Software Engineer, Data Core

Flow Traders

Flow Traders is looking for a Senior C++ Software Engineer to lead the next-generation architecture of the market data and execution platforms that power our fully systematic trading. We don't treat market data as plumbing - for us it's a source of alpha, where feed handling, order book construction, and a deep understanding of exchange microstructure are themselves a competitive edge. We're looking for a senior individual contributor who has lived this philosophy in a proprietary or systematic trading environment and can squeeze every nanosecond out of the path from wire to strategy. As a senior individual contributor, you'll help set the technical direction for the Core Platform that underpins quantitative research, pricing, strategy development, and execution across hundreds of venues - and drive its global rollout across our Market Data, Quant Research, Pricing, and Strategies groups. You'll work in a tight, iterative loop with quants and technical traders, applying deep expertise in modern C++, OS internals, CPU and memory architecture, lock-free concurrency, and low-latency networking to push our systems toward state-of-the-art performance, robustness, and observability.   WHAT YOU WILL DO: * Lead the development and global rollout of our Core market data platform used across multiple focus areas (Market data, Research engineering, Pricing, Strategies). * Design and implement high‑performance components for market data ingestion, normalization, and distribution, as well as its usage for order execution and strategy infrastructure. * Develop tools and frameworks that enable quants and technical traders to build, tune, and deploy data‑driven systematic pricing and trading strategies. * Own the full lifecycle of your components in a fast‑paced, iterative environment: deploy, monitor, profile, and optimize your code in production. * Work closely with focus group engineers, quants, and technical traders to refine requirements, collect feedback, and iterate on the platform's design and implementation.   WHAT YOU NEED TO SUCCEED: * BSc, MSc, or PhD in Computer Science, Mathematics, or a related field. * 7+ years of post‑graduation professional C++ software development experience. * Experience building low‑latency market data ingestion, order execution, and algorithmic trading systems (proprietary trading industry preferred). * Strong knowledge of algorithms and data structures. * Experience in parallel, asynchronous, and multithreaded programming. * Demonstrated ability to write clean, reliable, and highly scalable C++ code. * Interest in extracting maximum performance from available hardware and software (CPU caches, memory layout, networking, etc.). * Ability to communicate effectively with both technical and non‑technical colleagues.   Flow Traders does not accept unsolicited resumes from any professional staffing or search firms. All resumes, and any other information identifying potential candidates, submitted to any employee at Flow Traders via email, the Internet or directly without a valid and signed search agreement will be deemed free to contact by Flow Traders without any restrictions and no placement fee of any kind will be paid in the event the candidate is hired by Flow Traders

Ledgy

At Ledgy, we’re on a mission to make Europe a powerhouse of entrepreneurship by building a modern, tech-driven equity management and financial reporting platform for private and public companies. In 2026, we aim to be the leading provider for European IPOs and reporting for share-based payments. We are a value-based company with a core focus on being humble, transparent, ambitious and impactful, all in order to delivery the best experience for our customers and end users. We are proud to partner with some of the world’s leading investors. New Enterprise Associates led our $22m Series B round in 2022, with Philip Chopin joining Sequoia’s Luciana Lixandru on our board. We were founded in Switzerland in 2017 and today we operate globally from offices in Zurich and London. We encourage diversity and are an international team coming from 26 different countries and speaking 25 different languages.   