere.
  3. Cost the memory instead of calling it large: an 8-byte key plus a 4-byte version is 12 bytes of payload, and an open-addressed table held at a 0.7 load factor costs roughly 17 bytes per entry before per-slot metadata, so 2,000,000 aggregates is tens of megabytes in a native layout and several times that in a runtime that boxes both key and value.
  4. If the distinct set exceeds memory, partition on hash(aggregate_id) mod P and reduce each partition independently. Every event for one aggregate hashes to the same partition, so the per-partition result is exact and the merge is concatenation rather than a second reduction.
Follow-up
  • The payload is a patch rather than a snapshot, so applying only the highest version loses the intermediate changes. What changes in your reduction?
  • How do you detect that version 7 arrived while version 6 was never delivered, and what should the consumer do about the gap?

Track a rolling failure rate per destination for circuit decisions

easy
sliding windowring buffercircuit breaker

The egress service delivers about 1,500 webhooks per second across roughly 40,000 destinations, each call bounded by a 10 second timeout. Maintain, per destination, the failure rate over the trailing 60 seconds so a caller can ask before dispatch whether the circuit should open. Attempts arrive as (destination_id, finished_at_ms, outcome). Requirement: amortised O(1) per attempt, with total memory bounded by the destination count rather than by traffic. Give the structure, its exact memory, and the rule that stops a destination with three attempts from opening a circuit.

Approach
  1. Name the exact-deque version and then reject it as the default. Holding timestamps and advancing a tail pointer past anything older than now minus 60 seconds is a correct two-pointer window at amortised O(1) per attempt, but its memory tracks in-window traffic, so one destination in a retry storm holds hundreds of thousands of entries while thousands of quiet destinations hold none.
  2. Use a ring of 60 one-second buckets per destination, each bucket a pair of counters for attempts and failures. On an attempt, advance the ring by the elapsed whole seconds, zeroing at most min(elapsed, 60) buckets, then increment the head. That is amortised O(1) with a fixed footprint per destination.
  3. State the footprint: 60 buckets times two 4-byte counters is 480 bytes of payload per destination, so 40,000 destinations is roughly 20 to 25 MB with per-entry overhead, bounded by the catalogue rather than by the rate. The cost is granularity, since the oldest bucket ages out in whole seconds, which is far tighter than the decision needs.
  4. Require a minimum sample before the circuit may open. A destination with three attempts and three failures reads as 100 percent and is not evidence; a floor of roughly 20 attempts in the window makes the ratio meaningful, and below that floor use a run of consecutive failures as the trigger instead.
Follow-up
  • The fleet is 30 instances and each sees roughly a thirtieth of a destination's traffic. Where does the rate actually live, and what does a per-instance answer get wrong?
  • A destination answers in 9.5 seconds and succeeds. It is not failing but it is consuming your per-destination concurrency. What signal should open the circuit here?

Archive a resource graph without breaking live references or recursing

medium
graph traversaltopological ordertenant isolation

Resources reference other resources within a tenant; for the largest tenant the reference table holds up to 2,000,000 nodes and 8,000,000 edges. Archiving a resource must archive everything reachable from it that nothing outside the set still references, refuse when a live external referrer exists, and terminate when references form cycles, which they legitimately do. Produce the archive order and the refusal list, targeting O(V+E). Say what stops the traversal crossing a tenant boundary, and why recursion is the wrong control structure at this size.

Approach
  1. Load the subgraph with the tenant predicate on both endpoints of the edge, not only on the side you started from. Scoping the left table alone is the classic cross-tenant leak: one mis-entered edge then pulls another tenant's resources into the traversal and, worse, into the archive.
  2. Traverse iteratively with an explicit stack. A 2,000,000-node graph can hold a chain deep enough to exhaust a native stack in the low tens of thousands of frames, and that failure is a process crash rather than an error you can return.
  3. Treat cycles as data rather than corruption: compute strongly connected components with Tarjan in O(V+E) using its own explicit stack, then condense. The condensation is a DAG, so a topological order over it gives the archive order, and every member of a component archives in one transaction because no order within a cycle is valid.
  4. Decide refusals with reverse edges. A candidate is archivable only if every in-edge originates inside the candidate set, so build the transpose or count in-degrees restricted to the visited set, and emit each blocked resource with the id of the external referrer, which is the only part of the answer an operator can act on.
Follow-up
  • The graph is read in one query and the archive writes a minute later. What can change in between, and how do you make the write safe?
  • The candidate set is 400,000 resources. Is that one transaction, and if not, what does a half-finished archive look like to a reader?

Built from the rounds and topics nCino candidates report.

Small steps. Visible outcomes.0 / 7 completed
ONE WEEK · YOUR PACE

Prepare, practise & reflect

One practical outcome each day. Spend longer where you need it.

