The product
What is FDE Interview Prep?
Interview preparation for forward deployed engineer roles, run by SourceStrongAI. You practice timed cases against an AI customer who holds facts back until you ask the right questions, and your score quotes what you said. You also get 180 interview questions, each with a framework for answering it and 106 lessons written round by round so far.
How is this different from LeetCode-style prep?
Algorithm practice trains one kind of problem. This trains the open-ended one, out loud: scoping a vague customer problem with the customer in the room.
How does the AI scoring work?
Each run is scored on eight skills, each against written anchors, and a score above one on any skill needs a quote of your own words as its evidence. The AI can still get it wrong. Treat the score as feedback on your practice, not a verdict on how an interview will go.
Is it useful early in my career?
Yes. The case needs no work history: it trains asking the right questions and planning out loud, which a first job rarely teaches, and the first module starts from what the role is.
The free case
Is the free case really free?
Yes. It costs nothing and needs no card. It does need a free account, so you sign in first, with Google or with a link we email you. A free account gets two scored 10-minute runs of the free case a day, and one scored run of it at full length, in all.
Why do I sign in before the free case starts?
Every run talks to a real AI model, which costs us money each time, so an account is how we keep free runs fair for everyone. It also keeps your transcript and your score, so you can come back to them. There is no password and no card.
What happens in the free case?
You meet an AI customer with a vague problem, and a 10-minute clock starts. Ask questions to find out what they have not told you, plan on the board, and submit. Your score comes back with quotes of your own words and the first thing to fix, the facts you found and missed, with the question that finds each, and a strong run's board beside yours.
Pro, the free trial and paying
How much does Pro cost?
$10/month, billed annually ($119.99 a year), or $19.99/month, billed monthly. Those are the full prices. In many countries Pro costs less, and the pricing page shows the price for yours.
How does the free trial work?
Pro starts with a 7-day free trial on either plan. You enter your card at checkout, and nothing is charged until the trial ends. Cancel in Billing before day 7 and you pay nothing, and Pro stays on until the trial ends. We email you three days before it ends. Each account gets one free trial.
Do you offer refunds?
No. Payments for Pro are not refunded, except where the law requires it. The free trial is there so you can try Pro before you pay, and you can cancel anytime: canceling stops the next payment, and Pro stays on to the end of the period you paid for. If a charge looks wrong to you, write to us.
Can I cancel?
Yes, at any time, from Billing in your account. Pro stays on until the end of the trial, month or year you are in, and nothing more is charged. Everything you saved stays yours when Pro ends.
What is the difference between monthly and yearly?
Only how you pay. Yearly is $119.99 a year, which works out to $10 a month: 50% off the monthly price of $19.99. Both renew until you cancel. These are the full prices; the price for your country may be lower.
Can I switch between monthly and yearly?
Yes, from Billing in your account. A switch to yearly starts at once and charges the difference. A switch to monthly starts when the year you paid for ends. During the free trial, a switch keeps the trial and changes what the first payment will be.
What happens if a payment fails?
Stripe tries your card again over the next days. For a renewal, Pro stays on while it does. For the first payment after the free trial, Pro is off until that payment goes through. Update your card in Billing either way. If every try fails, the subscription ends, and everything you saved stays yours.
How is the price for my country set?
Countries are grouped into price tiers by purchasing power, and you see your country's price, laid out the same way. We read the country from your connection. If we can't tell, you see the full price.
What does Pro include?
Everything a free account has, and today all 3 decomposition cases at every length, up to 10 scored runs a day, model answers to 120 Pro interview questions and 94 Pro lessons, and each new one as it is published. Pro includes each new piece as it is published, for as long as you subscribe.
Content and sources
Where do your facts about companies and interviews come from?
From public sources: job postings, careers pages, company blogs, filings, news reports and candidates’ own posts. Every fact cites its source, and each claim behind it holds a quote copied from that source, which two verifiers checked, each on their own. We publish no pass rates, round weights or typical timelines, because no employer publishes them.
Are the model answers from real candidates?
No. Answers to questions about you, such as “tell me about a time you…”, are written in the first person about a fictional project, to show the structure of a strong answer. They are not a real person’s story, and they are not for memorizing: tell yours from your own work.
AI roles and enterprise roles
Is this for AI-lab FDE roles or Palantir-style ones?
Both. Most of the course serves both kinds of role. Modules 8 and 9 (being written) and the AI systems questions lean toward AI roles, and Modules 4 and 7 (being written) toward enterprise and data roles. Setup asks which you are going for, so what you practice first leans that way. Nothing is removed.
Which companies do you cover?
Questions are tagged with a company only where a source ties them to it, and Palantir, Sierra, OpenAI, Cognition, Cohere and Databricks have their own question pages so far. A company gets one once our sources tie enough questions to it.
Your account and privacy
How do I sign in?
With Google, or with a sign-in link we email you. There is no password to remember.
Can I download or delete my data?
Yes, both, yourself, in Settings under Your data. Download gives you one file with everything we hold about you. Delete removes your account and everything in it at once, and cancels a running subscription straight away. It cannot be undone.
Do you sell my data or show ads?
No. We do not sell your data or share it for advertising, we show no ads, and our pages load no third-party tracking or analytics scripts.
Who sees my practice answers?
They are stored with your account so you can read them back, and sent to OpenAI to write the customer’s replies and your score, without your name or email address. We do not publish them, show them to employers, or use them to train AI models.
The full terms are in the terms of use, the privacy policy and cancellation and refunds.