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Behavioral
8 months ago
Can you describe a situation where you faced a setback or challenge at work, and what did you learn from it?
UX DesignerTechnical Program ManagerSoftware EngineerML Engineering Manager

Illumina

Capital One

TuSimple

At my previous role, I was leading a fraud detection AI model deployment for a financial services client. The model aimed to reduce fraudulent transactions by 25% while maintaining a low false positive rate.

I was confident in the model’s performance in the test environment, but when we deployed it in production, we noticed an unexpected spike in false positives. Transactions flagged as fraudulent were legitimate, causing disruptions for customers and increasing manual review work. To resolve this, I:

  1. Investigated the issue by comparing training and production data.

  2. Identified data drift—the model was trained on historical data, but recent transaction patterns had changed.

  3. Worked with data engineers to implement real-time data monitoring.

  4. Retrained the model with up-to-date data and adjusted hyperparameters to improve generalization.

This fix reduced false positives by 25%, improved fraud detection accuracy, and ultimately saved $500M in operational savings across multiple initiatives. This experience taught me the importance of continuous model monitoring and proactively accounting for data drift. Now, I always incorporate data validation pipelines and feedback loops into AI deployments to prevent similar issues.

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8 months ago
Behavioral
8 months ago
Describe a time when you failed at work.
Frontend EngineerSoftware EngineerTechnical Program ManageriOS Engineer

Illumina

Epic Systems

Juul Labs

+1

Situation: I was tasked with building a prototype of our DIGITS app on the Hololens 2, a mixed-reality device. This was new territory for us, and I was excited to explore how our telephony experience could translate to AR.



Task: My goal was to create a working demo that integrated our telephony SDK into the Hololens experience using Unity and C#. I had about two weeks to get something functional enough to evaluate viability.



Action: I dove deep into learning Unity3D and Hololens development from scratch, and spent considerable time trying to bridge our SDK — which was built in C++/C# — with the Hololens platform. Despite my efforts, I couldn’t get reliable communication between Unity and our SDK.



Rather than give up, I pivoted and simplified the approach by porting our existing Windows desktop app into the Hololens environment. This at least allowed for basic app functionality and UI testing. Through further research and prototyping, I discovered a key platform limitation: Hololens did not support background notifications, meaning incoming calls couldn’t be surfaced while another app was in use.



Result: I documented everything, demoed the prototype to my manager, and recommended that we pause development until the Hololens platform evolved. While I didn’t deliver the full solution I set out to build, I learned a ton, clearly communicated risks, and saved the team from investing more time into a blocked path. I see this as a failure in the original goal, but a success in terms of ownership, problem-solving, and protecting resources.



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8 months ago
Behavioral
8 months ago
Have you ever had a professional conflict with your manager? Can you tell me about it?
UX DesignerData Engineering ManagerEngineering ManagerUX Researcher

Illumina

Pepperfry Logo

Pepperfry

Huawei Logo

Huawei

In my last role I had to make a UX decision about the product that will balance functionality for the user without compromising performance. After testing a few options and validating it with internal stakeholders I released the updated UX, but then the CEO (who was a heavy user of the product) was against that change. I saw down with him and explained my reasoning and the process that I took to validate the solution, and gave him the option to try it himself on an early version. Once he saw the big picture he agreed that my solution was the right approach, but asked that next time I will consult with him before releasing changes like this. 

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8 months ago
Behavioral
8 months ago
Tell me about a time when you failed badly and what you learned from it?
Product ManagerBackend EngineerTechnical Program ManagerSoftware Engineer

Illumina

JoyTunes Logo

JoyTunes

N26 Logo

N26

+14

I was working on a large scale program that had integration points with Lab and external 3rd party team . We were following a strict timelines and had intially aligned on end to end delivery and various cross coordination effort . since we were dealing with major cross coordination feed files for further processing from 3rd party team we had highlighted the risk to the leadership team but didn't receive a strong follow up on the risk and commitment from the 3rd party organization on the delivery date . This caused us to miss the go live date had to delay . However going forward we had frequent checkpoint calls and also as a backup for testing effort we build mockster and service virutalisation for testing effort so that we can mock the service behavior of the feeds and data that we were supposed to receive from 3rd party team and moved ahead in our schedule .Therefore for all major delivery and critical delivery of the product we assumed variability and defined on the process of backup scenario in case we encounter Andy hurdles / risk

