About OpenCoreOS

• We're building the first open-source "Thin Ledger", designed to replace legacy core systems with a Golang-based, Protobuf-defined, event-driven platform powered by Kafka, Redis, and multi-region CockroachDB/YugabyteDB.
• Our platform is AI-native from the ground up: autonomous SRE agents, AI-generated runbooks, and everything-as-code—from policies to infrastructure definitions.
• We're mission-critical by default, targeting five-nines uptime and multi-region failover for regulated institutions.
• We work openly and fast, and colocate in Huckletree, Liverpool St, London for in-person collaboration, supported by async-friendly workflows.

What you'll do 🚀

The Core Ledger Engine

• Implement distributed consensus for replicated state across nodes
• Design deterministic state machines where identical inputs always produce identical outputs
• Build two-phase commit protocols for complex multi-party settlements
• Create type-safe financial primitives that make entire classes of bugs impossible
• Optimize hot paths for microsecond latency with cache-aware data structures ️

Transaction Processing

• Architect atomic transaction chains (linked transfers that all succeed or all fail)
• Implement checkpoint/rollback semantics for complex financial workflows
• Build idempotency guarantees for exactly-once processing in distributed environments
• Design constraint systems for balance validation that never permits overdrafts or invalid states ️

High-Performance IO & Networking

• Design storage engines using direct IO and modern kernel interfaces for predictable latency
• Implement zero-copy networking paths to minimize memory bandwidth overhead
• Build async IO subsystems that saturate hardware without blocking consensus
• Optimize for kernel bypass and minimizing syscall overhead on critical paths

⚡ Build next-gen infrastructure Systems Engineer 2

• Support multi-cloud deployment with consensus-based failover
• Build observability and audit systems for regulatory compliance
• Create tooling for deterministic replay and debugging of production issues

Who you are

• Systems programmer at heart. You understand memory layouts, cache lines, and why allocation on the hot path matters.
• Distributed systems practitioner. You know the difference between Raft and Paxos, understand why linearizability matters, and have opinions on consensus protocol trade-offs.
• Correctness-obsessed. You write code that handles every edge case. You think about invariants, prove properties, and design systems that are correct by construction.
• Low-level thinker. You're comfortable reasoning about concurrency without locks, understanding why single-threaded event loops can outperform multithreaded alternatives, and optimizing for predictable latency.
• Security mindset: Understanding of secure coding practices and experience with high compliance systems
• Ownership mindset: You thrive on autonomy, figure things out proactively, and excel at thoughtful prioritization
• Exceptional communicator: Skilled at translating technical concepts across teams
• AI-native engineer: You naturally integrate AI into your workflow—actively using advanced AI tools

Nice-to-haves

• Fintech experience: Knowledge of financial transaction flows or HFT / T1 core banking
• Systems programming language experience: Low-latency systems built using Rust

Why join us?

• Massive impact: Transform how T1 banks handle billions of transactions daily—on a truly open platform.
• High-caliber team: Join a small team of exceptional engineers who value both speed and stability.
• AI-native workspace: Experience an AI-first environment with LLMs integrated into every tool.