ROUND 2

Interviewer Intel

Deep profiles on your interviewers. Understand who they are, what they care about, and how to position yourself for each conversation.

ROUND 2 CONTEXT

FORMAT: Technical deep-dive with two interviewers. Mattia assesses product/culture fit. Milan validates engineering depth.
KEY INSIGHT: They already like you from Round 1. This round is about proving you can build at production scale and think like an owner.

Mattia Astarita

BD / Partnerships / Solutions Lead

Background

  • · One of the earliest Gnosis Pay employees — helped build it from scratch
  • · Background in aerospace engineering (CubeSat sensors at Raytheon, ADCS team for HELIOS III satellite)
  • · Solutions Engineer at OneWeb (LEO satellite connectivity)
  • · Presented at Imperial College London on satellite infrastructure
  • · Posts jobs for operations roles — has hiring/leadership authority
  • · Public face at industry events (EthCC, Gnosis ecosystem)
  • · Works with banks, Web3 wallets, on/off ramps, and NGO institutions
  • · Celebrated $105M payment milestone — deeply connected to the product vision

Likely Question Areas

  • DEEPGnosis Pay self-custody model vs custodial competitors (Crypto.com, Coinbase Card)
  • DEEPB2B2C platform design — how would fintechs integrate Gnosis Pay's infrastructure?
  • DEEPExplaining Zodiac modules (Roles + Delay) to non-technical partners
  • MODERATEWhy the 3-minute delay exists at the payment rail level
  • MODERATEStablecoin settlement flow — Monerium IBANs, Visa T+1
  • MODERATEERC-4337 vs Safe modules — what Gnosis Pay actually uses and why
  • MODERATEPartner API design — authentication (SIWE), webhooks, sandbox environments
  • SURFACEGnosis 3.0 vision — Safe + Gnosis Pay + CoW Swap unification
  • SURFACERegulatory/compliance context — MiCA, KYC flow, card program licensing

Strategy

  • ▸ Lead with product empathy — show you understand WHY decisions were made, not just WHAT was built
  • ▸ Frame technical answers in business outcomes: 'This architecture enables X for partners'
  • ▸ Demonstrate you can be the bridge between engineering and BD/partnerships
  • ▸ Show ecosystem knowledge — mention specific Gnosis ecosystem projects (CoW, Safe, Karpatkey)
  • ▸ Reference the $105M milestone and what it takes to scale from there

Watch Out

  • ! Don't go too deep into implementation details unless asked — he values clarity over depth
  • ! Don't ignore the business context — every technical choice has a partner/user impact
  • ! Don't be dismissive of non-technical stakeholders — his job is working with them
  • ! Don't forget he's assessing cultural fit as much as technical knowledge

Strength Signals

  • + Reference specific Gnosis Pay architecture details (Roles Module scoping, Delay Module queue, Gelato 1Balance)
  • + Show you think about partner experience, not just code
  • + Mention specific stablecoins (EURe by Monerium, USDCe via Circle bridge)
  • + Discuss the Gnosis 3.0 convergence (Safe wallet + Pay + CoW Swap)
  • + Frame self-custody as a competitive moat, not just a technical choice

Opening Moves — Things to Say Early

"I've studied the Gnosis Pay architecture closely — the self-custody model with Safe + Zodiac modules is elegant because it gives users real ownership while enabling card-grade UX."
"What excites me about the B2B2C direction is that the same infrastructure that powers the direct card can become a platform — the Roles Module already provides per-partner scoping."
"I've operated treasury infrastructure with real money on Gnosis Chain, so I understand the stakes of production systems handling user funds."

Milan Pajovic

Senior Backend Engineer / Tech Lead

Background

  • · Self-describes as 'Senior Backend Engineer | Tech Lead working on Blockchain products'
  • · Co-founded Bizzllet — self-custody business crypto wallet built on Account Abstraction + MPC
  • · Bizzllet was a venture from web3 venture builder Attic42 (Belgrade, Serbia)
  • · GitHub: 3 public repos — all TypeScript: SIWE app, swap-event-parser, customized-token-list
  • · His SIWE repo shows deep understanding of EVM-based authentication
  • · swap-event-parser shows event-driven blockchain data processing expertise
  • · Active in the intersection of traditional backend engineering and blockchain