About the Role As a Senior/Staff Software Engineer at Ledgy, you’ll design and build elegant, scalable systems that power how companies manage their equity. You’ll collaborate with fellow engineers (based mainly in Zurich and London), product managers, and designers to develop industry-leading automation and experiences — while many in our space still rely on manual processes. In the first 30 days: * Be paired with an onboarding buddy who will introduce you to the world of equity management * Get to know our engineering team, product managers, and designers * Understand how your team’s surface area connects to the broader Ledgy platform * Start contributing to the codebase with the guidance of experienced team members In the first 3 months: * Ship independently on impactful product features and improvements * Participate in architecture discussions around scaling workflows, data models, and integrations * Work alongside other engineers to implement robust, reliable data flows * Develop a deep understanding of how companies manage and automate equity * Participate in code reviews and help maintain our engineering standards In the first 6–12 months: * Take ownership of key features and improvements within your team’s domain * Help shape the technical direction and architecture of Ledgy’s equity platform * Collaborate with Product and Design to deliver polished, user-centric experiences * Mentor other engineers and share expertise in automation, data modeling, and scalability Teams we’re hiring for Core Equity — Owns the foundational logic that powers Ledgy’s equity engine. Every equity-related event  such as issuing shares, creating new pools, or adjusting ownership — generates transactions. This team defines and maintains the transaction logic, data model, and core domain behaviour that ensure Ledgy’s platform remains accurate, scalable, and compliant. Workflows & Automation — Focuses on automating complex equity workflows and integrating with third-party services, including the trading exchange. The team builds systems that help company admins efficiently onboard and offboard employees, automate equity grants and terminations, and enable employees to sell their shares seamlessly once vested. Reporting — Transforms Ledgy’s core equity data into financial, operational, and compliance reports. The team manages large, complex datasets and ensures reporting is accurate, performant, and reliable across jurisdictions and company structures. Their work powers the insights companies and auditors rely on for decision-making and transparency. The job is a good fit if: * You have 7+ years of experience working as a Software Engineer * You're excited about the impact of equity on entrepreneurship and its real-world impact for companies * You enjoy tackling complex financial data transformations and compliance requirements * You enjoy writing clean, maintainable TypeScript code, both in the backend and frontend * You are excited to work with React, NodeJS, and MongoDB * You thrive in collaborative environments and enjoy pair programming * You take pride in creating robust, tested solutions for critical business operations Being part of Ledgy means: * Recharge and re-energize with flexible working hours, 25 days of vacation, and up to 40 days of remote work from outside your home country. * We make space for your own professional development, with a generous yearly learning & development budget. * This role will receive a competitive salary + benefits + equity. All salaries are aligned with competitively benchmarked ranges based on work location and levelling. * For candidates based in London or Zurich we use a hybrid work model of 1 day in the office per week. Our tech stack: We have a modern, cohesive stack that lets us move fast while maintaining quality: * Language: TypeScript * Frontend: React, Tailwind CSS, tRPC * Backend: tRPC, Node.js, MongoDB * Infrastructure: GCP, Terraform Cloud, Kubernetes, Docker, Github Actions The interview process: * CV Review: we review your resume to see if we might be a good fit * Getting to know you (30 min): meet with someone from our people team to talk about your experience and to answer questions about the role * Live Coding (75 min): We'll present you with an equity domain problem to solve collaboratively using your preferred language and IDE * System Design (60 min): You'll walk us through an architecture you've significantly contributed to in the past, and we'll explore different aspects based on your experience * Culture Interview: A chance to meet one of our founders for a 30 minute chat about Ledgy’s mission and values * Offer 🎉

PhysicsX

ABOUT US PhysicsX is a deep-tech company with roots in numerical physics and Formula One, dedicated to accelerating hardware innovation at the speed of software. We are building an AI-driven simulation software stack for engineering and manufacturing across advanced industries. By enabling high-fidelity, multi-physics simulation through AI inference across the entire engineering lifecycle, PhysicsX unlocks new levels of optimization and automation in design, manufacturing, and operations — empowering engineers to push the boundaries of possibility. Our customers include leading innovators in Aerospace & Defense, Materials, Energy, Semiconductors, and Automotive. THE ROLE PhysicsX is a deep-tech company with roots in numerical physics and Formula One, dedicated to accelerating hardware innovation at the speed of software. We are building an AI-driven simulation software stack for engineering and manufacturing across advanced industries. By enabling high-fidelity, multi-physics