To succeed in the Wave interview loop, you must shift your mindset away from typical competitive programming puzzles and toward practical, everyday software engineering. We care about how you organize code, how you handle edge cases, and how you collaborate with peers.

Pragmatic Software Craftsmanship – You must demonstrate the ability to write clean, readable, and well-structured code. This means using sensible variable names, organizing your logic into logical functions or classes, and writing basic unit tests to verify your solution. Avoid over-engineering; a working, simple solution is infinitely better than an incomplete, overly complex one.

System Design & Reliability – When designing systems, focus on real-world constraints such as network latency, database locking, and partial failures. You should be comfortable discussing transactional boundaries, database indexing, and how to make API endpoints idempotent to prevent duplicate transactions.

Collaborative Communication – Our pairing sessions are highly interactive. We do not expect you to work in silence. You should actively talk through your thought process, explain the trade-offs of your decisions, and remain receptive to feedback or hints from your interviewer. Treat the session as a working day with a teammate.

Mission Alignment – Take the time to understand Wave's business model and the unique challenges of operating in our active markets. Be prepared to discuss how your technical decisions can impact end-users who rely on our services for their daily livelihoods.

The interview process for a Software Engineer at Wave is thorough, practical, and highly reflective of how we work on a daily basis. We have structured our pipeline to evaluate your hands-on coding skills, architectural thinking, and team collaboration while minimizing unnecessary academic stress.

The loop typically begins with a conversational screening call with a recruiter to discuss your background, your interest in Wave, and your career expectations. Following this, you will transition into a practical technical evaluation. This consists of a take-home coding assignment where you will build a functional program from a clear specification. Once submitted, you will participate in an intensive, live pair-programming session where you and a Wave engineer will collaborate to extend your take-home code, fixing bugs and adding new features.

After the coding rounds, you will move to a system design interview to discuss architecture and scalability, followed by conversations with engineering leaders, product managers, or founders. These final conversations focus on your past project experiences, your working style, and your alignment with our culture.

The timeline above outlines the typical progression from your first contact to an offer. Most candidates complete the entire technical loop within two to three weeks, depending on their availability for the take-home and pairing stages. We strive to provide fast, transparent feedback at each step of the process.

Practical Coding & Pair Programming

The coding evaluation is the core of our technical assessment. It is designed to simulate a real day of work at Wave, where you are handed an existing codebase or specification and asked to deliver a working solution.

Be ready to go over:

• Environment Setup – Ensuring your local development environment, IDE, and language runtimes (typically Python or JavaScript/TypeScript) are fully configured and ready to run code locally.
• Code Extensibility – Writing modular code during your take-home assignment so that you can easily add new features or modify existing logic during the live pairing session.
• Testing & Debugging – Writing simple tests to validate your code and demonstrating structured debugging skills when things do not work as expected.
• Advanced concepts (less common) – Optimizing time complexity for recursive operations (e.g., cell dependency resolution), handling complex string parsing, and implementing custom event emitters.

Example scenarios:

• "You have built a basic spreadsheet engine. Now, let's extend it to support cell ranges (e.g., SUM(A1:B3)) and handle circular dependency detection gracefully."
• "Using the API game engine you built, let's write a set of tests to verify that a player cannot make a move out of turn, and then implement a feature that saves and resumes game states."

System Architecture & Design

In this round, we want to see how you approach building large-scale, distributed systems. We focus on practical trade-offs, data modeling, and system reliability under real-world constraints.

Be ready to go over:

• Data Consistency – Understanding how to design databases and transactional flows that prevent data corruption, double-spending, or race conditions.
• API Design – Creating clean, intuitive, and robust APIs that handle mobile client constraints, such as intermittent connectivity.
• Scalability & Bottlenecks – Identifying system bottlenecks (e.g., database locks, slow third-party APIs) and explaining how to mitigate them using caching, queues, or asynchronous workers.
• Advanced concepts (less common) – Eventual consistency patterns, distributed locking mechanisms, and database sharding strategies.

Example scenarios:

• "Design a ledger system for a mobile money platform that can handle 10,000 transactions per second while ensuring that no user's balance ever drops below zero."
• "How would you design an alert and retry mechanism for a system that relies on an unstable third-party banking API to process merchant payouts?"

Collaboration, Values & Culture Fit

At Wave, how you work is just as important as what you build. We look for engineers who are collaborative, humble, highly autonomous, and deeply aligned with our mission of reducing financial transaction costs.

Be ready to go over:

• Receiving Feedback – How you react when an interviewer points out an edge case you missed or suggests an alternative implementation path.
• Pragmatic Decision Making – Explaining how you balance technical debt with shipping product value to users quickly.
• Cross-Functional Communication – Demonstrating your ability to explain technical concepts clearly to product managers, operations teams, and non-technical stakeholders.

Example scenarios:

• "Describe a time when you had to support a legacy system that was poorly documented. How did you manage to maintain it while building new features?"
• "How do you prioritize your engineering work when you are faced with competing demands from product, operations, and technical debt refactoring?"