Senior Full Stack Software Developer (Post-Trade)

Ophelos

OUR MISSION At Ophelos, we believe in a different way to deal with debt. One that puts empathy and understanding front and centre, approaching our customers as individuals — no matter what they’re going through. For too long, people in debt have borne the brunt of poor industry practices. Intimidating tactics, time-consuming customer service and a one-size-fits-all approach that overlooks the reasons anyone can fall into debt in the first place. Meanwhile, businesses suffer too. Poor customer experience translates to poor customer satisfaction, high churn rates, bad brand reputation and ultimately missed opportunities. That’s why we’re taking a radically different approach. Pioneering an industry-first AI-native collections platform, we build products that help individuals clear their debts in a way that suits them, whilst providing businesses with an improved customer experience and game-changing insights into their customer base. Since our launch in 2021, we’ve worked with some of the UK’s leading companies, including Octopus, Scottish Power and Philips — helping millions of people move toward a more stable, debt-free future. In 2023, we were acquired by Intrum, Europe’s biggest credit management service and have begun the next phase in our growth — expansion into 17 European markets over the next two years. SENIOR PRODUCT ENGINEER (FULL STACK) We are seeking an enthusiastic and ambitious Senior Product Engineer with a keen eye for quality to join our growing Engineering function. You will be joining our Payments squad, responsible for building out our cross-market flexible Payments capability. This is a team which has recently transitioned to being "LLM-first" in their working style, so you would be joining at a critical moment to shape our ways of working and our approaches to LLM-based tooling. At Ophelos, we don't have traditional product or design functions — our engineers own the full problem, from identifying what needs to be built through to shipping and iterating on it. If you're energised by that kind of end-to-end ownership and want to operate closer to the product than most engineering roles allow, this is the role for you. In this role, you'll get to: * Design, implement and deliver software features with full ownership from start to finish — from problem definition through to production. * Take genuine product ownership: identify user and business needs, define solutions, and make pragmatic trade-offs — not just execute on a brief handed to you. * Have real opinions about how things should be built, and back them up. We want engineers who push back — on a design pattern, a tool choice, or a suggestion from an AI agent — when the second- and third-order consequences don't stack up. * Work in an environment that's largely backend-heavy right now (though that mix will evolve), with the autonomy to shape how it's built. * Collaborate as part of a close & multi-disciplinary team. Your work will have meaningful and measurable impact on our organisation and products. * Own business-critical components and ensure their stability and maintainability — and know how to prove it, through the numbers you track. * Mentor other members of the team to ensure technical excellence and continuously raise the bar when it comes to engineering standards. * Share your ideas with the team and build products that make an incredibly impactful difference to society and people's lives. Ophelos is an AI-first technical organisation and effective use of LLMs is central to how our engineers work. Claude Code and other agentic tools are critical to our toolbox, and we're as interested in engineers who bring their own AI-assisted workflows and habits to the team as we are in engineers who already use ours. The right person for this role is excited by this world, uses it daily in their own work — professionally or personally — and enjoys helping others get better at it too. Stack-wise, we run TypeScript, Python, and Ruby at various levels. For this role we're really seeking a polyglot Software Engineer for whom specific implementation language is not critical. More broadly, our stack includes: * A modern web application framework (we use FastAPI; comparable experience elsewhere is fine) * A relational database layer (we use PostgreSQL) * Workflow orchestration and data infrastructure tooling * AWS and container-based cloud infrastructure * Claude Code for LLM-first software engineering * Datadog for monitoring & observability Ophelos operates hybrid working, and believes face-to-face working time is essential for planning and alignment. Our teams spend three days each week working in-person from our comfortable office near Liverpool Street in London. ABOUT YOU More than anything we are interested in your general experience as a software developer and your approach to solving problems. The ideal candidate thinks like a product owner and builds like an engineer — someone who is energised by ambiguity, comfortable shaping the problem as much as solving it, and who takes personal pride in the real-world impact of what they ship. Some experience in the following is important for this role: * At least 5 years of experience in full stack engineering, with real depth somewhere in your backend work - this role skews backend-heavy today. * Experience with TypeScript, Python, Ruby, or a similarly high-level language, and comfort designing and integrating APIs - particularly in environments where data sensitivity or regulation raises the stakes. * Breadth across problems and systems tends to