Virtual Onsite

Virtual Onsite interview or Final Round interview is usually a 4-6 hours long process, not only mentally challenging but also physically demanding.

To help our users best prepare for their dream company job interviews, we are excited to launch an onsite mock interview service, which simulates a real onsite interview experience to help you become 100% job interview-ready.


1. Which company/role's onsite mock interview service is available?

We currently offer the following roles: data scientist, software engineer, data engineer, machine learning engineer, product analyst, and business intelligence engineer.

You can almost request any technical roles in data, software engineering, or machine learning related. We have a very strong team of mentors from major tech companies including FAANG.

2. How does it work?

  1. Upon successful payment, our team will reach out to you and schedule a free quick chat to understand your needs;

  2. Our team will assemble a team of 4-5 mentors who all have hiring experience, based on your specific needs, to form a hiring committee.
  3. We will schedule the mock interview for a weekend (mostly Saturday), and it will last about 4-5 hours.
  4. you will meet 5 different mentors (all have hiring experience) that form a hiring committee and receive detailed feedback, including hire or no hire decisions.

3. What I will get?

Depends on the company/role, you will meet 4-5 different experienced hiring managers and senior individual contributors, which simulate a real final round interview process.

Those mentors will be carefully selected by our team to best represent the company and role you are interviewing with.

After the onsite mock interview, every interviewer will submit their feedback, and you will receive comprehensive feedback documents within 24 hours on how to improve your interview skills.

4. Will I get a refund?

Absolutely! As long as you give us at least 48 hours (2 days) notice, we will refund you 100%. If you didn't show up and didn't notify us, we will not be able to refund you.

5. Can I cancel/reschedule?

Absolutely! As long as you give us one week's notice, since our mentors are all busy as you, and it's really hard to coordinate everyone's time. Once it's scheduled, we would like to ask that you try keeping the originally planned mock interview if possible.

Here are two examples:

1. Facebook data scientist virtual onsite mock interview:

  1. Analysis: Product. KPIs to evaluate a new feature/product (45 minutes);
  2. Analysis: Applied data. Engagement dropped 15 percent. What would you do? (45 minutes);
  3. Quantitative analysis: probability, prior/post probability, a/b testing (45 minutes);
  4. Technical analysis: SQL (45 minutes);

2. Amazon data scientist virtual onsite mock interview:

  1. SQL & data modeling: write a query to recommend products that can be used for subscription services. (1 hour);
  2. Machine Learning: how to prevent over-fitting, how to measure variable importance? (1 hour);
  3. Leadership/Behavioral questions, aka bar raiser interview. How do you handle an impossible deadline? (1 hour)
  4. Statistics. How do you explain the p-value to non-technical people? How do you handle Simpson's paradox?  (1 hour).



  • Founder of, and
  • Most recently a senior manager at Apple, where I built and hired a world-class machine learning team of data scientists, software engineers, data engineers, and product managers.
  • Head of data science at Chegg, research scientist at Amazon, serial entrepreneur.

“You will first book a 45 mins chat (FREE) with me to collect requirements. Our team will then assemble an onsite mock interview team: 4-5 experienced mentors and set up this 4 -5 hours-long onsite mock interview for you.”

$ 1499 ⏰ 4 hours

Get access to Leon Wei's calendar after Stripe process your payment, fully refundable if not 100% satisfied.

⏰ Virtual Onsite with Leon Wei for $1499

The easiest way to accomplish something is to hire someone who's done it

Selected Customers Testimonials

50% Salary Increase!

Thank you so much @Leon !

Your advice and coaching are extremely helpful for preparations for the interviews. The timeline and pacing you helped plan worked out very well.

It kept me on the right track. The exercise on coding and data analytics you recommended greatly sharpened my skills to solve the problems during the technical rounds.

The practice to communicate project work to peers is another highlight to help me earn higher score. Again thank you so much for all your advice!

instamentor | customer review
Joey Huang

Machine Learning Engineer

Dream Job Offer from Apple!

Hi @Leon and @Mike ,

Just wanted to share, I accepted an offer from Apple as a Data Engineer and wanted to offer a huge thank you to both of you guys.

Even though I only shared a small time with you both I benefited a lot from your platform and your mock interviews.

Some of the questions you gave during our Data Modeling with you Mike were presented verbatim.


