Software Engineer, Backend Systems

Software Engineer, Backend Systems

Company: Fullstack
Location: San Francisco, CA - on-site, 5 days per week
Compensation: $185,000 - $300,000 base (based on qualifications and experience) + competitive equity
Employment Type: Full-time

About Fullstack

Fullstack is building a single front end for crypto trading. Today, retail traders are spread across multiple trading front ends, browser-extension wallets, bridges and a growing list of new venues every year, which makes trading confusing and risky for new users. Fullstack brings every product a trader wants, including perpetuals, cross-chain spot and prediction markets, into one portfolio-margin trading experience with a single unified balance.

Under the hood, users post collateral on Fullstack's systems and Fullstack extends USDC collateral to the venues of their choice, bringing the venues to the user instead of the other way around. Users will be able to post multiple forms of collateral and trade on venues such as Hyperliquid without selling down their holdings.

The founding team comes from the center of crypto trading infrastructure. One co-founder built Insilico Terminal, which the company describes as the leading order execution and management system for centralized exchanges, with more than $900B in retail trading volume. The other ran one of the top on-chain and centralized-exchange high-frequency trading firms and brings deep experience engineering low-latency systems. Fullstack has raised $15M+ and has a team of about 10, with offices in San Francisco and New York.

The Role

Fullstack is looking for a backend engineer with production Rust experience to help build the infrastructure behind its real-time trading platform. You will work on the systems that carry the most weight in the product: risk, settlement, market data and the APIs traders depend on. This role suits someone with a strong command of asynchronous programming, solid systems knowledge and a performance-driven mindset who thrives in a high-bandwidth, collaborative, in-person environment.

What You Will Do

• Build and maintain risk and liquidation engines that manage risk and improve capital efficiency in volatile markets.
• Design and implement the blockchain state machines that power trading, settlement and risk operations.
• Develop services that keep state consistent across asynchronous processes using voting, consensus and coordination mechanisms.
• Process live market data and coordinate actions across trading venues, managing WebSocket streams and time-sensitive workflows.
• Build high-performance REST and WebSocket APIs that power the trading interface with millisecond-level response times.

What You Bring

• 2-4 years of experience as a backend software engineer
• In-depth, production experience with Rust
• Strong command of asynchronous programming (Tokio experience is a plus) and distributed systems
• A performance-driven mindset and comfort with latency-sensitive, real-time systems
• Ability to work on-site in San Francisco 5 days per week
• Work authorization: Fullstack can support TN visas and H-1B transfers only (excluding H-1B holders in year 3 or year 6). Candidates who do not need sponsorship are also welcome.

Tech Stack

Rust, Tokio, distributed systems, blockchain, REST APIs, WebSocket APIs, Docker