Launch HN: Litebulb (YC W22) – Automating the technical interview

Use Litebulb to get 10x deeper candidate evaluations and run 10x more interviews.

Currently in beta

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Backed by

61ef460ddee6c3459d10b2e3 YCLong

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Here’s how it works

Our reports look like this

Try our interactive demo to see how Litebulb can help you grow your team!

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Our interviews are modern

Litebulb interviews look like everyday dev work. Whether you’re looking for a frontend, backend, or full stack engineer, we have the interviews you’ll need. If we don’t, we can create one for you!

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Realistic Interviews

Litebulb interviews are simulations of regular dev work. Candidates are given production databases, web servers, and apps and build real features.

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Familiar Experience

Interviews are hosted on browser-based VSCode IDEs, setup is instant, and everything is on Github, so candidates feel right at home in a Litebulb interview.

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Modern Reports

Litebulb reviews submissions how a senior engineer would review a code change request. We test for edge cases, performance bottlenecks, scalable design, and code quality.

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Reduce Bias

Every metric we measure is numeric, and every test is deterministic. As a result, you can make hiring decisions based purely on merit.

Candidates love Litebulb interviews!

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…we actually get a lot of these

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Our team has experience from

Shannie Briere

Founding Operations Lead

Vicki Chow

Founding Backend Engineer

Clarence Ng

Senior Frontend Engineer

Aaron Ngu

Fullstack Software Engineer

Shannie Briere

Founding Product Lead

Vicki Chow

Founding Backend Engineer

Clarence Ng

Senior Frontend Engineer

Aaron Ngu

Fullstack Software Engineer




per month billed yearly

Save $600 per year

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Full access to Project Library

3 user accounts

10 interviews/month ($40USD/additional interview)



per month billed yearly

Save $1200 per year

Request demo

Full access to Project Library

Unlimited user accounts

20 interviews/month ($30USD/additional interview)



per month billed yearly

Save $4800 per year

Request demo

Everything in Premium

ATS Integrations

80 interviews/month ($30USD/additional interview)



billed yearly

contact us

Everything in Pro

Custom interviews

200+ interviews/month ($25USD/additional interview)

Let’s have a chat

We’ll show you how to run much better interviews

Frequently asked questions


Litebulb interviews are in the form of take home challenges or onsite interviews (remote or in-person). We currently support three popular engineering tracks:

1. Full Stack Web Engineer

2. Frontend Web Engineer

3. Backend Engineer

As our interviews are multi-tech stack, each interview is some combination of a few of these technologies:

1. Javascript/Typescript

2. Python (Django or Flask)

3. Node.js + Express

4. React.js

5. Golang

6. Ruby on Rails

7. Java Spring Boot

8. Docker

9. GCP or AWS

10. MongoDB, MySQL, or PostgreSQL

We are actively expanding our list of interviews, and are more than happy to partner with you to build interviews that make the most sense for your team!


Projects take anywhere between half an hour to several hours to complete, Litebulb gives recommendations depending on level of experience. As an employer, you can choose to send Litebulb interviews out as take-homes over a few days, or conduct them as a remote onsite over a single sit-down call. Ultimately, you have full control over how long candidates get to complete the interview.


The Litebulb team does not interview your candidates face to face. Rather, we provide you with the environment and tools to allow you to easily interview your candidates face to face. Leave the code evaluation to Litebulb, and you can focus on getting to know your candidates better and gauging their cultural fit.


Litebulb’s auto-evaluation isn’t anything fancy or nebulous. In fact, we intentionally don’t utilize any AI or NLP technology. Our evaluation is simply a long list of true or false statements about someone’s interview submission. Here are some examples:

1. We expect this “Cancel” button to close the popup, if we click on it, does it close the popup?

2. We expect that running this API call with a specific ID returns a specific item, does it?

3. We expect that all newly added identifiers in this commit are in camelCase, are they?

4. We expect that running the linter should produce no warnings and no errors, does it?

The purpose is that Litebulb’s evaluations are 100% deterministic, so there won’t be any questions of accuracy. The only question remaining, what if I want to test for something that Litebulb doesn’t currently test for? Then you should email us at [email protected] to see how we can add these tests in!


All interview submissions are automatically checked against previous submissions of the same interview, so any time we find a suspicious match, a ticket is created and we manually investigate the case. Any interview that is deemed to be widely leaked will be deactivated from future use on the platform, and any candidate deemed to have leaked the project will be banned from the platform.


All of our interviews are hosted on a Github Enterprise organization that we maintain, and all of our interviews are Docker-ized. This means that all a candidate needs to do to get started is to clone the repository and run “docker-compose up –build”, the entire environment will spin up within a local Docker container on their computer, and it usually takes less than 3 minutes to run. The great part about this is that the candidate is truly in their own development environment, using their own IDE, and with access to all the tools that they already have. We’ve found that this method of setting up an environment creates a phenomenal candidate experience.


If you use particularly rare frameworks or libraries, it may happen that Litebulb does not have any interviews that relate close enough to what the role needs. If this is the case, send an email to [email protected] and our team will be happy to work with you to create a new project within your relevant domain and stack!


Yes we do! Our support team is available from Monday to Friday, 9:00AM to 5:00PM PST, so any time you have a question or need help with something, you can reach us at [email protected] and we’ll be happy to help!

Have more questions?

Just reach out, we’re always around to answer any questions.

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