Day-Of Tactics

Pre-loop checklist

• Sleep. Caffeine to taste, not heroically.
• Reread 01-the-role and your own positioning script from 02.
• Scan 14-domain-context — vocabulary refresh, 10 minutes.
• Re-run drill on 3-5 questions from 15 out loud.
• Have your two corridors picked (e.g. "UK FPS + Brazil PIX"). Don't claim more.
• Have one production story queued — a real product decision you owned; metric, tradeoff, outcome.
• Have one halt-the-launch / partner-conflict story queued.
• Have 3-5 thoughtful questions for the interviewer (see below).
• Water nearby. Whiteboard tool open. Editor warmed up.

The default structural frame for a design round

When the interviewer asks a payments product question, default to this skeleton out loud:

1. Clarify the rail and the market.
2. Quantify the opportunity.
3. Cost stack.
4. Vendor strategy.
5. KPIs.
6. Risks & compliance.
7. Rollout.

You don't have to spend equal time on each; the interviewer will steer. But explicitly naming the skeleton up front is itself a signal — it tells the interviewer "I have a framework, we can probe deep where you want."

Always clarify rail + market before designing

"Design a deposit flow" is too vague. Always pin down:

• Which market — what's the dominant local rail, regulator, customer behaviour?
• Which rail — card? Bank push? Open Banking? Wallet? Multiple?
• Which user type — first-time consumer, returning Pro, institutional partner?
• Which surface — Consumer app, Pro, Krak, on-ramp API?

Two clarifying questions, max. Then proceed. Endless clarification reads as stalling.

Quantify the opportunity

Give it a Fermi estimate quickly. "Brazil has ~100M adults online; assume 5% have ever bought crypto; assume X get to the company; assume Y deposits/month at Z avg ticket; that's $W TPV/month." Sloppy is fine. Refuse the temptation to be precise. The interviewer wants to see you reach for numbers comfortably.

Bring the cost stack

"Card all-in cost ~2-3%, PIX ~30-50bps, UPI lower still." Naming the cost stack proves you're thinking like a payments PM and not a generic product PM. Cite all-in: interchange + scheme + cross-border + FX + acquirer + PSP + chargeback. Don't be exact.

Vendor strategy in every answer

"For this rail in this market, I'd want at least two viable PSPs, RFP-selected, with cascading rules and a quarterly business-review cadence." This sentence — or some version of it — should appear in every design round. The role description literally uses the words "vendor-dependent environment."

Name the KPIs

Pick the right 2-3 for the question. For an on-ramp launch: conversion intent→success, AAR, cost-per-success. For a retry policy: first-attempt AAR vs final AAR + cost-per-success. For 3DS UX: completion-given-auth, fraud bps. Always name guardrails too — fraud rate, support contacts, chargeback rate.

Risks & compliance early, not at the end

"Compliance partner from day one" is a senior tell. Mention AML monitoring overlay, sanctions screening, Travel Rule (if crypto-adjacent), and licensing in the first half of any design — not as a footnote.

Show the rollout

Don't end at "ship it." Sketch the rollout: canary → whitelist → 1% → 5% → 25% → 50% → 100%, with gate criteria. Mention hypercare. Mention the dashboard you'd build before launch. Mention what you'd watch in the first 72 hours.

Traps to avoid

Questions to ask them

Bring 5; use 2-3. Tailored, not generic:

1. "Which corridor in the current portfolio is the highest-leverage in the next 6 months, and what's currently blocking it?"
2. "What's the AAR baseline you'd hand a new PM on day one, and how confident is the team in the measurement?"
3. "How does the team currently split work between this PM seat and the payments-engineering tech leads? Where's the friction?"
4. "When was the last time you de-platformed a PSP, and what triggered it?"
5. "For a new rail launch in a new market, what's your typical timeline from RFP to first production payment?"
6. "What's the most ambiguous compliance call the team has had to make in the last year?"
7. "How is Krak's payments roadmap interacting with the company's? What's shared, what's separate?"

Closing

Two final beats:

• Be specific about what you bring. One sentence — vocabulary you've earned, judgement you've earned, motivation. Not a pitch; a recap.
• Say what you're excited about. Name one thing they said in the loop that landed for you. "What you said about the on-ramp friction in [market] — that's the kind of problem I want my next decade in."

Good luck.