ABOUT LAGO At Lago, we're on a mission to make Monetization simpler for tech companies. As the leading open-source billing platform, we help businesses build flexible pricing models and scale with confidence. We've raised over $22 million in funding from top-tier investors including Y Combinator and FirstMark. Our platform has garnered around 10K stars on GitHub, a testament to our active and growing developer community. Companies such as PayPal, CoreWeave, Synthesia, and Mistral.ai http://Mistral.ai choose Lago for their billing. And we have barely spent any money on Marketing or Ads so far. We're a team of ambitious, focused individuals who solve hard problems with excellence and accountability. At Lago, we value reliability and proactivity. We trust each other to own tasks, drive them to completion, and continuously improve them. While we encourage you to try fast and “fail fast”, we also expect you to learn fast: make mistakes, but don't make the same one twice. If you're excited by challenges and want to grow alongside a high-performing, supportive team, this is the place for you. OVERVIEW We're hiring a Solutions Engineer in Europe to be the technical backbone of our GTM motion — from first demo to successful go-live and beyond. This is a dual-focus role: pre-sales first, where you help prospects evaluate and understand Lago deeply, and post-sales second, where you ensure the customers who sign with us get to production and see value. You will work directly with our AE team, co-founders, and product to shape deals and guide implementations. This isn't a classic SE role where you polish the same demo script for every prospect. Every billing architecture is different, every contract is custom, and every customer has gaps you'll need to bridge creatively. You'll need to go deep — technically and commercially — to help prospects understand what's possible in Lago and translate that into real, working configurations. You'll be joining a small, high-ownership team and working alongside people who already set the standard for what great looks like in this function at Lago. WHAT YOU'LL BE DOING Pre-sales (primary focus) - Run technical discovery calls to understand prospects' pricing models, billing infrastructure, and integration requirements - Lead and own product demos — building bespoke demo environments tailored to each prospect's use cases, not off-the-shelf scripts - Manage technical evaluations and cloud trials end-to-end: configure demo data, set up trial environments, run technical workshops, and stay close to the prospect throughout - Write clear, honest deal debriefs that capture what landed, what's at risk, and what actions are needed — shared with the AE and founder team - Surface and work through product gaps creatively: propose API-level workarounds, validate feasibility with engineering, and frame limitations transparently without losing deals - Produce competitive technical analysis and maintain battle cards as Lago's market position evolves - Partner with AEs on commercial strategy: know when to push for a close, when to escalate to a founder, and how to sequence the conversation Post-sales (secondary focus) - Lead onboarding for new customers — both their engineering teams (API integration, event schema, webhooks) and their finance and ops teams (plan configuration, invoice flows, reporting) - Serve as the primary technical point of contact through the implementation phase, owning the customer relationship until they go live - Conduct proactive check-ins and syncs throughout implementation to unblock customers and prevent issues before they escalate - Identify expansion and optimisation opportunities within existing accounts as usage matures - Partner with Customer Success and Support to ensure a clean handoff after go-live - Feed recurring implementation pain points back to Product and Engineering to inform roadmap prioritisation WHO YOU ARE - A strong technical generalist who can read API documentation, write a curl command, debug a webhook, and explain the result to a VP of Finance in the same afternoon - A natural deal-shaper — you understand commercial dynamics and help AEs close by removing technical blockers, not by just answering questions - Someone who writes thorough, clear post-call debriefs without being asked: every prospect interaction generates signal for the team - Comfortable with ambiguity: you don't have a perfect answer for every gap, but you're good at finding one that keeps the deal alive and serves the customer well - Genuinely curious about how billing and pricing systems work — the nuances of metering, aggregation, invoice generation, and revenue recognition interest you - Proactive about internal tooling and process: if you can script or automate something that saves the team time, you do it WHO YOU'RE NOT - You're not someone who reads from a slide deck and escalates anything technical to engineering - You're not indifferent to whether a deal closes or a customer goes live — you feel ownership over both outcomes - You're not a siloed individual contributor — you share context freely, write things down, and loop in the right people early - You're not passive in post-sales: a customer who's stuck is a customer who churns, and you move quickly to prevent that REQUIREMENTS - 5+ years in a Solutions Engineering, Sales Engineering, or technical pre-sales role — ideally in a developer tools, API-first, or infrastructure SaaS company - Strong technical foundation: comfortable with REST APIs, JSON, SQL, and working through integration architectures - Demonstrated experience running complex evaluations and POCs with enterprise or mid-market prospects - Excellent written and verbal communication skills; fluent in English (French is a significant plus for European accounts) - Track record of collaborating closely with AEs and founders in a fast-moving sales environment - Ab