By FDE Interview Prep, a SourceStrongAI company

In this post11 sections
  1. The short answer
  2. What employers publish about online assessments
  3. What candidates report, employer by employer
  4. Assessments that test more than code
  5. AI-run screening interviews
  6. Set up your environment before the link arrives
  7. A practice routine for each format
  8. During the assessment: time, tests and what to submit
  9. Questions people ask
  10. Keep reading
  11. More from the blog

You applied on Monday, and on Wednesday an email arrives with a link, a timer and no human name. For some roles, that link is the first gate: an online assessment on HackerRank, CodeSignal or CoderPad, or an AI that interviews you before a human interviewer does. What is inside varies more than the platform: candidates report SQL, API calls and, in one Salesforce report, an email to a difficult customer, so practice the mix, not only LeetCode. Source 1HackerRank forward deployed engineer interview process (comment by u/pranav_india)PublisherReddit r/developersIndiaSource typecandidate report on RedditSource 2HackerRank forward deployed engineer interview process (comment by u/Strange-Egg5496)PublisherReddit r/developersIndiaSource typecandidate report on RedditSource 3HackerRank Forward Deployed Engineer Online Assessment insights? (post by u/ParticularSpirit3387)PublisherReddit r/leetcodeSource typecandidate report on RedditSource 4HackerRank Forward Deployed Engineer Online Assessment insights? (comment by u/ParticularSpirit3387)PublisherReddit r/leetcodeSource typecandidate report on RedditSource 5Palantir FDSE Interview (Blind thread)PublisherBlindSource typecandidate report on BlindSource 6Forward Deployed Engineer (Agentforce) (comment by u/joemons)PublisherReddit r/SalesforceCareersSource typecandidate report on Reddit It is one stage of the loop; the FDE interview guide covers every round after it.

The short answer

An FDE online assessment is a test you take on your own, through a link, before you talk to an engineer. Employers name the platforms: Palantir’s early-talent timeline starts with a HackerRank coding challenge, and Cresta’s Senior FDE posting starts with a self-paced CoderPad assessment. Source 7Students | Palantir Careers (timeline image: RecruitingTimeline_V3.jpg)PublisherPalantirSource typecompany hiring pageSource 8Senior Forward Deployed Engineer (AI Agent)PublisherCresta (Greenhouse job board)Source typecompany job posting

Rehearse the environment and the mix of tasks. The rest of this post shows what each part looks like, with worked examples, and a practice routine for each format.

What employers publish about online assessments

Start with the employer’s own words, and read the scope of each one carefully.

EmployerWhat it publishes
PalantirIts students and early-talent timeline lists a HackerRank coding challenge as the first step, then a recruiter chat and a technical interview. Source 7Students | Palantir Careers (timeline image: RecruitingTimeline_V3.jpg)PublisherPalantirSource typecompany hiring page
CrestaIts Senior Forward Deployed Engineer posting says the first step after resume review is a self-paced CoderPad technical assessment. Source 8Senior Forward Deployed Engineer (AI Agent)PublisherCresta (Greenhouse job board)Source typecompany job posting
AnthropicIts careers page says technical roles use live coding tools such as Colab and CodeSignal, and that you can look things up. Source 9CareersPublisherAnthropicSource typecompany hiring page
OktaIts intern program page lists a CodeSignal pre-screen first for intern and new-grad technical roles, not FDE roles. Source 10Okta Intern ProgramPublisherOktaSource typecompany job posting
SalesforceA May 2026 careers blog post says technical candidates may complete an assessment demonstrating how they use AI. Source 11Ask a Recruiter: How Do I Get AI-Ready Without a Technical Background?PublisherSalesforceSource typecompany blog

Two notes on that table. Palantir’s timeline is for students and early talent, so it does not tell you what an experienced hire gets. Anthropic describes live coding tools, which is not the same as an unsupervised test. Cresta’s posting is the clearest FDE-specific statement: the assessment exists to let you “showcase your practical coding and problem-solving skills in a real-world environment”. Source 8Senior Forward Deployed Engineer (AI Agent)PublisherCresta (Greenhouse job board)Source typecompany job posting

What candidates report, employer by employer

A report is one person’s account of one process, not the company’s policy. Skim to your employer:

The caveats that matter. One commenter who reported the Palantir OA also promoted a third-party site in the same comment. Source 5Palantir FDSE Interview (Blind thread)PublisherBlindSource typecandidate report on Blind The older Palantir account is for an internship, not an experienced FDSE hire. The Scale AI and Google Cloud reports name neither the platform nor the content.