Data Engineer at Apple

The mock interview helped me do it in the right way

I did a SQL Mock interview on Instamentor to gain a better understanding of how SQL interviews are conducted.

Leon (my mentor) came prepared with a realistic case study example tailored specifically towards the company I was interested in. Read more...

The questions and tips he provided were incredibly helpful in my preparation.

My actual interview went in a similar manner and having done the mock interview helped me do it in the right way.

instamentor | customer review

Data Engineer at Square

Extremely valuable!

Shoutout to Leon Wei from

Please do reach out to him if you're looking for career advice, general consulting, or resume feedback. I found his services extremely valuable.

And while you're at it, please do check out SQLPad if you're looking to refresh your SQL concepts.

instamentor | customer review
Jonathan D'Cruz

Data Science Manager at Swiggy

Recommending him!

Shout out to Leon Wei from, recommending him if you are searching for great advises and mentorship for your #datasciences career.

instamentor | customer review
Feng Xue

Senior Data Engineer at T-Mobile

Dream Data Scientist job offer!

I've tried several sites to practice SQL and is my favorite because the questions are well-designed to focus on the most important concepts. Some of the other sites are all over the place.

With, I can focus on questions by skill level or topic, and the number of questions available is a reasonable amount to study for interview prep.

In addition, I got mentoring sessions with Leon and I was impressed at how helpful it was. Leon was calm and knowledgeable, which helped my nerves over my up-coming interview.

He really takes mentoring seriously and it makes a big difference. After practicing my SQL, I got my data science dream job!


Data Scientist

Meticulously prepared and very professional

I signed up on Leon's service and was pleasantly surprised when he helped me out personally on the website. In two mock interviews with him from, he was meticulously prepared and very professional.

Throughout the interview he provided fantastic feedback and frameworks on how to be better prepared for both technical and behavioural aspects of an interview.

He is also a very positive and friendly person and I enjoyed all my interactions with him.

instamentor | customer review
Rahul Nayak

Marketing Analyst

Thank you!

Shoutout to Leon Wei from, recommending him if you are searching for great advices and mentorship for you #datascience career.

instamentor | customer review
Bara Ndiaye

Data Scientist

What made the session successful was the effortlessness in being honest around Leon.

I had my first mentoring call yesterday. The session was to be for 45 mins but lucky for me, Leon did not have a hard stop. We had a detailed discussion around my career history, career transition, stuff I’m good at and enjoy doing/good at but don’t enjoy/not good at and want to improve, not good at and not interested in get the drift). Read more

Leon listened patiently, highlighted areas I needed to work on, pointed out practical considerations, and made gentle suggestions on handling a couple of situations I had bombed (salary negotiation was one).

We covered a lot of ground and had concrete to-dos at the end of the call, but what made the session successful was the effortlessness in being honest around Leon. A mentor needs to identify what is holding the mentee back in their career, and their advice can only be as good as the inputs we give them. Leon made it easy to be authentic. I’ll keep you all posted on my journey!

A Mentee

Data Scientist

I landed the job I wanted at a FAANG company

Joining INSTAMENTOR.COM was very easy, and I quickly found a mentor who is a good match. My mentor was amazing and friendly. He knew all the details and important things that I needed in my job search. I landed the job I wanted at a FAANG company, and we’re still in touch.


Data Scientist, received a dream offer

Instamentor is understanding and accommodating

Although my first mentor was great, I decided to pursue a different career track mid-way. They quickly found me a different mentor after I contacted them, without extra charge.


Recent Graduate

This platform and my mentor have made the job search so much easier

This platform and my mentor have made the job search so much easier for me. All the support and insights from my mentor made me feel so much readier for my interview. This made me walk in completely relaxed and natural in the interview room which got me the job!


Data Engineer

Instamentor helped me connect with a mentor from my dream company

Instamentor helped me connect with a mentor from my dream company. I learned a lot about the culture of the company, the good and bad about working there. He also help me prepare my job interviews by providing mock interviews and resume feedbacks.


Software Engineer

Instamentor hooked me up with a mentor who changed my career

I’m a business analyst and always want to become a data scientist. I’m really glad Instamentor hook me up with a mentor who successfully changed my career path. With my mentor’s guidance, I’m on track learning coding languages that are crucial as a data scientist. The most important thing is that I have gained courage and confidence on my career development.


Data Analyst