serve people better here than narrow specialisation in one area - we'd rather hear about the range of things you've owned than the depth of one niche. * You enjoy learning new technologies and are passionate about experimenting to figure out how to build things in a better way. * You're comfortable working from a problem statement rather than a fully specced brief - you can move from ambiguity to a clear technical approach independently, and you actively contribute to shaping what gets built, not just how. * Genuine enthusiasm for using the latest LLM tools — Claude Code, Cursor, Codex or similar — is critical, as is the intent to keep developing your skills as the agentic software engineering landscape evolves. Bonus points if you've helped teammates or a wider team get better at this too. * You don't just ship - you measure. You can point to how you know something you built actually worked, whether that's a business number, a reliability metric, or both. * Attention to detail, intellectual curiosity & a willingness to embrace the changing technical landscape we find ourselves in. * You are excited about Ophelos' mission to support households and businesses to break the vicious debt cycle. Experience in fintech, or in regulated or compliance-heavy environments more broadly, is a genuine bonus - but we've hired brilliant people here without it, so don't rule yourself out if that's not your background. ABOUT OUR TEAM Ophelos launched in June of 2021, backed by investors such as AlbionVC, Connect Ventures and Fly Ventures. In 2023, we were acquired by Intrum, Europe’s biggest credit management service. Our growing team has team helped build some of the world’s most successful businesses, including the likes of Monzo, Google, Oracle, ASAPP, IBM and more — in addition to pioneering innovative products, sitting at the intersection of enterprise, financial technology, artificial intelligence and academia, working with institutions such as Oxford University, the University of Amsterdam and the University of Hong Kong. OUR VALUES Supporting customers and businesses to improve their financial health is a long-term mission. Our company values act as our north star, steering our every move as an organisation and are the backbone of our unique company culture. Our values and culture allow us to stay true to our larger purpose, even as we continue to grow at a rapid pace. Customers and Clients first – We exist to help real people move through debt and to get clients paid back. This commitment drives how we design products, deliver services, and interact with customers and clients daily. Dream big – We have ambition and drive to succeed - we’re not just raising the bar, we’re confidently asserting ourselves as the benchmark. Get it done – We’re decisive and embrace a sense of urgency; we don’t let opportunities get away from us. We’d rather act quickly and take informed risks, iterating and learning as we go.  Win as one - We work as one team, supporting each other and aiming for shared goals. At Ophelos, the team isn’t just individual departments - it’s all of us together.  We challenge and support each other because we care about everyone’s growth and success.  Ophelos is committed to creating a diverse work environment and is proud to be an equal opportunity workplace, providing equal employment and advancement opportunities to all team members. We are building an environment where every Ophelos team member can thrive, feel a sense of belonging, and do the best work of their careers. We value diversity and recruit, hire, and promote individuals solely based on talent, qualifications, competence, and merit. We evaluate candidates without regard to race, colour, religion, age, sex, sexual orientation, gender identity, national origin, disability, or other protected characteristics as required by law and as a matter of our company values. GDPR NOTICE  When you apply to a job on this site, the personal data contained in your application will be collected by Ophelos ("Controller"), located at 1 Finsbury Ave, London EC2M 2PF, and can be contacted by emailing support@ophelos.com. Controller's data protection contact is Kofi Barnes, who can be contacted at support@ophelos.com. This notice explains how we process your personal data throughout our recruitment process, including at the interview stage described below. Applying for a role with Ophelos is subject to the practices described in this notice — it is not a separate agreement you sign, but a description of how the recruitment process works. You won't be given a separate notice at each stage; Ophelos retains discretion over which of the described tools and processes are applied to any given application or interview, within the purposes set out below. This discretion does not extend to introducing automated decision-making without human review — that is addressed separately below. What we use your data for Your personal data will be processed for the purposes of managing Controller's recruitment-related activities, which include reviewing applications, setting up and conducting interviews and tests, evaluating and assessing the results, and as is otherwise needed in the recruitment and hiring process. As part of this process, we use software tools — including AI-assisted tools — to help us organise, screen, and evaluate applications and interviews. This includes: * Automated analysis of CVs and application materials to identify relevant skills and experience * Automated analysis of interview transcripts to help summarise and score responses (see "Interviews" below) * Generating