simulation through AI inference across the entire engineering lifecycle, PhysicsX unlocks new levels of optimization and automation in design, manufacturing, and operations, empowering engineers to push the boundaries of possibility. Our customers include leading innovators in Aerospace, Materials, Energy, Semiconductors, and Automotive. THE ROLE PhysicsX is building a platform that enables Data Scientists and Simulation Engineers to build, train, and deploy Deep Physics Models. Our platform serves multiple tenants across highly regulated industries, making robust identity, access control, and operational visibility foundational to everything we do. We're looking for a Senior Software Engineer to join our Core Services team, the team building the foundational primitives that gives our customers superpowers they've never had before. For decades, engineers have been trapped using siloed, rigid tools from the 90s. We're changing that by enabling secure, permissioned collaboration at the frontier of AI. You'll design and build the enterprise grade systems that make this possible. From fine-grained permissions to instrumentation, you'll create the primitives that every product across PhysicsX adopts, ensuring every user, service, and agentic workflow is securely identified, correctly scoped, and fully observable. You'll own the infrastructure that keeps our platform trustworthy, transparent, and ready for the future of manufacturing and engineering. WHAT YOU WILL DO * Design and implement authentication and authorisation systems, including identity provider integrations, token management, session handling, and SSO flows. * Architect and build fine-grained role-based and attribute-based access control (RBAC/ABAC) models that scale across multi-tenant environments. * Own the platform's permissions layer end-to-end: from policy definition and enforcement through auditing and compliance reporting. * Build and maintain telemetry infrastructure distributed tracing, structured logging, metrics collection, and alerting, to provide deep observability across services and environments. * Define and enforce security standards across APIs and services, including schema governance, data segregation, and least-privilege access patterns. * Design and implement identity and access patterns for AI agents, including MCP authentication, agent impersonation flows, and system account models that allow agents to act securely on behalf of users in a regulated, multi-tenant environment. * Contribute to the design of multi-service architectures, ensuring authentication and authorisation concerns are cleanly integrated and consistently enforced across both human and agentic workflows. * Drive best practices in CI/CD, automated testing, observability, and infrastructure-as-code. Build and maintain deployment pipelines, including zero-downtime and multi-service deployments. * Author and review Technical Decision Records. Participate in technology reviews to evaluate and adopt new tools and approaches. * Mentor junior and mid-level engineers, facilitate technical discussions, and build consensus around architectural decisions. WHAT YOU BRING TO THE TABLE * A passion for the craft, you're driven by engineering excellence and committed to fostering that culture across the team. * Strong software engineering foundations, solid grasp of algorithms, data structures, and system design. You write clean, maintainable, testable code and have strong command of Golang and Python. * Authentication and identity expertise, hands-on experience building or integrating identity and access management systems (e.g., Keycloak, Auth0, Okta). Deep understanding of OAuth 2.0, OIDC, SAML, and token-based authentication flows. Ability to effectively leverage cloud provider IAM systems (e.g., AWS IAM, GCP IAM, Azure AD). * Authorisation and permissions design, proven experience implementing RBAC, ABAC, or policy-as-code frameworks (e.g., OPA/Rego, Cedar) in production multi-tenant systems. * Telemetry and observability, experience designing and operating metrics, tracing, and logging pipelines (e.g., OpenTelemetry, Prometheus, Grafana, Jaeger). You understand what it takes to make distributed systems genuinely observable. * Kubernetes and GitOps, strong working knowledge of Kubernetes and ArgoCD, including deploying, managing, and troubleshooting services in production clusters. * API and service design maturity, experience designing multi-service systems with attention to schema governance, forward compatibility, and secure data access patterns. Proven ability to develop schema drift mitigation strategies with minimal impact to dependent clients (e.g., forward-compatible schemas, ACLs, ambassador sidecars). * Agent governance awareness, understanding of how identity and permissions extend to agentic systems, including MCP auth, impersonation, system accounts, and scoped token