Principal Data Engineer (Data Practice Lead)

YLD is a software engineering and product design consultancy, founded in 2013 based in London, Lisbon and Porto. We work with engineering and product leaders who know what good looks like and are frustrated by the gap between strategy and execution. We embed senior engineers and designers inside client teams, working in their codebase, their tooling, their delivery rhythm. AI runs through how our teams work, and we help clients adopt it into their own workflows too. About the role: We're building out data as a first-class practice at YLD, and we need someone in London who can be the credible technical voice in front of clients and prospects, not just describing what we could do, but backing it with real delivery experience. This is a senior role, reporting to our Head of Engineering. You'll sit alongside our commercial and client services leadership in meetings where technical credibility matters, help shape and win new engagements, and stay close enough to client work to guide it and step in yourself when an engagement needs you. Alongside, we expect you to build our external reputation in data through events, writing, and the wider community. About you: You've been a strong data engineer or data lead for years, and you're comfortable in front of a client as well as in a pull request. You know what good data work looks like well enough to spot it, or its absence, in the first ten minutes of a client conversation. You've probably led a team before. Consultancy background is a strong plus, but not essential if you've got real client or stakeholder exposure elsewhere. Your day-to-day responsibilities will look like this: Hands-on delivery (core, from day one) • Doing hands-on data engineering work directly, pipelines, transformation layers, models, and the infrastructure around them, not just guiding others • Adapting to different client contexts: legacy warehouse migrations, greenfield lakehouses, transformation layers that need rescuing • Guiding the wider team and unblocking hard technical problems as your remit grows beyond your own delivery • Defining and evolving our internal standards for data work: testing, documentation, project structure, code review • Mentoring and growing data engineers across the company Client and commercial (core, from day one) • Joining client and prospect meetings as the technical authority on data, alongside our client services and commercial leads • Shaping proposals and pitches, translating client problems into a credible data approach and a defensible scope • Acting as the escalation point on live data engagements when technical judgement calls need weight behind them • Travelling to client sites for workshops, discovery sessions, and in-person relationship building, and representing YLD at external data events Practice, talent, and external profile (growth, over the first year) • Owning the growth of YLD's data practice: capability, reputation, and headcount over time • Contributing to attracting and hiring strong data engineers into YLD • Representing YLD at data events and in the wider community as your standing in the market builds • Supporting our sales team so that data becomes something we can proactively sell, not just respond to You'll have the following skills and experience: Leadership and commercial • Consulting or agency experience is a strong plus, but real client or stakeholder-facing exposure elsewhere is acceptable • A track record of technical leadership: leading a team or function • Comfortable presenting to senior client stakeholders and holding your own under commercial pressure • Cross-functional fluency: you translate engineering constraints into business terms and negotiate realistic commitments • Appetite to build a public presence in the da