scores, summaries, or insights to assist our recruiters Currently, these AI-assisted outputs are advisory only. A human recruiter reviews every application and every AI-generated score or summary before any decision is made, and no application is filtered out or rejected by an automated process alone. We may in future use automated tools to make, or take part in making, decisions about your application without human review at that stage, if we do so in a way that complies with applicable law at the time — for example, by obtaining your explicit consent, or where the decision is necessary for entering into a contract with you, and in either case only with appropriate safeguards, including your ability to request human review of, and to contest, that decision. If we intend to introduce this, we will update this notice and separately inform you before it applies to your application — this notice alone does not authorise it. We also use historical, aggregated recruitment data to improve our processes generally — for example, to better understand which factors tend to be associated with successful hires. Where this involves data from past applicants, it is anonymised or aggregated before use, and is not used to make any decision about a specific individual. Such processing is legally permissible under Art. 6(1)(f) UK/EU GDPR as necessary for the legitimate interests pursued by the Controller: the solicitation, evaluation, and selection of applicants for employment, and the improvement of Controller's recruitment processes. Interviews — recording and transcription If you're invited to an interview conducted by video or phone call, it will be recorded and automatically transcribed as a standard part of our recruitment process — this is described in this notice, which applies to your application as explained above. Where an interview is recorded: * The interview will be recorded and transcribed using our video-calling provider (Google Meet). * The transcript will be processed by AI tools (including models provided by Anthropic and Google) to help generate a summary and structured notes for the interview panel, and to help train and improve our own recruitment tools as described above. * The recording, transcript, and any AI-generated summary will be stored on Ophelos's systems (hosted via Cloudflare) and in Greenhouse. * A human interviewer/panel always reviews the AI-generated summary as part of forming their own assessment — it is a starting point for the panel, not a decision in itself. Recording and transcribing interviews in this way is necessary for us to evaluate all candidates fairly and consistently, and is carried out under our legitimate interests (Art. 6(1)(f) GDPR) in running a fair, well-documented recruitment process. Who we share your data with Your personal data will be shared with the following processors, engaged by Controller to help manage its recruitment and hiring process: * Greenhouse Software, Inc. — applicant tracking system (United States) * Google LLC — video interview hosting/recording (Google Meet), and AI models used to help analyse application and interview materials (United States) * Anthropic, PBC — AI models used to help analyse and summarise application and interview materials (United States) * Cloudflare, Inc. — infrastructure and data storage supporting our recruitment tools [confirm storage region before publishing] We use application and interview data, including through AI-assisted tools, to train and improve our own internal recruitment tools and models — for example, to refine how we identify relevant skills and experience, and to better understand what tends to be associated with successful hires. This is part of how we evaluate and improve our recruitment process on an ongoing basis. The third-party AI providers who process this data on our behalf do not use it to train their own general-purpose AI models — it is used only to generate the specific outputs described in this notice. International data transfers Because the above providers are located in or transfer data to the United States, if you are located outside the United States, your personal data will be transferred to the United States once you submit it or once your interview is processed. Where the European Commission has not made an adequacy determination covering such a transfer, it is subject to appropriate safeguards, including Standard Contractual Clauses and/or the EU-U.S. Data Privacy Framework where the recipient is certified. You can obtain a copy of the relevant safeguards by contacting support@ophelos.com. How long we keep your data Your personal data, including any interview recordings, transcripts, and AI-generated summaries, will be retained for the duration of the recruitment process and for 24 months afterwards, to allow us to consider you for other roles and manage any related legal claims, after which it will be deleted or anonymised. You can request earlier deletion at any time by contacting support@ophelos.com. Your rights Under the GDPR, you have the right to request access to your personal data, to request that it be rectified or erased, and to request that processing be restricted. You also have the right to data portability and the right to object to processing based on legitimate interests, including interview recording — though for the reasons explained above, we may not be able to progress an application where a candidate objects to standard recording of the interview stage. In addition, you may lodge a complaint with an EU or UK supervisory authority (in the UK, the Information Commissioner's Office).

