Software Engineer (Java Generalist)

Software Engineer (Java Generalist)

Location: US - Open to Europe if happy to overlap with EST

Compensation: $160K - $200K

Our firm has been retained by a high-growth, mission-driven technology company to find a world-class Principal Java Systems Engineer. This is not a role for "glue" engineers who connect off-the-shelf components; this is for the engineer who sees performance ceilings as a personal challenge and prefers squeezing 30% more throughput out of clean Java over renting 30% more cloud compute.

Our client is building a high-performance, publicly visible immutable ledger. In an industry where people "move fast and break things," this team operates like NASA: moving fast while ensuring correctness, performance, and efficiency are 100% right the first time. You will join an elite team where you aren't a cog in the machine—you are the architect building it.

Key Responsibilities:

• First-Principles Engineering: Invent new protocols, data structures, and algorithms to solve problems no one else has tackled.
• Low-Latency Systems: Design and write high-throughput Java systems from scratch, tuning memory down to the byte and performance to the nanosecond.
• Core Infrastructure: Build parsers, interpreters, and performance profilers from the ground up.
• Technical Leadership: Mentor senior and staff engineers while making architectural decisions that ensure the correctness of a global ledger.
• Optimization: Switch fluently between high-level system design and single-instruction-level optimization.
• Rigorous Testing: Build harnesses and tests to ensure mission-critical financial software never breaks.

Requirements

• Experience: 10+ years of professional software development experience.
• JVM Mastery: Deep understanding of the JVM, including memory models, threading, GC behavior, and performance profiling.
• Systems Background: Experience with parsers, interpreters, compilers, or other language tooling.
• CS Fundamentals: Strong grasp of data structures, algorithms, concurrency, and high-performance code with minimal dependencies.
• Proven Delivery: Ability to deliver a high-performance server from scratch using just the JDK and an IDE.
• Tooling: Proficient with JMH, PBJ, async-profiler, JFR, YourKit, or similar performance tools.
• Education: Master’s degree in Computer Science or equivalent deep industry experience.

Preferred Good-to-Have Skills:

• Experience in distributed systems or blockchain technology.
• Knowledge of cryptographic primitives (hashes, public/private keys).
• Familiarity with Web3 tools, smart contract platforms (EVM), or high-frequency trading (HFT) systems.

Benefits

• Career-Defining Impact: Build the foundational infrastructure for the next generation of the digital economy.
• Technical Autonomy: Work on a small team with high ownership and the freedom to craft brilliant systems "the right way."
• Intellectual Challenge: Solve puzzles that require deep-stack engineering knowledge rather than standard API integration.
• Professional Growth: Mentorship from and for some of the best minds in distributed systems.
• Compensation: Highly competitive salary and equity packages reflecting the "Principal" level of this role.

Due to the high volume of applications we anticipate, we regret that we are unable to provide individual feedback to all candidates. If you do not hear back from us within 4 weeks of your application, please assume that you have not been successful on this occasion. We genuinely appreciate your interest and wish you the best in your job search.

Commitment to Equality and Accessibility:

At MLabs, we are committed to offer equal opportunities to all candidates. We ensure no discrimination, accessible job adverts, and providing information in accessible formats. Our goal is to foster a diverse, inclusive workplace with equal opportunities for all. If you need any reasonable adjustments during any part of the hiring process or you would like to see the job-advert in an accessible format please let us know at the earliest opportunity by emailing human-resources@mlabs.city.

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