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8 months ago
Behavioral
8 months ago
Tell me about an experience where you lead a team
Full Stack Software EngineerBackend EngineerProduct ManagerTechnical Program Manager

Illumina

Workiva Logo

Workiva

Udacity Logo

Udacity

+2

In my current role, I led a team of 6engineers, 3quality analysts and 3 partner account managers to build and deliver a product for enabling integration with tax authorities government portal and partner tech systems to systematically onboard the partners and consume, validate and pay their invoices in line with local authorities regulatory requirements. My role involved partnering with internal xyz transportation business teams of outbound, import and returns business, financial operations, procurement and controllership teams to align on the business and tech requirements, understand the tech integration dependencies, accounting requirments and define the MVP, change management and then drive the go to market strategy through a dial up. 

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8 months ago
Coding
8 months ago
What is your method for calculating the confidence intervals around a mean in Python?
Machine Learning Engineer

Illumina

Apple Logo

Apple

Mailchimp Logo

Mailchimp

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8 months ago
Behavioral
8 months ago
How would you improve Illumina if you were to get the Full Stack Software Engineer job?
Full Stack Software Engineer

Illumina

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8 months ago
Product SenseProduct Design
8 months ago
Do you have a favourite non-DB product? If so, why? What would you want to change in order to improve it?
Product Manager

Illumina

MobiKwik Logo

MobiKwik

Equinix Logo

Equinix

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8 months ago
Behavioral
8 months ago
What is your most significant accomplishment? Why?
Frontend EngineerProgram ManagerFull Stack Software EngineerData Scientist

Illumina

Cognizant Logo

Cognizant

Babylon Health Logo

Babylon Health

+5

During my career I manage a large number of projects, but one of the most challenging ones was the development and launch of a Telematic Control Unit for an important car maker in Japan. The project is important to me due to technical challenges we faced, the skills I applied and the impact on the company.

As Program manager my role was to lead a cross-functional team including Design Engineers, SW Engineers, Operations teams, Material procurement teams, quality and logistics, among others to successfully launch the product to mass production.

First, I kicked-off the project. For that, I shared with the team the project scope, the goals to achieve, I shared the project plan with key milestones and defined the roles and responsibilities for the different team members.

During execution, to maintain a clear communication, I set up design review sessions with the entire engineering organization to ensure everyone was aligned and fixing potential issues in advance. Besides, I led a weekly core-team meeting where we assigned tasks to team members, and setting clear deadlines for each task. To make these tasks easier to manage, I made sure tasks were broken down into manageable sizes with clear descriptions and acceptance criteria. This helped the team to stay focus on their deliveries and maintain speed.

Another important part was to manages Risks. I worked with the team to identify and classify possible risk that might impact to the project deliverables. We defined a Risk matrix to monitor during the development process, and also a project board with the main KPIs to achieve during each stage of the project.

To ensure quality, we defined different testing processes focused on the design, and the process. We installed specific quality check for the documents and devices delivered for each of the milestones of the PDP, as well as a clear quality control in mass production.

Finally, for transparency, I reported on monthly basis to our company leaders and customer about the project status, focusing on Timing, cost, quality and scope.

By employing these strategies, we successfully launched our module on time matching with all the requirements defined by our customer. This was a great example of teamworking, and taught me the importance of breaking down large projects into smaller and easy to manage pieces. Transparent and clear communication was also a great lesson learned. This approach helped me to improve in leading teams through complex problems.

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8 months ago
Behavioral
8 months ago
Which aspect of Data Scientist role at Illumina excites you the most?
Data Scientist

Illumina

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8 months ago

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