Polyglot Engineer (JS/Python/Go)

YLD

Location: Portugal Department: Engineering Employment Type: Permanent ABOUT YLD: Our goal is to help our clients keep moving forward. We work with them to build the skills and capabilities they need to stay ahead of the competition, and we know our success only happens when they succeed. We’re a team of curious, talented people, and we’re committed to making YLD a place where great people want to work, grow, and stay. We’re a remote-first consultancy specialising in software engineering, product design, and data. Our teams are based across London, Lisbon, and Porto, and we create digital solutions that continue to deliver value long after our work is done. ABOUT THE ROLE: As a Senior Software Engineer at YLD, you’ll be part of a client team building innovative products. We’re looking for someone curious, passionate, driven, and enthusiastic. You should be skilled in problem-solving and experienced in designing scalable, resilient, and fault-tolerant architectures. You’re also an effective communicator and a strong team player. Together with your team, you’ll thrive in a fast-paced engineering environment, delivering outstanding results and exciting projects. YOUR DAY-TO-DAY RESPONSIBILITIES WILL LOOK LIKE THIS: * Crafting excellent products! You will be building new features that meet the needs of our clients and customers; * Continuously delivering changes to products, as our client is moving to a full CI/CD model; * Working closely with your team, regularly collaborating and on engineering initiatives, to continually push yourselves to be better; * Learning, growing, and mentoring the engineering team to accelerate their career growth and encourage them to progress; * Working with the Lead to architect, design, build, and deliver highly available, always-on, zero downtime products; * Being responsible for the production operation and monitoring of products in line with SLAs; * Driving good practices within your team, making an impact on the whole department; * Participating in regular show and tells, promoting your work to both your department and the wider company. PREFERRED SKILLS * Proficiency in JavaScript/TypeScript, Python, and/or Go, with the ability to rapidly learn new languages; * Experience with modern frameworks across the stack (FastAPI, Gin, Express, etc.); * Production experience with React, modern build tools, state management, responsive design, and accessibility standards; * Comprehensive testing experience (unit, integration, E2E, security) and performance optimization; * Scalable system design patterns, load balancing, and high-availability architectures; * Database design and optimization (both relational and NoSQL); * API development (REST, GraphQL, gRPC) and event-driven architectures; * Caching strategies and message queue systems (Redis, Kafka, RabbitMQ); * Cloud platforms (AWS, Azure, GCP) with containerisation (Docker, Kubernetes); * CI/CD pipelines and Infrastructure as Code (Terraform, CloudFormation); * Monitoring, observability, and performance optimisation tools; * You can keep a cool head when debugging production issues; * Use AI tools to augment your work, applying sound judgement to adopt emerging technologies where they genuinely add value and increase your impact as an engineer. YOU SHOULD APPLY IF YOU ARE: * Self-motivated, proactive and always looking for ways to improve and develop yourself; * A good communicator, both in writing and verbally. You’ll be able to explain technical ideas and concepts in business-friendly language. * Detail-oriented; * Possess strong problem-solving skills that balance innovation with pragmatic technology choices to solve business needs; * Used to working in a team-oriented, collaborative environment; * Analytical and problem-solving-oriented; * A genuine believer in diversity and fairness. Benefits you’ll receive: * Company Private Health care * Enhanced fully paid maternity and paternity leave for up to 6 months * 25 days annual holiday (excluding Public Holidays) * €2000 annual allowance for Training/Conferences * €300 annual allowance for additional hardware * Mental Health support: access to Oli app * Meditation/Sleep support: Headspace or Calm app subscription * Bonus (depending on Company performance and results) * Company laptop * Generous referral schemes Our typical Recruitment Process looks like this: * 1st Interview with someone from the Talent team (30/45 mins) * Technical Interview with our Senior Developers (1h30) Get a glimpse of what it's like working at YLD! 🤳 Check out our LinkedIn page We live and breathe our values, and know you will too: * Growing every day * Including everyone * Relationships built on honesty and ethics * Inspiring solutions * Winning together We’re an equal-opportunity employer and value diversity in all its forms. We do not discriminate based on race, religion, colour, national origin, gender, sexual orientation, pregnancy or maternity, age, marital status, or disability. We also offer a remote-first working environment, with flexible working and work–life balance as standard for all employees.

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.