delegation. * Security awareness, familiarity with threat modelling, secure coding practices, and participating in security testing and compliance workflows. * CI/CD and deployment expertise, hands-on experience building and optimising CI/CD pipelines, including multi-service and zero-downtime deployments across numerous customer environments. * Communication and collaboration, excellent communication skills to work across teams, understand requirements from research scientists and product stakeholders, and translate them into technical specifications. * AI-native mindset, you follow the frontier of agentic systems and AI tooling. You naturally think about how infrastructure needs to evolve when agents, not just humans, are the consumers of your APIs and services. You actively use AI coding tools (e.g., Copilot, Cursor, Claude Code) in your daily workflow and see them as a force multiplier, not a novelty. * Incremental mindset, you work in small steps toward larger goals, driving change through continuous improvement rather than massive redesigns. You can zoom in on details and zoom out to see the big picture. IDEALLY * Polyglot programming, deep expertise in Python and Golang, with exposure to other languages such as Rust or C++. * Advanced Kubernetes, ability to leverage resources that extend the Kubernetes API (e.g., CRDs, Operators) and infrastructure configuration tools (Crossplane, Helm charts). * Infrastructure flexibility, understanding of what it takes to build software that runs in cloud, on-premises, and air-gapped environments. * Advanced testing, experience with fuzzing, deterministic simulation testing, or fault injection in production systems. What we offer Build what actually matters Help shape an AI-native engineering company at a formative stage, tackling problems that genuinely matter for industry and society. This is work with real-world impact - and something you can be proud to stand behind. Learn alongside exceptional people Work with a high-caliber, collaborative team of engineers, scientists, and operators who care deeply about doing great work, and about helping each other get better. We come from diverse backgrounds, but we share a commitment to operating at the highest level and addressing some of the most complex challenges out there. If you’re ambitious, thoughtful, and driven by impact, you’ll feel at home. Influence over hierarchy We operate with a flat structure: good ideas win - wherever they come from. Questioning assumptions and challenging the status quo isn’t just welcomed, it’s expected. Sustainable pace, long-term ambition Building meaningful technology is a marathon, not a sprint. We believe in balancing focused, ambitious work with a life beyond it. Our hybrid model blends time together in our Shoreditch office with work-from-home days, giving you the flexibility to work sustainably while staying connected in person. And it doesn’t stop there … 🚀 Equity options - share meaningfully in the company you’re helping to build. 🏦 10% employer pension contribution - because investing in future matters. 🍽️ Free office lunches - to keep you energised and focused. 👶 Enhanced parental leave - 3 months full pay paternity and 6 months full pay maternity leave, to provide extra flexibility during the moments that matter most. 🍼 YellowNest nursery scheme - to help working parents manage childcare costs. ☀️ 25 days of Annual Leave (+ Public Holidays) - because taking time to rest matters. 🏥 Private medical insurance - 100% employee cover, giving you complete peace of mind. 💪 Wellhub Subscription - gain access to thousands of gyms, classes and wellness apps, supporting both physical and mental wellbeing. 👀 Eye tests - because good work depends on good health. 📈 Personal development - dedicated support for learning, development, and leveling up over time. 💛 Employee Assistance Programme (EAP) - confidential wellbeing support, available whenever you need it. 🚲 Bike2Work scheme and 🚆 Season ticket loan - to make getting to work easier and greener. 🚗 Octopus EV salary sacrifice - for a simpler, more sustainable way to drive electric. 🔎 Watch this space, we’re continuing to build this as we grow…   We value diversity and are committed to equal employment opportunity regardless of sex, race, religion, ethnicity, nationality, disability, age, sexual orientation or gender identity. We strongly encourage individuals from groups traditionally underrepresented in tech to apply. To help make a change, we sponsor bright women from disadvantaged backgrounds through their university degrees in science and mathematics.    We collect diversity and inclusion data solely for the purpose of monitoring the effectiveness of our equal opportunities policies and ensuring compliance with UK employment and equality legislation. This information is confidential, used only in aggregate form, and will not influence the outcome of your application.