Torch Dental Software Engineer Interview Guide

The 60-second brief

As a Software Engineer at Torch Dental, you are at the intersection of modernizing dental procurement and supply chain management. Your work directly impacts how dental practices source essential equipment and supplies, effectively digitizing a historically fragmented industry. You will build and maintain the platforms that allow practitioners to focus on patient care rather than administrative overhead. The role demands a balance of technical rigor and product-minded thinking. You will be expected to contribute to the full software development lifecycle, from architecting scalable backend services to ensuring a seamless frontend experience for users.

This guide is scoped to a Software Engineer candidate at Torch Dental.

Focus areas

• System Design
• Coding Interviews
• API Design

The Torch Dental interview process

Torch Dental candidates report 5 rounds over 4-6 weeks. The stages below are what candidates describe, not a published process.

Introductory Call

Initial call to gauge interest and baseline experience.

What to demonstrate

• Initial call to gauge interest and baseline experience
• Depth in System Design

How to prepare

• Answer aloud and timed: Implement a function to solve a specific data manipulation task.
• Answer aloud and timed: Describe your process for debugging a complex issue in a production environment.

Coding Challenges

Assessment of technical capabilities through coding challenges.

What to demonstrate

• Assessment of technical capabilities through coding challenges
• Depth in System Design

How to prepare

• Answer aloud and timed: How do you ensure your code is testable and scalable?
• Answer aloud and timed: Explain the trade-offs of the tech stack you have used in your most recent project.

System Design Discussion

Discussion focused on system design principles.

What to demonstrate

• Discussion focused on system design principles
• Depth in System Design

How to prepare

• Answer aloud and timed: Walk through the logic behind a recent technical decision you made.
• Answer aloud and timed: How would you design an API to handle high-frequency requests?

Project Experience Deep-Dive

In-depth discussion of past project experiences.

What to demonstrate

• In-depth discussion of past project experiences
• Depth in System Design

How to prepare

• Answer aloud and timed: What are the considerations when migrating a legacy service to a new architecture?
• Answer aloud and timed: How do you approach database schema design for a multi-tenant application?

Final Rounds

Intensive rounds involving multiple stakeholders including engineering leadership.

What to demonstrate

• Intensive rounds involving multiple stakeholders including engineering leadership
• Depth in System Design

How to prepare

• Answer aloud and timed: Explain how you would optimize a slow-performing query or service.
• Answer aloud and timed: How do you balance feature delivery speed with technical debt?

Where candidates lose points

Structure your answers

Use the STAR method (Situation, Task, Action, Result) for behavioral questions to keep your responses concise and impactful.

Focus on the "Why

Don't just explain what you did; explain the trade-offs you considered and why you chose your specific path.

Vet your interviewers

Just as they are evaluating you, take the opportunity to ask thoughtful questions about the team’s culture, technical challenges, and roadmap.

Be prepared for ambiguity

Startups often face ill-defined problems. Show that you are comfortable asking clarifying questions to narrow down the scope.

Questions & practice

Implement a function to solve a specific data manipulation task.

Medium · Technical & Coding Proficiency

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?

Explain the trade-offs of the tech stack you have used in your most recent project.

Medium · Technical & Coding Proficiency

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?

Walk through the logic behind a recent technical decision you made.

Medium · Technical & Coding Proficiency

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 do you approach database schema design for a multi-tenant application?

Medium · System Design & Architecture

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?

Explain how you would optimize a slow-performing query or service.

Medium · System Design & Architecture

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?

How do you ensure your code is testable and scalable?

Medium · Technical & Coding Proficiency

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?

How would you design an API to handle high-frequency requests?

Medium · System Design & Architecture

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?

What are the considerations when migrating a legacy service to a new architecture?

Medium · System Design & Architecture

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?

How do you balance feature delivery speed with technical debt?

Medium · System Design & Architecture

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?

Describe your process for debugging a complex issue in a production environment.

Medium · Technical & Coding Proficiency

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 Torch Dental candidates report.

Day 1 — Map the Torch Dental loop

• Write out the reported sequence: Introductory Call, Coding Challenges, System Design Discussion, Project Experience Deep-Dive, Final Rounds.
• 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 5 reported rounds, with the weakest marked.

Day 2 — Work System Design

• Spend the session on System Design, which Torch Dental candidates report being tested on.
• Write one worked example in System Design and time yourself on it.

Deliverable: One timed worked example in System Design.

Day 3 — Work Coding Interviews

• Spend the session on Coding Interviews, which Torch Dental candidates report being tested on.
• Write one worked example in Coding Interviews and time yourself on it.

Deliverable: One timed worked example in Coding Interviews.

Day 4 — Work API Design

• Spend the session on API Design, which Torch Dental candidates report being tested on.
• Write one worked example in API Design and time yourself on it.

Deliverable: One timed worked example in API Design.

Day 5 — Answer out loud: Technical & Coding Proficiency

• Answer aloud, timed: Implement a function to solve a specific data manipulation task.
• Answer aloud, timed: Describe your process for debugging a complex issue in a production environment.

Deliverable: Spoken answers to 2 reported Technical & Coding Proficiency question(s), under time.

Day 6 — Answer out loud: System Design & Architecture

• Answer aloud, timed: How would you design an API to handle high-frequency requests?
• Answer aloud, timed: What are the considerations when migrating a legacy service to a new architecture?

Deliverable: Spoken answers to 2 reported System Design & Architecture question(s), under time.

Day 7 — Answer out loud: Behavioral & Leadership

• Answer aloud, timed: Describe a time you disagreed with a product requirement; how did you resolve it?
• Answer aloud, timed: Tell me about a time you had to mentor a junior engineer or explain a complex concept to a non-technical stakeholder.

Deliverable: Spoken answers to 2 reported Behavioral & Leadership question(s), under time.

Behavioural preparation

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

Describe a time you disagreed with a product requirement; how did you resolve it?

Medium · Behavioral & Leadership

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 you had to mentor a junior engineer or explain a complex concept to a non-technical stake

Medium · Behavioral & Leadership

Tell me about a time you had to mentor a junior engineer or explain a complex 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 changing priorities in a fast-paced startup environment?

Medium · Behavioral & Leadership

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 approach to giving and receiving constructive code review feedback?

Medium · Behavioral & Leadership

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?