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Lyra Health Software Engineer Interview Guide

Lyra Health Software Engineer interview guide: reported rounds, questions and how candidates describe the process.

The 60-second brief

As a Software Engineer at Lyra Health, you play a vital role in transforming mental health care through technology, empathy, and scale. This position sits at the intersection of complex software engineering and high-impact healthcare services, building systems that connect people with life-changing mental health care. Your contributions directly influence how patients access care, how providers manage their workflows, and how the business scales its clinical operations. The role demands a high degree of technical ownership, whether you are building resilient backend microservices, crafting intuitive full-stack applications, or integrating enterprise tools. You will work within cross-functional product and engineering teams, collaborating closely with product managers, designers, and clinical operations partners.

This guide is scoped to a Software Engineer candidate at Lyra Health.

Focus areas

  • Full-Stack Engineering
  • Salesforce Development (General)
  • Coding Round

The Lyra Health interview process

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

Recruiter Screening

Initial discussion about your background, motivations, and alignment with the role.

What to demonstrate

  • Initial discussion about your background, motivations, and alignment with the role
  • Depth in Full-Stack Engineering

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.

Technical Evaluations

Assessment of coding capabilities, technical discussions, and behavioral alignment with engineering managers.

What to demonstrate

  • Assessment of coding capabilities, technical discussions, and behavioral alignment with engineering managers
  • Depth in Full-Stack Engineering

How to prepare

  • Answer aloud and timed: How do you manage database migrations and schema updates in a zero-downtime deployment environment?
  • Answer aloud and timed: Can you explain how you approach debugging a complex performance bottleneck in a distributed backend system?

Conversations with Leaders

Opportunities to speak with various engineering leaders and team members about day-to-day life.

What to demonstrate

  • Opportunities to speak with various engineering leaders and team members about day-to-day life
  • Depth in Full-Stack Engineering

How to prepare

  • Answer aloud and timed: How do you ensure high availability and fault tolerance in your service architecture?
  • Answer aloud and timed: Write a function to parse and validate a complex JSON payload containing nested user preferences.

Where candidates lose points

Communicate your thought process

Interviewers at Lyra Health evaluate how you think just as much as your final answer. Talk through your assumptions, explore alternative approaches out loud, and invite feedback as you solve coding or design problems.

Connect with the mission

Ground your behavioral answers and your "Why Lyra?" response in a genuine appreciation for mental health care and patient impact. Showing that you care about the real-world utility of your software resonates strongly with engineering leaders.

Prepare structured behavioral examples

Use the STAR method (Situation, Task, Action, Result) to frame your stories about past projects, technical disagreements, and production incidents. Keep your examples concise and focus heavily on your specific contributions and learnings.

Ask thoughtful questions

Use the time at the end of your interviews to ask about engineering culture, deployment pipelines, and how teams balance feature delivery with technical debt. Thoughtful questions demonstrate your maturity and proactive engagement with the role.

Questions & practice

Write a function to parse and validate a complex JSON payload containing nested user preferences.

Medium · Coding and Problem Solving

Approach

  1. Say what the runtime actually does before reasoning about the code.
  2. Name what is shared across threads and what owns each piece of state.
  3. Identify the window where an invariant is briefly untrue.
  4. Distinguish a value from a reference to it, and say which one you handed out.

Follow-up

  • What happens if two callers reach this at the same time?
  • Where could this allocate more than you expect?

Given an array of log timestamps, implement an algorithm to find peak usage intervals within a specified windo

Medium · Coding and Problem Solving

Given an array of log timestamps, implement an algorithm to find peak usage intervals within a specified window.

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.

Follow-up

  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

How would you refactor a monolithic service method that has accumulated excessive technical debt and tight cou

Medium · Coding and Problem Solving

How would you refactor a monolithic service method that has accumulated excessive technical debt and tight coupling?

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.

Follow-up

  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

Why do you want to join Lyra Health, and what connects you to our mission of transforming mental health care?

Medium · Behavioral and Cultural Alignment

Approach

  1. Name the grain you start from and join outward from it.
  2. Check whether any join is one-to-many before aggregating, or the sums inflate.
  3. Say which index the query would use, and what makes it unusable.
  4. Handle the rows that do not match: that is usually the actual question.