Likely Question Areas

  • DEEPDistributed systems: idempotent payment APIs, exactly-once delivery, saga patterns
  • DEEPAccount Abstraction: ERC-4337 architecture, Safe modules, bundlers, paymasters
  • DEEPSIWE (Sign-In with Ethereum): nonce handling, session management, JWT issuance
  • DEEPEvent-driven architecture: indexing on-chain events, reorg handling, at-least-once guarantees
  • DEEPGo patterns: goroutines, channels, context cancellation, error wrapping, interfaces
  • DEEPTypeScript to Go migration: strategies, type mapping, concurrent patterns
  • DEEPDomain-Driven Design: bounded contexts, aggregates, domain events in payments
  • MODERATEDatabase design: transaction isolation, optimistic locking, nonce management in Postgres
  • MODERATERelayer/meta-transaction architecture: gas management, Gelato Relay, ERC-2771
  • MODERATETesting: table-driven Go tests, testcontainers, Foundry fuzz/invariant testing
  • MODERATEMPC (Multi-Party Computation) for key management — from his Bizzllet experience
  • MODERATEProduction reliability: circuit breakers, graceful degradation, observability

Strategy

  • ▸ Lead with depth — Milan is a builder, he wants to see you can architect and implement
  • ▸ Show Go fluency even if your primary language is TypeScript — they're actively migrating
  • ▸ Demonstrate you think about failure modes FIRST, happy path second
  • ▸ Use his open-source repos as common ground — SIWE and event parsing are things you both know
  • ▸ Show production battle scars — real incidents you've handled, not textbook answers

Watch Out

  • ! He WILL go deep on implementation details — vague answers won't fly
  • ! He co-founded an AA+MPC company — he knows Account Abstraction inside out
  • ! He reads candidates' GitHub before interviews (Glassdoor intel) — be ready to discuss your code
  • ! Don't pretend to know Go deeply if you don't — better to show you're learning fast with concrete examples
  • ! Don't give junior-level answers like 'I'd just add a retry' — he wants to hear about backoff, circuit breakers, dead letter queues

Strength Signals

  • + Discuss nonce management strategies (DB-backed locks, sequential queues per address)
  • + Explain exactly-once delivery in payment systems (idempotency keys + deduplication table)
  • + Walk through Safe module internals: Roles v2 scoping, Delay Module queue mechanics
  • + Show Go code patterns: context propagation, interface-based mocking, table-driven tests
  • + Discuss reorg handling in event indexers (parent hash comparison, rollback + replay)
  • + Explain MPC vs multisig tradeoffs for key management (from his Bizzllet context)
  • + Demonstrate DDD modeling: Payment aggregate, Money value object, domain events

Opening Moves — Things to Say Early

"I've been studying the Safe module architecture — the way Roles Module scopes permissions per function selector is brilliant for payment systems because it gives you programmatic spending limits without per-tx signatures."
"I noticed your SIWE implementation on GitHub — I've been working with EIP-4361 for auth flows and I'm curious how Gnosis Pay handles session management with the JWT tokens."
"My background is TypeScript-heavy but I've been writing Go for [X] — the explicit error handling and goroutine patterns are a good fit for payment processing where you need to handle every failure case."

Overall Battle Plan

First 5 Minutes

  • ▸ Open with enthusiasm about the self-custody card model
  • ▸ Reference specific architecture: Safe + Roles + Delay modules
  • ▸ Show you've done your homework on the B2B2C transition
  • ▸ Mention your production experience with real money on Gnosis Chain
  • ▸ Frame yourself as 'protocol-aware backend engineer who understands financial risk'

Things to Avoid

  • ✕ Don't describe vanilla ERC-4337 without knowing GP uses Safe + Gelato
  • ✕ Don't give shallow answers to Milan — he will probe deeper
  • ✕ Don't oversell frontend skills — this is a backend/protocol role
  • ✕ Don't forget to ask THEM questions — shows genuine interest
  • ✕ Don't rush through answers — think out loud, show your reasoning process

Questions FOR Mattia

  • "How are partners currently integrating with the Gnosis Pay API?"
  • "What's the biggest challenge in the B2B2C transition?"
  • "How does the team handle the tension between self-custody and compliance?"

Questions FOR Milan

  • "How far along is the Go migration? What drove the decision?"
  • "What does the on-call/incident response look like for the payment system?"
  • "How do you handle reorgs in production — have you had any close calls?"

Questions FOR Both

  • "What does the team structure look like for the B2B2C build?"
  • "What's the hardest production incident the team has dealt with?"
  • "Where do you see Gnosis Pay in 2 years?"