Backend Engineer (Core)

We are building a next-generation financial ecosystem (think NYSE or CME from scratch). As part of Kalshi, you will work on various platforms, including core exchange, clearinghouse, API infrastructure, connectivity to brokers and market makers, and others. We are a small team, which means your responsibilities scale very rapidly, and your contributions are clear and visible, not marginal. There is still a lot of green field at Kalshi and a low of it (including entire systems) can be yours.

Some of the things you’ll be building and working on:

• Order matching and trade execution algorithms and data structures.
• High-performance data feeds and trading APIs for clients.
• High guarantee and availability clearing systems, including margining, collateral management, and banking integrations
• Lead integrations with external market makers, brokers, and hedge funds
• Stress test large-scale critical systems to ensure their robustness and maintainability
• Optimize database access patterns and internal algorithms to improve the performance of our different services
• Design new market structures (e.g., non-binary markets, scalars, futures, etc.)
• Be close to the customer (define features, ship products, iterate)! Even the backend can choose to be close to customers depending on the project.
• Ship fast and with high quality.
• Make decisions: we give a lot of flexibility, which also means no spoon-feeding.

The company is growing fast, which means your role will evolve and grow with the company. Joining Kalshi means you’ll be exposed to all parts of the business and define our culture and product paths.

About You

• 4+ years of software engineering experience.
• Experience planning and leading large projects with long-term impact on a single system or team.
• Strong technical grasp and ability to tackle complex engineering problems that deliver results.
• Solid understanding of relational databases and transactions.
• Familiar with writing highly concurrent systems.
• History of creating and applying new processes and tooling to increase engineering efficiency.
• Excellent judgment on task prioritizations.
• Growth mindset, with a high slope and eagerness to lean
• Love of the craft: you genuinely care and put your all into your work
• Can ship at incredible speed (very simple)

Bonus points

• Experience building financial systems, FIX API, clearing infrastructure, broker connectivity, etc.
• Proven experience building large-scale systems
• Like to interact directly with customers.