Follow-up

  • How does the query change if that join becomes one-to-many?
  • What happens to this when the table is ten times larger?

Hold a per-tenant active cap against concurrent creates

Hard · write skew · isolation levels · constraints

A tenant on the standard plan may hold at most 50 resources with status='active'. The create handler runs SELECT count(*) FROM resource WHERE tenant_id = $1 AND status = 'active', compares to 50, then inserts. Two creates arrive 3 ms apart on different instances and the tenant lands at 51. Name the anomaly, say whether PostgreSQL 16 READ COMMITTED or REPEATABLE READ prevents it and why, then give an implementation that holds the cap at READ COMMITTED with the exact statements. Finally, say what changes when the cap is 'at most one running export per tenant' on job_run.

Approach

  1. Name it: write skew. The two transactions read an overlapping set and write disjoint rows, so there is no row-level conflict for the engine to detect and each commit is individually legal.
  2. Rule out the levels precisely. READ COMMITTED takes a fresh snapshot per statement and takes no lock on the counted rows, so both see 49. PostgreSQL's REPEATABLE READ is snapshot isolation: it removes non-repeatable reads and phantoms within the snapshot but still admits write skew, because the anomaly is not a re-read of a changed row, it is a read of a set that a concurrent transaction invalidates. Only SERIALIZABLE closes it, by tracking the read dependency and aborting one transaction with SQLSTATE 40001 — a guarantee that exists only if the application re-runs the whole transaction from the read.
  3. Convert the set predicate into a single-row conflict: keep tenant.active_resource_count and run UPDATE tenant SET active_resource_count = active_resource_count + 1 WHERE tenant_id = $1 AND active_resource_count < 50 in the same transaction as the INSERT. Zero affected rows is the cap, returned as 409. The row lock serialises the decision at any isolation level, and contention is bounded to one tenant's row — which is also the fair-scheduling unit, unlike a global counter that would convoy every tenant behind one row.
  4. State the cost you just took on: a counter is a second source of truth that can drift, so every path that changes status must adjust it inside the same transaction, and a periodic reconciliation has to exist, with resource_revision as the authority for what the count should have been.

Follow-up

  • A resource moves from archived back to active. Which statements change, and what breaks if the counter update and the status change land in different transactions?
  • The cap becomes plan-dependent and a plan can change mid-month. Where does the number 50 live, and who reads it?

What languages and frameworks do you have the most professional experience with, and how do you decide which t

Medium · Technical and Domain Knowledge

What languages and frameworks do you have the most professional experience with, and how do you decide which tool is best for a given problem?

Approach

  1. Clarify what is being asked and what a complete answer contains.
  2. State your assumptions explicitly before working the problem.
  3. Say what you would check first and why it is the highest-information step.
  4. Work from the requirement backwards to the design.

Follow-up

  • What assumption would you test first?
  • How would you know your answer was wrong?

Walk me through how you would design a secure API endpoint that handles sensitive user data in a healthcare co

Medium · Technical and Domain Knowledge

Walk me through how you would design a secure API endpoint that handles sensitive user data in a healthcare context.

Approach

  1. Say who the caller is and what they do when the call fails halfway.
  2. Define the identity of a request so a retry cannot double-apply it.
  3. Separate accepted, pending, failed and confirmed; they are different facts.
  4. Design the error taxonomy before the success shape; callers branch on it.

Follow-up

  • What happens if the caller retries after a timeout?
  • How does a client discover it is on an old version of this contract?

How do you manage database migrations and schema updates in a zero-downtime deployment environment?

Medium · Technical and Domain Knowledge

Approach

  1. Clarify what is being asked and what a complete answer contains.
  2. State your assumptions explicitly before working the problem.
  3. Say what you would check first and why it is the highest-information step.
  4. Work from the requirement backwards to the design.

Follow-up

  • What assumption would you test first?
  • How would you know your answer was wrong?

How do you ensure high availability and fault tolerance in your service architecture?

Medium · Technical and Domain Knowledge

Approach

  1. Fix the scope first: who calls this, how often, and what they do when it fails.
  2. Name the read and write paths separately; they rarely have the same bottleneck.
  3. Choose a partition key and say what query it makes expensive.
  4. State the consistency you need, and where you are willing to be stale.

