Sr. Backend Engineer II - US Stocks

Founded to transform retail finance, Ajaib Group is an Indonesian fintech unicorn breaking barriers to financial access. Having recently secured a $270M Series C—the single largest funding round in Southeast Asia over the past four years—we are backed by premier global investors including Y Combinator, Ribbit Capital, SoftBank, and SBI Holdings. To build world-class products, we assemble world-class talent. Supported by our fully remote work arrangement, our team spans Eastern Europe, the Middle East, India, and Southeast Asia, allowing you to work with brilliant engineers and builders from around the globe from wherever you are. We operate with an impact-driven purpose where everyone is the owner of our customers' satisfaction. Driven by a growth mindset and a fierce will to win, we refuse to settle and constantly push engineering boundaries. Role Overview As a Sr. Backend Engineer II in the US Stocks team, you own backend services for trading US stocks from design to production: order flow to our brokerage partners, balances and currency conversion, market data, portfolio and corporate actions. You take on larger and more complex features, make sound design decisions under real traffic, and mentor engineers around you. Design, build and run scalable, secure backend services and APIs for trading, funding, market data and portfolio features. Own larger features and services end to end, including monitoring, alerting and on-call follow-up. Design for correctness first: accurate money and quantity handling, idempotent requests, safe retries and audit trails. Integrate with US brokerage and custody partners, and make those integrations resilient to outages, delays and duplicate or out-of-order messages. Build and improve reconciliation between our records and our partners' records, and drive root-cause fixes for mismatches. Handle US-specific events correctly, such as market hours, dividends, stock splits and settlement timing. Keep services fast and stable at US market open and during volatile days, and plan capacity ahead of known events. Lead design reviews and give thoughtful code reviews. Investigate production incidents, run root cause analysis and ship lasting fixes. Mentor mid-level engineers and share knowledge within the team. Design resilient, low-latency order routing logic to manage execution across multiple Liquidity Providers (LPs) and venues, handling rate limits, partial fills, and complex order lifecycles. Proactively identify systemic risks across the US Stocks domain and propose architectural improvements, acting as a technical bridge to Staff engineers.