Ably

Our everyday digital experiences are in the midst of a realtime revolution. Whether chatting alongside a livestreaming event, receiving realtime financial information, or working with colleagues in an online collaborative environment - consumers simply expect realtime digital experiences as standard. At Ably we’re not just witnessing this revolution, we’re powering it - at scale. At the heart of our mission lies a commitment to putting developers first. Ably provides a suite of products to build, extend, and deliver powerful digital experiences in realtime, delivering billions of messages for millions of devices every day and supporting organizations like Harness, EA, Panasonic and HubSpot. Working at Ably means helping to build the infrastructure and technology that will power and shape the future of the internet. The opportunity in front of us is immense. And we’d like your help. ABOUT THIS ROLE As the Technical Lead for Developer Experience at Ably you will report directly to our CTO and co-own the DevEx vision and strategy, transforming our dashboard, documentation platform, and control plane into a world-class experience. You are a senior, hands-on engineer who’s passionate about building for developers like yourself; someone who’ll obsess over the developer journey and elevate the user experience of the Ably platform. You’ll blend deep full-stack expertise with a strong product mindset and lead a team of five engineers where the feedback loop is immediate, because you and your team are the target users of the very ecosystem you are building. DAY TO DAY YOU WILL * Obsess over developer experience. You’ll have broad responsibility for elevating how developers interact with Ably’s platform and services, partnering with the DevEx PM as a unified leadership team to deliver a developer experience that becomes a reference point for the industry. * Lead technical execution and vision. You’ll lead a team of five engineers building customer-facing web applications and own the technical architecture and design decisions for our dashboard, docs platform, marketing website, and billing UI. * Drive a product-first engineering culture. You’ll foster an environment where engineers are themselves principal stakeholders of product features, and obsess over customer outcomes. You’ll challenge the "feature factory" mentality and build a team that takes true ownership of the product. * Thrive in a rapid iteration environment. You’ll operate in a high-velocity workspace where PMs, customers, and engineers co-create features. You’ll lead the team in working full-stack to iterate, improve, and ship improvements quickly. * Champion AI-assisted development. You’ll be a catalyst for AI adoption across the team. You’ll leverage LLMs and AI tools to accelerate velocity without compromising on engineering integrity. * Guide engineering outcomes and quality. You’ll set and enforce high standards for code review, testing, and production readiness. You will participate in incident response and coordinate with the Infrastructure team on platform dependencies and deployments. * Mentor and grow the team. You’ll manage performance, career development, and hiring. You will hold the team accountable for delivery commitments while providing the mentorship needed to turn engineers into product-minded leaders. WE'D LOVE TO TALK IF YOU HAVE * A natural empathy for developer customers because you are the target audience. You are genuinely excited about building developer tools and instinctively understand what good looks like. You're fluent in API design, documentation, and the nuances that differentiate a great developer journey. * Extensive experience leading teams at B2B SaaS or API-first companies. You have a track record of building product-minded engineering cultures where teams take initiative and ownership of product outcomes. * A strong software engineering background with expertise in React, TypeScript, and modern JavaScript, alongside backend experience in Ruby on Rails or Node.js. You're comfortable writing code and building prototypes using our APIs, and have built and shipped customer-facing web applications at scale. * An AI-first mindset. You champion the use of  LLMs and AI tools as productivity multipliers for the team. You see AI as an enabler for higher velocity and output, not a replacement for engineering judgment. * Experience at a startup or growth-stage company or adaptability to thrive in a fast-paced, agile environment with a focus on rapid iteration. To be effective in this role you’ll need excellent communication and cross-functional collaboration skills. BONUS POINTS IF YOU HAVE * Experience delivering solutions used by software developers (developer tooling or APIs) or similar technical personas. * An understanding of pub/sub and familiarity with distributed systems and event based architectures. WHAT’S IT LIKE TO WORK