Solutions Engineer

At Lago we're on a mission to make billing simpler more transparent and more adaptable for SaaS companies.

As the leading open-source billing platform we empower businesses to 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 reflecting strong confidence in our vision and growth.

Our platform has garnered over 9 000 stars on GitHub a testament to our active and growing developer community. Companies such as PayPal CoreWeave Synthesia and Mistral.ai choose Lago for their billing.

We're a team of ambitious focused individuals who work together to 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 adapt quickly. 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)

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Run technical discovery calls to understand prospects' pricing models billing infrastructure and integration requirements

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Lead and own product demos — building bespoke demo environments tailored to each prospect's use cases not off-the-shelf scripts

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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

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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

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Surface and work through product gaps creatively: propose API-level workarounds validate feasibility with engineering and frame limitations transparently without losing deals

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Produce competitive technical analysis and maintain battle cards as Lago's market position evolves

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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)

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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)

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Serve as the primary technical point of contact through the implementation phase owning the customer relationship until they go live

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Conduct proactive check-ins and syncs throughout implementation to unblock customers and prevent issues before they escalate

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Identify expansion and optimisation opportunities within existing accounts as usage matures

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Partner with Customer Success and Support to ensure a clean handoff after go-live

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Feed recurring implementation pain points back to Product and Engineering to inform roadmap prioritisation

Who you are

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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

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A natural deal-shaper — you understand commercial dynamics and help AEs close by removing technical blockers not by just answering questions

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Someone who writes thorough clear post-call debriefs without being asked: every prospect interaction generates signal for the team

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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

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Genuinely curious about how billing and pricing systems work — the nuances of metering aggregation invoice generation and revenue recognition interest you

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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

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You're not someone who reads from a slide deck and escalates anything technical to engineering

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You're not indifferent to whether a deal closes or a customer goes live — you feel ownership over both outcomes

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You're not a siloed individual contributor — you share context freely write things down and loop in the right people early

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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

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5+ years in a Solutions Engineering Sales Engineering or technical pre-sales role — ideally in a developer tools API-first or infrastructure SaaS company

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Strong technical foundation: comfortable with REST APIs JSON SQL and working through integration architectures

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Demonstrated experience running complex evaluations and POCs with enterprise or mid-market prospects

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Excellent written and verbal communication skills; fluent in English (French is a significant plus for European accounts)

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Track record of collaborating closely with AEs and founders in a fast-moving sales environment

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Ability to manage multiple active deals and customer implementations simultaneously without dropping the ball

Nice to have

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Experience with billing usage-based pricing fintech or revenue infrastructure

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Familiarity with scripting (Python bash JS) for demo environment setup or automation

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Background in post-sales implementation or customer success engineering

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Exposure to open-source products or developer communities

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Experience presenting to both engineering and finance/executive audiences

How we work

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Written async-friendly culture

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Direct access to Product and Engineering teams

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Transparent user-driven roadmap

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Autonomy and ownership from Day 1

Why Join Lago?

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Work with top-tier talent : Join a team that values excellence ambition and accountability

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Shape the future of fintech : Be part of a fast-growing company building the best open-source billing platform

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Remote-first in Europe : Work from anywhere in Europe

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Competitive package : Competitive salary and stock options

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Make an impact : Your work will directly influence deals and customers at companies like PayPal CoreWeave Synthesia and Mistral.ai

Ready to Build with Us?

If you're excited about joining a high-talent team to solve meaningful problems and help businesses thrive we'd love to hear from you. Apply today and let's build something remarkable—together.

Location type: Remote

Primary Location: Remote Europe

Team: GTM

Work Type: Full Time/Permanent Contract

Salary: 60 000–90 000 EUR per year

(Applicants must be based in Europe. Applications from other locations will not be considered.)