Two details are worth acting on. One poster in the Anthropic thread wrote that they finished the first question with about 20 minutes left and could not finish the second in time, so budget your minutes. Source 15Anthropic Solutions Architect/Forward Deployed Engineer CodesignalPublisherBlind (teamblind.com)Source typecandidate report on Blind And a second poster on the BCG X role wrote that HR had told them their next round would be “similar to the OA”. Source 16BCG X R1 Interview help for Forward Deployed AI Engineer (post by u/a_legendary_unicorn)PublisherReddit r/developersIndiaSource typecandidate report on RedditSource 17BCG X interview case (post by u/Classic_Comparison90)PublisherReddit r/McKinsey_BCG_BainSource typecandidate report on RedditSource 18BCG X Forward Deployed AI Scientist Recruiting Process (post by u/Warm-Anything9659)PublisherReddit r/MBB_B4_Tech_RolesSource typecandidate report on RedditSource 19BCG X Forward Deployed AI Engineer live coding round (comment by u/Classic_Comparison90)PublisherReddit r/leetcodeSource typecandidate report on Reddit If that holds for you, the assessment is also your preview.

A note on CoderPad

Cresta publishes a self-paced CoderPad step, as above, and it is the clearest FDE-specific description of a take-home-style assessment. Source 8Senior Forward Deployed Engineer (AI Agent)PublisherCresta (Greenhouse job board)Source typecompany job posting Self-paced means a brief to read, a working answer to build and assumptions to state, which is closer to a small ticket than to a puzzle.

Assessments that test more than code

The reports that surprise people are the mixed ones. In the clearest, one candidate reported, in a Salesforce Agentforce FDE thread on Reddit in August 2026, clearing an assessment with four parts: Source 6Forward Deployed Engineer (Agentforce) (comment by u/joemons)PublisherReddit r/SalesforceCareersSource typecandidate report on Reddit

  • a simple string-concatenation coding task;
  • basic SQL;
  • multiple-choice questions about AI;
  • an email reply to a customer with unrealistic demands about shipping an AI system within a week.

One poster reported SQL and API work in HackerRank’s FDE OA, and one commenter reported the same in a Palantir FDSE OA. Source 1HackerRank forward deployed engineer interview process (comment by u/pranav_india)PublisherReddit r/developersIndiaSource typecandidate report on RedditSource 2HackerRank forward deployed engineer interview process (comment by u/Strange-Egg5496)PublisherReddit r/developersIndiaSource typecandidate report on RedditSource 3HackerRank Forward Deployed Engineer Online Assessment insights? (post by u/ParticularSpirit3387)PublisherReddit r/leetcodeSource typecandidate report on RedditSource 4HackerRank Forward Deployed Engineer Online Assessment insights? (comment by u/ParticularSpirit3387)PublisherReddit r/leetcodeSource typecandidate report on RedditSource 5Palantir FDSE Interview (Blind thread)PublisherBlindSource typecandidate report on Blind In these three reports, the assessment looked like a slice of the job. One report from Anthropic, for a role that is not an FDE title, shows how far that can go. One Blind poster was invited, in March 2025, to a “55 min code signal round for prompt engineering” for the Applied AI Product Engineer role. Source 23Anthropic Applied AI product engineer roundsPublisherBlind (teamblind.com)Source typecandidate report on BlindSource 24Anthropic Applied AI product engineer InterviewPublisherBlind (teamblind.com)Source typecandidate report on Blind A commenter who took it said you type plain text into a .md file and the test runner uses it as your prompt, and that working this out cost them about 10 minutes. Source 23Anthropic Applied AI product engineer roundsPublisherBlind (teamblind.com)Source typecandidate report on BlindSource 24Anthropic Applied AI product engineer InterviewPublisherBlind (teamblind.com)Source typecandidate report on Blind

Here is how we practice each non-algorithm part at OA size, and the trap in each.

The SQL task

The reports say only “SQL” or “basic SQL”, so practice a join with an aggregate and one trap. A classic one: revenue and customer count by plan, including customers who have no paid orders.

