Senior Backend Engineer (Risk Engineering)

Ellipsis Labs is a profitable, venture-backed New York-based startup building differentiated products and infrastructure in decentralized finance. The company is the developer of Phoenix, the leading order book spot exchange on the Solana blockchain, and a top 10 DEX (decentralized exchange) with >$70B in volume since inception in 2023. Additionally, we are one of the most active and prominent on-chain market makers in crypto.

Ellipsis Labs seeks a Senior Backend Engineer to join the Risk Engineering team. This team builds and maintains the liquidation engines that enforce solvency on our perpetual futures (perp) exchange. The role involves designing low-level systems that perform numerical calculations to trigger user liquidations when margin thresholds are breached, ensuring the exchange remains solvent during periods of high volatility.

We are looking for a staff-level engineer (5–10+ years of experience) who can architect systems end-to-end, lead complex numerical projects independently, and bring deep domain knowledge from either traditional finance trading or crypto. Web3 experience is NOT required, but either TradFi or crypto experience IS required.

• →Build and maintain liquidation engines for our perpetual futures exchange, enforcing numerical calculations that trigger liquidations when a user's margin is breached.
• →Design low-level, performance-critical systems that keep the exchange solvent during periods of high market volatility and liquidity stress.
• →Own initiatives from design through launch and ongoing reliability, collaborating closely with engineering and leadership.
• →Monitor system performance at micro- and nano-second granularity.
• →Adapt to fast-changing requirements and shipping cycles in a startup context.

7+ years of experience building and maintaining production-grade software systems with low-level skills (preferably in Rust, C++, C, Golang, Python, TypeScript).

Staff-level seniority: proven ability to lead projects, architect systems end-to-end, and operate independently on complex work.

Domain experience (one required): Either (a) TradFi trading background with strong understanding of markets, margin trading, and margin calls; OR (b) crypto background with specific knowledge of liquidations (does not need to have built a liquidation system, but must have thought deeply about them).

Quantitative / math background: The work is statistical and numerical in nature. Candidates must demonstrate strong math ability - whether through a quant dev role, a math/stats/physics degree, or equivalent quantitative experience.

• Experience working with blockchain technology, specifically Solana
• Proficiency in Rust or interest in building in Rust
• Experience building liquidation systems, risk engines, or margin call systems
• Interest in DeFi and trading systems (passion not required, but intellectual curiosity is valued)