Deliveroo

STAFF SOFTWARE ENGINEER Join us in our mission to transform the way people shop and eat, where impact, innovation and growth drive everything we do. Our Engineering teams tackle complex technical challenges across a global, three-sided marketplace, building and scaling systems that serve millions of customers, riders and partners every day. From real-time logistics to resilient infrastructure and marketplace optimisation, we design, build and operate technology that powers Deliveroo’s growth at scale. We’re looking for a Staff Software Engineer to join our London, UK - Hybrid (3 days from the office) team. In this role, you’ll help us define technical solutions for critical business problems and lead the technical direction for complex, high-scale systems. Get to know our Engineering team — what drives us, how we work, and what you can expect. WHAT YOU’LL BE DOING You’ll be joining a high-impact engineering group focused on solving unstructured and ambiguous challenges. You will act as a technical authority, aligning non-adjacent teams to deliver results that move the needle for the entire organisation. Here’s what your day-to-day might look like: * Drive Technical Excellence: Act as a subject matter expert, providing high-level reviews and technical advice across multiple teams. * Architect Scalable Solutions: Define and design technical solutions for complex business problems within a high-traffic environment (20krpm+). * Lead Strategic Direction: Influence the long-term technical roadmap and manage project timelines, risks, and sustainable delivery paces. * Mentor & Coach: Support the growth of engineers across all levels and partner with up-and-coming leaders to scale our engineering culture. * Shape the Team: Lead engineering interviews and contribute to recruiting strategy to ensure we maintain a high bar for talent. WHAT YOU’LL NEED TO THRIVE Our ideal candidate will bring strong expertise in some of these areas and curiosity to grow in others: * Deep Technical Mastery: Significant experience building web-based applications at scale and a pride in writing readable, well-tested software. * Polyglot Mindset: Proficiency in (or a strong desire to learn) languages such as Go, Ruby, Python, Scala, or Rust. * Distributed Systems Expertise: Practical experience with relational databases (PostgreSQL) and NoSQL backends (Redis, DynamoDB, or Elasticsearch). * High-Scale Architecture: Proven ability to design and operate systems handling massive request volumes and complex logistical workflows. * Strategic Leadership: Strong understanding of how to align multiple disciplines and teams to resolve ambiguous technical challenges. WHY JOIN US? At Deliveroo, you’ll do work that matters—solving real-world problems in a three-sided marketplace that’s constantly evolving. We’re food lovers, problem solvers, community organisers, proud parents, and more, brought together by a shared drive to make things better. Working here you can expect to: 🔧 Solve meaningful problems at real scale Work on a complex, always-on marketplace that impacts millions every day. 🌱 See your impact, fast Ship, test and improve ideas quickly in a low-hierarchy, high-ownership environment. 🧠 Grow through challenge and ownership Take on big, ambiguous problems and accelerate your career with strong support. 🌎 A culture built for builders High standards, collaboration, flexible working and continuous learning. 💰 Share in the success you help create Competitive salary and equity options, so you’re rewarded for the impact you make. ➡️ Want a deeper look at how we build? Check out our Tech Blog. We aim to create a fair process that lets your skills shine—our interview typically includes 3-4 stages. Explore our Engineering Interview Guide here to help you feel confident at each stage. OUR GLOBAL STRUCTURE Deliveroo is now part of DoorDash, bringing together teams with even greater reach, scale, and ambition. Depending on your role, you may collaborate with teammates, systems, and leaders across DoorDash and Wolt. Together, we’re unlocking new possibilities as one global team. DIVERSITY, EQUITY AND INCLUSION At Deliveroo, we know that a great workplace reflects the world around us and that true diversity and inclusion make us stronger, more creative, and better at what we do. We’re committed to fostering an environment where everyone can do their best work and feel they belong. We believe in equality of opportunity and welcome candidates from all backgrounds regardless of age, gender, ethnicity, disability, sexual orientation, gender identity, socio-economic background, religion, or belief. If you have a disability or long-term health condition and need support to apply for one of our roles, or if you require any reasonable adjustments during the recruitment process, please contact our recruitment team at accommodations@deliveroo.co.uk and we’ll be happy to help ensure you have a fair and equitable experience. If you’re excited about solving meaningful problems at scale and growing with a supportive team, we’d love to hear from you.