AT ABLY? We’re tackling planet-scale problems and our ambitions are a testament to that. You’ll join a successful, deeply motivated and collaborative team that thrives on innovation, experimentation and autonomy. To get a sense of life at Ably, visit our careers page. You can also read about the origins of Ably's core values on our blog. We believe in fostering a culture that's built on inclusivity and mutual respect among all team members, and we recognise that each individual is different and will want to be supported in their role in different ways. We provide a range of perks and benefits to aid folks' development and wellbeing, allowing them to be their best selves and do great work. * A remote-first and flexible work environment. UK-based teams come together in person once per month in our London hub (next to Old Street) and we get together as a company twice per year. Aside from that, you’re welcome to work wherever suits best for you. * Equity. We’re a growing start-up and we want all team to members to share in the success of the company through our EMI share options programme. * Enhanced holiday allowance. Our policy provides Ablyans with 28 days of paid annual leave (27 regular days, plus a day off to enjoy your birthday). * Enhanced parental leave package, so that you can take the time you need to get to know your new family member, rest and recover. * Home workstation budget of £500 on joining (and £150 p/a thereafter), so that your home office is set up to serve you well and that you have everything you need to work comfortably. * Personal learning and development budget of £1000 annually, and 5% L&D time during working hours to focus on improving your skillset. * Private healthcare with BUPA. * Medical cash plan to cover a range medical and dental costs. * Mental wellbeing coaching and counselling from Self Space. * Monthly wellbeing budget via Juno. * Life assurance and income protection. * Access to Tech & Cycle to Work schemes. * Weekly snack allowance for our end-of-week “Need To Know” meeting. * A fully-paid one-month sabbatical after five years with Ably. DIVERSITY, INCLUSION & BELONGING AT ABLY We believe our differences as individuals is what makes us great. Our people are at the heart of what we do, and we encourage everyone to be their most authentic self at Ably: we see inclusivity and openness as fundamental to creating long-term success as an organization. We encourage applications from all backgrounds regardless of age, disability, gender, sexual orientation, parental status, race, religion, educational background or neurodiversity. Ably has an amazing opportunity ahead of us, and we want anyone to be able to contribute to that opportunity. If you enjoy working as part of a technology company, value open source, and love solving hard problems - then we’d love to hear from you, regardless of whether you fit the job description exactly or not. If in doubt, drop us an email; we’d be more than happy to give you some advice on your application.

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 We are recruiting for a Senior Software Security Developer within our Core Platform Services Team. You will be responsible primarily for writing secure code components that many teams will use across the business. There is a strong emphasis on authentication for this role. What you will do * Design and implement platform security features and guardrails. * Act as an SME for security for the Core Services development team. This includes mentoring, performing threat modeling, sand ecurity code reviews. * Help shape incident response procedures and vulnerability management workflows * Support the response team by validating and remediating product security vulnerabilities. * Contribute to secure coding standards and provide training/mentorship to developers What you bring to the table * 8+ years in a developer role focused with strong focus on designing and building security features * Extensive RBAC/ABAC knowledge and implementation experience * Experience with user, agent, and machine authentication workflows. * Hands-on experience with secure coding, OWASP Top 10, and threat modeling * Strong developer skills and extensive experience shipping code to production. * Experienced in CI/CD, IaC, Python and Go. * Track record of balancing pragmatism and security rigor in a fast-paced team * Thorough knowledge of authentication and authorization protocols (e.g., OAuth, OpenID Connect, SAML, LDAP, etc.). * Strong communication skills, comfortable working across development teams and managing multiple initiatives. Nice to Have Skills * Strong understanding of AI security fundamentals * Participation in bug bounty programs * Familiarity with the BSIMM framework * Experience in cloud security including identity and access management and cloud-native services. 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.