Follow-up

  • What breaks first when traffic grows ten times?
  • How does this behave when that dependency is down for an hour?

Walk through your approach to writing comprehensive unit and integration tests for a newly built feature.

Medium · Coding and Problem Solving

Approach

  1. Say who the caller is and what they do when the call fails halfway.
  2. Define the identity of a request so a retry cannot double-apply it.
  3. Separate accepted, pending, failed and confirmed; they are different facts.
  4. Design the error taxonomy before the success shape; callers branch on it.

Follow-up

  • What happens if the caller retries after a timeout?
  • How does a client discover it is on an old version of this contract?

Can you explain how you approach debugging a complex performance bottleneck in a distributed backend system?

Medium · Technical and Domain Knowledge

Approach

  1. Establish what changed and when, before forming any theory.
  2. Pick a bisection that eliminates candidates whichever way it turns out.
  3. Check the instrumentation before believing the symptom.
  4. Separate the trigger from the cause; the deploy is rarely the bug.

Follow-up

  • What would you look at first, and what would it rule out?
  • How would you tell a cause from a coincidence here?

Suggested practice checklist

Built from the rounds and topics Lyra Health candidates report.

Day 1 — Map the Lyra Health loop

  • Write out the reported sequence: Recruiter Screening, Technical Evaluations, Conversations with Leaders.
  • 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.

Day 2 — Work Full-Stack Engineering

  • Spend the session on Full-Stack Engineering, which Lyra Health candidates report being tested on.
  • Write one worked example in Full-Stack Engineering and time yourself on it.

Deliverable: One timed worked example in Full-Stack Engineering.

Day 3 — Work Salesforce Development (General)

  • Spend the session on Salesforce Development (General), which Lyra Health candidates report being tested on.
  • Write one worked example in Salesforce Development (General) and time yourself on it.

Deliverable: One timed worked example in Salesforce Development (General).

Day 4 — Work Coding Round

  • Spend the session on Coding Round, which Lyra Health candidates report being tested on.
  • Write one worked example in Coding Round and time yourself on it.

Deliverable: One timed worked example in Coding Round.

Day 5 — Answer out loud: Technical and Domain Knowledge

  • Answer aloud, timed: What languages and frameworks do you have the most professional experience with, and how do you decide which tool is best for a given problem?
  • Answer aloud, timed: Walk me through how you would design a secure API endpoint that handles sensitive user data in a healthcare context.

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

Day 6 — Answer out loud: Coding and Problem Solving

  • Answer aloud, timed: Write a function to parse and validate a complex JSON payload containing nested user preferences.
  • Answer aloud, timed: Given an array of log timestamps, implement an algorithm to find peak usage intervals within a specified window.

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

Day 7 — Answer out loud: Behavioral and Cultural Alignment

  • Answer aloud, timed: Tell me about yourself and walk me through your past work experience, highlighting a project where you took ownership of a major component.
  • Answer aloud, timed: Describe a time when you had a disagreement with a product manager or cross-functional partner regarding technical debt versus feature delivery. How did you resolve it?

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

Behavioural preparation

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

How do you handle edge cases, null values, and asynchronous operations in your daily coding work?

Medium · Coding and Problem Solving

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?

Tell me about yourself and walk me through your past work experience, highlighting a project where you took ow

Medium · Behavioral and Cultural Alignment

Tell me about yourself and walk me through your past work experience, highlighting a project where you took ownership of a major component.

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 time when you had a disagreement with a product manager or cross-functional partner regarding techn

Medium · Behavioral and Cultural Alignment

Describe a time when you had a disagreement with a product manager or cross-functional partner regarding technical debt versus feature delivery. How did you resolve it?

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 a situation where a critical production bug occurs and you need to coordinate a fix under pr

Medium · Behavioral and Cultural Alignment

How do you handle a situation where a critical production bug occurs and you need to coordinate a fix under pressure?

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?

Tell me about a time when you mentored a junior engineer or helped improve team engineering processes.

Medium · Behavioral and Cultural Alignment

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?