SELECT c.plan,
  COUNT(DISTINCT c.id) AS customers,
  COALESCE(SUM(o.amount), 0) AS revenue
FROM customers c
LEFT JOIN orders o
  ON o.customer_id = c.id
 AND o.status = 'paid'
GROUP BY c.plan;

The filter on o.status sits in the ON clause on purpose. Move it to WHERE and the left join quietly becomes an inner join: plans with no paid orders vanish, and customers without a paid order drop out of every plan’s count. A test with a customer who has no paid orders catches both. For more, try the free SQL questions on the latest status per ticket and join fan-out that inflates revenue.

The API task

No report describes the API task in detail, so practice the version that covers the most ground: an endpoint with pagination and at least one failure.

import time

RETRY = {429, 500, 502, 503, 504}

def fetch_all(get, url, tries=4):
    items, cursor = [], None
    while True:
        for n in range(tries):
            r = get(url, params={"cursor": cursor})
            if r.status_code not in RETRY:
                break
            if n < tries - 1:
                time.sleep(2 ** n)
        r.raise_for_status()
        body = r.json()
        items += body["data"]
        cursor = body.get("next_cursor")
        if not cursor:
            return items

It retries only what is worth retrying (429 and the 5xx codes that are usually temporary), backs off, does not wait after the last try, and raises on a 404 instead of looping. A 429 response may include a Retry-After header (RFC 6585, section 4); if the task mentions it, honor it. The free question on retry with exponential backoff and jitter takes this further.

The customer email

This part tests judgment in writing. A reply that works leads with what you can deliver, names what you cannot, gives a path to it, and asks for one decision.

Subject: What can be live by Friday

Hi Dana,

By Friday: the agent answers
order-status questions for your
pilot team, with a person reviewing
each reply before it goes out.

Not by Friday: refunds, and every
user. Refunds can follow once we
have read access to your payments
system; I will send a date the
day we get it.

Can you confirm the pilot team
by Tuesday so we can start?

No apology paragraph, no lecture on why a week is short. The free question Reply to a customer’s unrealistic demands has a full framework and model answer.

AI-run screening interviews

Some processes put an AI interviewer before a human interviewer. Candidates for C3 AI FDE roles reported this in August 2026: one described an AI interview invitation followed by a coding round, and another an AI-based screening followed by coding and system design rounds. Source 20C3 AI - Forward Deployed Engineer interview process (comment by u/BalanceOdd144)PublisherReddit r/leetcodeSource typecandidate report on RedditSource 25C3 AI Senior Forward Deployed Engineer (FDE) Interview Process – My Experience (comment by u/speedy_string)PublisherReddit r/OfferEngineeringSource typecandidate report on Reddit In a Reddit thread about C3 AI’s FDE process, one commenter who did not name the company in their own comments said their AI interview “was a blend of both” technical and behavioral questions, with no LeetCode. Source 26C3 AI - Forward Deployed Engineer interview process (comment by u/FickleLingonberry873)PublisherReddit r/leetcodeSource typecandidate report on Reddit The post on C3 AI’s AI screening interview goes through that process in detail.

A related format is the recorded video interview. One poster wrote on Reddit, in September 2026, that they had received a first-round online video interview through Spark Hire for BCG X’s Forward Deployed AI Scientist position. Source 16BCG X R1 Interview help for Forward Deployed AI Engineer (post by u/a_legendary_unicorn)PublisherReddit r/developersIndiaSource typecandidate report on RedditSource 17BCG X interview case (post by u/Classic_Comparison90)PublisherReddit r/McKinsey_BCG_BainSource typecandidate report on RedditSource 18BCG X Forward Deployed AI Scientist Recruiting Process (post by u/Warm-Anything9659)PublisherReddit r/MBB_B4_Tech_RolesSource typecandidate report on RedditSource 19BCG X Forward Deployed AI Engineer live coding round (comment by u/Classic_Comparison90)PublisherReddit r/leetcodeSource typecandidate report on Reddit

What changes when no human is listening:

  • No one rescues a vague answer. A person asks a follow-up; a recorded or automated screen may not. Give the whole answer the first time.
  • Structure carries more weight. Lead with the answer, give one concrete example, end with the result.
  • Technical questions still need specifics. Name the tool, the number you watched and the trade-off you made.