0 / 7 done
01Map the nCino loop
  • Write out the reported sequence: Recruiter Screening, Online Technical Assessment, Panel Interviews.
  • For each round, write one sentence on what it is judging, from the description above, and mark the one you are least ready for.

Deliverable: A one-page map of the 3 reported rounds, with the weakest marked.

02Work OOP (Object-Oriented Programming)
  • Spend the session on OOP (Object-Oriented Programming), which nCino candidates report being tested on.
  • Write one worked example in OOP (Object-Oriented Programming) and time yourself on it.

Deliverable: One timed worked example in OOP (Object-Oriented Programming).

03Work Programming Assessments / Coding Challenges
  • Spend the session on Programming Assessments / Coding Challenges, which nCino candidates report being tested on.
  • Write one worked example in Programming Assessments / Coding Challenges and time yourself on it.

Deliverable: One timed worked example in Programming Assessments / Coding Challenges.

04Work System Design / Architecture Design (Whiteboard)
  • Spend the session on System Design / Architecture Design (Whiteboard), which nCino candidates report being tested on.
  • Write one worked example in System Design / Architecture Design (Whiteboard) and time yourself on it.

Deliverable: One timed worked example in System Design / Architecture Design (Whiteboard).

05Answer out loud: Technical Fundamentals and OOP
  • Answer aloud, timed: What is the difference between an instantiated class and a class definition?
  • Answer aloud, timed: Can you explain the concept of inheritance and how it applies to your past projects?

Deliverable: Spoken answers to 2 reported Technical Fundamentals and OOP question(s), under time.

06Answer out loud: Behavioral and Cultural Alignment
  • Answer aloud, timed: Tell me about a time you had to explain a complex technical concept to a non-technical stakeholder.
  • Answer aloud, timed: How do you handle situations where your opinion on a technical direction differs from your team's?

Deliverable: Spoken answers to 2 reported Behavioral and Cultural Alignment question(s), under time.

07Answer out loud: System Design and Problem Solving
  • Answer aloud, timed: How would you design a database schema for a university student management system?
  • Answer aloud, timed: Write a program to count the occurrences of each word in a string.

Deliverable: Spoken answers to 2 reported System Design and Problem Solving question(s), under time.

Expand any day for tasks and deliverables. Your progress is saved on this device.

Behavioural rounds judge the decision you made and what it cost.

Tell me about a time you had to explain a complex technical concept to a non-technical stakeholder.

medium
Behavioral and Cultural Alignment

Tell me about a time you had to explain a complex technical concept to a non-technical stakeholder.

Approach
  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.
Follow-up
  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

How do you handle situations where your opinion on a technical direction differs from your team's?

medium
Behavioral and Cultural Alignment

How do you handle situations where your opinion on a technical direction differs from your team's?

Approach
  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.
Follow-up
  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

What is your process for learning new technologies or frameworks on the fly?

medium
Behavioral and Cultural Alignment

What is your process for learning new technologies or frameworks on the fly?

Approach
  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.
Follow-up
  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

Describe a project you are particularly proud of and your specific contribution to its success.

medium
Behavioral and Cultural Alignment

Describe a project you are particularly proud of and your specific contribution to its success.

Approach
  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.
Follow-up
  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

Why are you interested in working at nCino, and what do you hope to contribute to our team?

medium
Behavioral and Cultural Alignment

Why are you interested in working at nCino, and what do you hope to contribute to our team?

Approach
  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.
Follow-up
  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?
  • 01

    Tell me about a time you had to explain a complex technical concept to a non-technical stakeholder.

  • 02

    How do you handle situations where your opinion on a technical direction differs from your team's?

  • 03

    What is your process for learning new technologies or frameworks on the fly?

  • 04

    Describe a project you are particularly proud of and your specific contribution to its success.

PracHub preparation framework ↗
How long should I spend preparing for the technical assessment?

The assessment is designed to test your core fundamentals. Spending 5–10 hours reviewing OOP concepts and practicing basic coding challenges is typically sufficient for most candidates.

nCino Software Engineer candidate reports ↗
What is the biggest differentiator for successful candidates?

Candidates who succeed are those who treat the interview as a collaborative discussion rather than a test. We look for individuals who ask thoughtful questions and demonstrate a genuine interest in our product.

nCino Software Engineer candidate reports ↗
What is the culture like for engineers at nCino?

We value "culture add" over "culture fit." We want people who are vocal, respect diverse opinions, and are committed to continuous improvement.

nCino Software Engineer candidate reports ↗
What topics does nCino test in interviews?

nCino interviews most often cover Stakeholder Communication, Communication Skills, Salesforce Platform, UX/UI Design, and Salesforce Administration. The exact emphasis depends on the specific role you apply for.

nCino Software Engineer candidate reports ↗
Sources & methodology 3 sources ↗

No official company page is cited. Rounds and questions come from candidate reports and PracHub editorial material; each source shows the date it was read.