Plenty of content online explains what a Forward Deployed Engineer (FDE) does. Almost none of it explains how to prepare for the interview — specifically the rounds that trip candidates up most: problem decomposition and client simulation.
This repo is scoped narrowly to those two rounds, on purpose. For system design, take-homes, and behavioral prep, see Resources for Preparation — this guide complements those, it doesn't try to replace them.
- Preparing for LeetCode only: FDE rounds test structured thinking under ambiguity, not algorithm recall.
- Solving before clarifying: Jumping to "I'd build a dashboard" in the first two minutes is the single most common failure mode (see Signal 1 in the Rubric).
- Treating assumptions as facts: Building a plan on an unvalidated premise without flagging it.
- Asserting one "best" answer: No alternatives named, no trade-offs discussed.
- Going silent under pressure: Losing narration exactly when the interviewer adds complexity.
Not raw coding ability — structured thinking, communication under ambiguity, and judgment about real-world constraints (compliance, legacy systems, team capacity).
The 7-Signal Rubric breaks this down concretely across key engineering behavior dimensions.
| Signal | Weak | Adequate | Strong |
|---|---|---|---|
| 1. Clarify before you solve | Proposes a solution in the first 2 minutes | Asks 1–2 questions before solving | Establishes goal, constraints, users, data, and success definition before touching a solution |
| 2. MECE decomposition | Single-dimension or no structure; overlapping sub-problems | Segments along 1–2 dimensions; some gaps remain | Multiple dimensions, mutually exclusive and collectively exhaustive; separates root causes from symptoms |
| 3. Assumption management | Treats assumptions as facts | States 1–2 assumptions when prompted | Proactively labels assumptions, states what changes if each proves false, revisits as new info arrives |
| 4. Trade-off reasoning | Asserts one "best" approach, no alternatives | Names two options, picks one with brief reason | Names 2+ approaches, compares on cost/latency/complexity/maintainability, picks one given this customer's specific constraints |
| 5. Edge cases & failure modes | Designs only for the happy path | Mentions failure modes when asked | Proactively thinks through what breaks each component; fault tolerance is first-class from the start |
| 6. Constraint mapping | Designs in a vacuum — ignores compliance, legacy systems, data residency | Asks about one or two constraints | Maps technical, operational, and business constraints early; names specifics (air-gap, SSO, FedRAMP) unprompted |
| 7. Narration under pressure | Goes silent then delivers a conclusion | Narrates when comfortable, drifts into silence when it gets hard | Maintains coherent narration continuously, even as the interviewer adds complexity |
Note
Weak
- Decomposition round: Ambiguous business problem, no clean answer, evaluated on the 7 signals above.
- Client simulation round: Roleplay with an interviewer acting as a stakeholder/client; rubric coming soon (contributions welcome).
- Not covered here: System design deep-dives, take-homes, pure behavioral — see Resources for Preparation.
A repeatable process for the decomposition round:
- Clarify — Goal, users, constraints, available data
- Decompose — Break the problem into MECE sub-problems
- Prioritize — Pick the highest-leverage sub-problem first
- Propose a phased plan — Not a final static architecture
- Name the risks you're accepting — Explicitly, not implicitly
🎥 See this framework applied in practice
$\rightarrow$ Watch full mock decomposition interview walkthrough
- Structured thinking & communication: Structure is what's being graded, not just the answer.
- Explain why, not just what: Reasoning is the signal, conclusions are secondary.
- Check with the interviewer on direction: This is a working session, not a monologue.
- Call out trade-offs explicitly: Don't let the interviewer infer what you considered and rejected.
Sourced from user interviews with FDEs, aspiring FDEs, and hiring managers:
- "A large hospital system wants to use AI to reduce medication errors. How do you approach this?"
- "A hedge fund wants to use LLMs to improve their research process. Where do you start?"
- "A logistics company's AI dispatch system has been live for 6 months and adoption is at 30%. What's happening and what do you do?"
- "A 50-person fintech startup wants to reduce customer support tickets by 40% using AI. They have 2,000 old support tickets in CSV format. The CEO wants a demo in 2 weeks. You are the FDE."
- "A national logistics company wants to reduce spoilage in its cold chain. Go." (reported from a BCG interview loop)
- "You are at a bank that got a fraud alert. How do you diagnose and resolve it?"
👉 Explore the full question bank with guidance
Stub — contributions welcome.
If you've interviewed at a specific company for an FDE-track role (e.g., Palantir, OpenAI, Anthropic, Scale AI, C3.ai, BCG X), open a Pull Request with anonymized, non-NDA-violating notes on format and focus areas. See CONTRIBUTING.md.
- Simul FDE — Self-paced decomposition & client-simulation interview simulator
- FDE Academy — Cohort-based prep program
- Exponent — General interview prep with some FDE content
- Community threads on Blind and Reddit — Search "forward deployed engineer interview"
- LLMs (Claude, GPT, etc.) can help you rehearse — but verify their answers against real-world constraints rather than memorizing them; interviewers can tell the difference
- Watch: Full mock decomposition interview walkthrough
- System design focus
$\rightarrow$ manjitsin/fde-interview-prep - Broader/general FDE prep
$\rightarrow$ pierpaolo28/Awesome-FDE-Roadmap - Company-specific guides
$\rightarrow$ cma0232/fde-interview-prep
👉 View complete resources reference
This guide reflects patterns observed as of 2026 and will drift over time:
- Varies by region: US and India hiring bars and formats differ.
- Titles are inconsistent: "FDE" is applied loosely across the industry; scope varies by company.
- Roles are still evolving: Expect this content to age — that's what contributions are for.
This resource was put together based on internet research and user interviews with FDEs, aspiring FDEs, and hiring managers. It is not official guidance from any employer.
Open to community contributions — see CONTRIBUTING.md.
Licensed under the MIT License.
Built by Ananth, creator of Simul FDE.