Exact words for a question like “Tell me about a technical project”:

“I built the integration that moved a logistics customer’s order data into our platform. The hard part was their API rate limits, so I added batching and retries with backoff to our Python sync job. I watched the failed-sync count on our dashboard, and within two weeks support stopped escalating sync errors. The customer then expanded the rollout.”

That is a fictional project; use your own. The shape is what matters: what you built, the hard part, what you did, the number you watched, what changed.

This checklist is our method, built for unsupervised timed tests. None of it comes from an employer.

Before you open the link

  • Read the invitation twice: the time limit, the sections, the languages allowed, and the rules on tabs, AI tools and camera.
  • Find out whether the timer starts when you open the link or when you start the first question.
  • Pick one language and stay with it. Know its standard library for strings, sorting, dictionaries and dates.
  • Use a laptop on power, a current browser and a wired or strong connection. Close everything else.
  • If the invitation offers a practice or sample test, take it to learn the editor, the console and how custom input works.
  • Block the time with a margin, in a room where no one will walk in.
  • If anything is unclear, ask the recruiter in writing before you start.

Anthropic’s careers page makes the standard-library point directly: you can look things up, but be comfortable with basic syntax and standard libraries “so it doesn’t eat up your time”. Source 9CareersPublisherAnthropicSource typecompany hiring page

AI tools deserve their own line. Rules differ by company and by stage, and a Salesforce careers post describes an assessment built to show how you use AI. Source 11Ask a Recruiter: How Do I Get AI-Ready Without a Technical Background?PublisherSalesforceSource typecompany blog Never assume either way. The lesson AI rules by company and stage sets out what each employer publishes.

A practice routine for each format

These routines are ours. Run the one that matches the invitation, a few times, before the real link.

Timed algorithm assessment

  1. Set a timer for your test’s length and do two problems, easy then medium, on a platform-style editor with no autocomplete.
  2. Before typing, write the edge cases as comments: empty input, one item, duplicates, huge input.
  3. Submit a working brute force first, then improve it.
  4. Afterward, log where the minutes went.

The free question on the sliding-window rate limiter is a good timed rep; the lesson What FDE coding rounds test sorts which kind of round each employer runs.

Mixed assessment: code, SQL, API, business

  1. One session, one timer, four parts: a data-parsing problem, a SQL query, an API client, and a short written answer.
  2. Do them in the order given, and cap each part at its share of the time.
  3. Write the business answer last and in plain sentences.

Good reps: parse a messy CSV export, find the slowest endpoints by p95 latency, and the SQL and email questions above. For the parsing part, our post on parsing a messy CSV shows how to report what you dropped and why.

Self-paced practical assessment

  1. Treat it like a small ticket: read the whole brief, build a thin working version, then add edge cases and tests.
  2. Leave a short README or comment block stating your assumptions.
  3. Time-box it to the length the invitation gives, and practice on parse a messy CSV export as a self-paced rep, with a README of what you dropped and why.

AI-run or video screen

  1. Write six stories: a project, a customer conflict, a failure, a deadline, a technical trade-off, and why FDE.
  2. Record yourself answering each one on your phone, and play it back.
  3. Cut every answer that does not reach its result quickly.

The closest rehearsal for answering an AI that listens and replies is the free AI practice case: sign in and run it once before your screen.

During the assessment: time, tests and what to submit

  • Budget each question before you start. Read them all, set a per-question stop time, and move on when it passes. The Blind poster who reported on Anthropic’s CodeSignal screen finished the first question with time left and could not finish the second. Source 15Anthropic Solutions Architect/Forward Deployed Engineer CodesignalPublisherBlind (teamblind.com)Source typecandidate report on Blind
  • Run early, run often. A small bug is expensive on a clock. One candidate for a C3 AI FDE role reported on Reddit, in August 2026, that an indentation error they could not find in time ended their process, in a live round. Source 20C3 AI - Forward Deployed Engineer interview process (comment by u/BalanceOdd144)PublisherReddit r/leetcodeSource typecandidate report on Reddit
  • Test the cases the grader might. Visible tests passing tells you little. Add your own custom input for empty, single and malformed cases.
  • Submit code that runs. A solution that passes some tests shows more than one that does not compile.
  • Say what you assumed. A one-line comment on how you handled bad rows or missing fields helps whoever reads your code later.
  • Treat the written part as graded. Nothing published says it is not, and it is the part most like the job. Keep it short and specific.

