Quantitative Developer - Risk

**Ellipsis Labs** Quantitative Developer - Risk; $180K–$250K base + equity; New York City (In-person)

**About Company** 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.

**About the Role** Ellipsis Labs is looking for a Quantitative Developer to join its Risk team. This is a platform-wide role: the team owns solvency, margin, and liquidation systems across all Ellipsis products. The person in this seat will design, build, and maintain the numerical engines that enforce margin requirements, trigger liquidations, and keep the exchange solvent during periods of extreme volatility. Compared to the prior Senior Backend Engineer (Risk Engineering) posting, this role has a lower experience bar, broader scope, and a quant-developer profile rather than a pure backend-engineering one.

**Responsibilities** - Design, build, and maintain risk infrastructure: margin engines, liquidation systems, and solvency monitors across all Ellipsis products. - Develop quantitative models for risk assessment, pricing, and portfolio analysis in DeFi markets. - Build low-level, performance-critical systems that keep the exchange solvent during high volatility and liquidity stress. - Own initiatives end-to-end, from research and design through launch and ongoing reliability. - Monitor system performance at micro- and nano-second granularity. - Collaborate closely with engineering and leadership in a fast-moving startup environment.

**Required Skills** A. 3+ years of experience preferred; exceptional new grads with strong quantitative backgrounds are also eligible. B. Strong quantitative/mathematical foundation, through a quant role, a math/stats/physics degree, or equivalent experience. C. Proficiency in at least one systems-level language: Rust, C++, C, Go, Python, or TypeScript. D. Demonstrated ability to architect and own complex numerical projects independently.

**Bonus Skills** - Experience working with blockchain technology, specifically Solana. - Proficiency in Rust or strong interest in building in Rust. - Experience building liquidation systems, risk engines, or margin call systems. - Familiarity with pre-IPO or private market funding structures. - Background in TradFi trading, HFT, or crypto exchanges.

**Logistical Info** - Location: New York City, in-person 4 days/week (Monday, Tuesday, Thursday, Friday; Wednesday optional WFH). Office at 120 Fifth Avenue, Floor 7. - Compensation: $180K–$250K base + equity. - Number of openings: 1 - **Other:** Visa sponsorship: H-1B transfers and Canadian TN visas (carried over from the prior posting for this req; to be reconfirmed).

**Ideal Background** - Quantitative developers, risk engineers, or trading systems engineers from HFT/quant firms: Jane Street, Citadel, Two Sigma, HRT, IMC, DRW, Jump Trading, Tower Research, Virtu. - Strong academic pedigree — top-20 CS, math, physics, or stats programs. - Crypto exchange engineers (Coinbase, Kraken, Binance, dYdX) with quantitative depth. - Exceptional new grads from top programs with demonstrated quant ability (competition math, research, strong internships). - High career velocity — upward trajectory in responsibility or caliber of company. - Recruiter note (unconfirmed — confirm with Brian before screening): (1) are PhDs still a red flag on this reframed posting, they were on the prior Senior Backend Engineer (Risk Engineering) req; (2) is the interview process unchanged from the prior req; (3) how important is "familiarity with pre-IPO or private market funding structures" from the Ashby posting; (4) any change to visa sponsorship policy.

**Green Flags** - Quant developer at a tier-1 quant fund or HFT firm. - Strong quantitative/math background — quant dev role, math/stats degree, or numerical systems work. - Deep understanding of liquidations, margin calls, or risk systems. - Top-20 school in CS, math, physics, or stats. - High career velocity. - Passion for DeFi, even without direct crypto experience. - Exceptional new grad with competition math, published research, or strong internship pedigree.

**Red Flags** - Jumpy background — short stints across multiple companies. - No sign of quantitative/math ability. - Banks or prime brokerage background — do not source from this segment. - Flat career trajectory. - Gemini engineers have consistently underperformed in technical screens. - Bearish on: Bullish, Crypto.com, Blockchain.com (not an immediate no, use caution). - General web backend or ML experience alone is not sufficient. - Resumes led by a laundry list of tech-stack keywords rather than ownership and impact. - Market data engineers. - Non-trading risk experience (must be trading risk: liquidations, margin calls, exchange solvency, or quantitative modeling).

**Interview Process** 1. Intro call with Brian — assesses strongest language and matches next interview accordingly. 2. Technical phone screen (CoderPad, algorithm problem). 3. Optional take-home project, if needed based on phone screen. 4. Onsite: three technical rounds (bug squash in C++, Python, Rust, or TypeScript; system design; another coding round), behavioral interview with CEO, lunch with team.