When it is done, write down every question you remember. The next round may look like it (see the BCG X report above). If you are also wondering how much LeetCode to do, read whether FDE interviews have LeetCode, and for Salesforce, the Agentforce FDE interview.

None of the employers above publishes how its assessment is scored or what score passes, so aim to finish, test and explain. Build a mock OA tonight from the questions below: the messy CSV, the join fan-out, retry with and the customer email, on one timer set to your test’s length. Each has a model answer to check yourself against.

GlossaryForward deployed engineerA software engineer who builds and ships production systems inside a customer’s problem and environment, accountable to that customer’s outcome.More on Forward deployed engineerGlossaryForward deployed software engineerPalantir’s title for its FDE role, called Delta internally; OpenAI and EY also post FDSE titles, each with its own duties.More on Forward deployed software engineerGlossarySolutions architectA customer-facing technical role that designs, advises and often builds proofs of concept; postings place it before the sale, after it, or both.More on Solutions architectGlossaryExponential backoff with jitterRetrying with growing, randomized delays so that clients recovering from the same failure do not retry in lockstep.More on Exponential backoff with jitter

Questions people ask

What do candidates report is on an FDE online assessment?

It depends on the employer. Candidates report coding problems, SQL and API tasks, and one commenter in a Salesforce Agentforce FDE thread described an assessment with a simple coding task, basic SQL, multiple-choice AI questions and an email to a customer with unrealistic demands.Source 1HackerRank forward deployed engineer interview process (comment by u/pranav_india)PublisherReddit r/developersIndiaSource typecandidate report on RedditSource 2HackerRank forward deployed engineer interview process (comment by u/Strange-Egg5496)PublisherReddit r/developersIndiaSource typecandidate report on RedditSource 3HackerRank Forward Deployed Engineer Online Assessment insights? (post by u/ParticularSpirit3387)PublisherReddit r/leetcodeSource typecandidate report on RedditSource 4HackerRank Forward Deployed Engineer Online Assessment insights? (comment by u/ParticularSpirit3387)PublisherReddit r/leetcodeSource typecandidate report on RedditSource 5Palantir FDSE Interview (Blind thread)PublisherBlindSource typecandidate report on BlindSource 6Forward Deployed Engineer (Agentforce) (comment by u/joemons)PublisherReddit r/SalesforceCareersSource typecandidate report on Reddit

Which platforms do FDE online assessments use?

Employers name HackerRank, CodeSignal and CoderPad. Palantir’s early-talent timeline starts with a HackerRank coding challenge, Cresta’s Senior FDE posting describes a self-paced CoderPad assessment, and Anthropic says technical roles use tools such as Colab and CodeSignal.Source 7Students | Palantir Careers (timeline image: RecruitingTimeline_V3.jpg)PublisherPalantirSource typecompany hiring pageSource 8Senior Forward Deployed Engineer (AI Agent)PublisherCresta (Greenhouse job board)Source typecompany job postingSource 9CareersPublisherAnthropicSource typecompany hiring page

What do candidates report about AI-run screening interviews?

Candidates for C3 AI FDE roles reported an AI interview or AI-based screening, an automated interview before a human interviewer, ahead of the coding round. One commenter in a C3 AI FDE thread said theirs mixed technical and behavioral questions.Source 20C3 AI - Forward Deployed Engineer interview process (comment by u/BalanceOdd144)PublisherReddit r/leetcodeSource typecandidate report on RedditSource 25C3 AI Senior Forward Deployed Engineer (FDE) Interview Process – My Experience (comment by u/speedy_string)PublisherReddit r/OfferEngineeringSource typecandidate report on RedditSource 26C3 AI - Forward Deployed Engineer interview process (comment by u/FickleLingonberry873)PublisherReddit r/leetcodeSource typecandidate report on Reddit

Can I use AI tools on an online assessment?

Only if the employer says so. Rules differ by company and by stage, so read the invitation and ask the recruiter when it is unclear. Salesforce’s careers blog, for example, says technical candidates may complete an assessment demonstrating how they use AI.Source 11Ask a Recruiter: How Do I Get AI-Ready Without a Technical Background?PublisherSalesforceSource typecompany blog

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