---
title: 'Backend Product Engineer at Invopop'
canonical: 'https://feeny.ai/job/backend-product-engineer-invopop-madrid-dvhsq8be0pna'
type: 'job'
last_seen: '2026-09-09'
---

# Backend Product Engineer at Invopop

- **Company:** Invopop
- **Location:** Madrid, Spain
- **Compensation:** €50k–€90k
- **Employment:** full-time
- **Work type:** hybrid
- **Posted:** 2026-02-11
- **Last confirmed live:** 2026-09-09
- **Apply:** https://jobs.ashbyhq.com/invopop/8474e0f3-a851-44aa-adea-a8aab68086a6

## Job description

## TL;DR

- We’re a global e-invoicing platform operating in 25+ countries.
- Revenue grew 10x last year, and we plan to 3x in 2026.
- Role: own integrations end-to-end — research, define, build, ship, and iterate with customers.
- Looking for: 1–10 years of backend experience, builder mentality, fluent English, comfort with ambiguity, and complex domains.
- Compensation: €50k–€90k base + Stock Options.
- Location: Madrid (at least 3 days/week in our beautiful office in El Viso, Madrid).

⸻

Hi there 👋🏼,

I’m Juan, the CEO of Invopop. We help companies like Fever, DeepL, Booksy, and SumUp issue and receive invoices that comply with local requirements across 25+ countries.

We're looking for a Backend Product Engineer to join our team in Madrid. If you enjoy solving challenging problems with elegant software solutions, owning your roadmap, and directly interacting with customers, this role could be a great fit!

## ABOUT INVOPOP

Invopop helps global companies like SumUp, Fever, and DeepL issue and receive invoices across more than 25 countries through a single API.

In the next five years, more than 40 countries, including the entire EU, will mandate that businesses send invoices electronically in XML format and report them in real time to tax authorities. This reduces fraud and enables companies to automate invoice processing instead of relying on OCR. There’s only one catch: each country has defined unique standards, forcing global companies to build dozens of local integrations—or integrate once with Invopop. :)

Invopop was founded by Sam Lown, co-founder and former CTO of Cabify, and Juan Moliner (ex-BCG), based on Sam’s experience dealing with this problem at Cabify

We’ve raised €2.8M from top-tier venture capital firms, including YCombinator (W23), and have been named the Best Startup at South Summit 2024 and Madrid's Hottest Startup of 2024 by Wired.

## YOUR MISSION AS A BACKEND PRODUCT ENGINEER

With Invopop, users build workflows by chaining Actions, each action being managed by an App. An App is a standalone service focused on a single goal, such as reporting an invoice to a tax authority, synchronizing it with an external system (e.g., ERP), or transforming/enriching a document.

As a Staff Backend Product Engineer, you’ll be the owner of several Apps end-to-end, from the initial research to launching, and maintaining them in production:

- Investigate new countries and systems: read regulations and technical docs, turn ambiguity into clear requirements, and consult local experts when needed.
- Design and build integrations in Go on top of our modular architecture (NATS, CQRS patterns, Kubernetes on GCP).
- Make product decisions: what and how to build it, what to cut, and when to ship.
- Support customers using your Apps and iterate based on real feedback.
- Contribute to GOBL, our open-source standard for commercial documents.

## WHO WE’RE LOOKING FOR

- Backend engineering experience, ideally with Golang.
- Strong communication skills in English.
- Empathy for customers—you're eager to engage with clients and influence product decisions.
- Comfortable defining the scope as you build, learning new technologies, and navigating unfamiliar domains.
- Experience starting projects from scratch—perhaps as a founder, open-source contributor, or through impactful side projects.

## COMPENSATION

€50k–€90k base + Stock Options, depending on seniority level.

If you have 10+ years of experience and are looking for a higher-leverage role (broader scope, leading multiple tracks), we’re also hiring for a Senior Product Backend Product Engineer (€90k–€140k base + ESOP).

## WHERE YOU’LL WORK

We’re in Madrid (Calle Guadalquivir, El Viso), 5 minutes from Nuevos Ministerios.

No fixed schedule. We expect at least 3 days/week in the office — high-context work moves faster in person. Sam and I are often in the office, and part of our role is to be close to decisions and context.

## WHY JOIN INVOPOP

- Real ownership: you research, decide, build, ship, and support your own Apps.
- Work closely with Sam Lown (founding CTO of Cabify) and a small, high-bar team.
- Hyper-growth: 15 launches planned in 2026 and a 3x growth goal.
- Full room to experiment: leveraging AI to the infinite, switching frameworks, databases, schemas, nothing is set in stone here—as long as you can justify why.
- No bureaucracy or politics: product, taste, and ideas win over anything else

## INTERVIEW PROCESS

- Intro call (30 min)
- Take-home exercise
- Technical interview (1h)
- Final interview, in person (1h)

## About Invopop

## Company Overview
- **One-liner**: Invopop provides a single API for global e-invoicing and tax compliance, automating the conversion of sales data into locally compliant e-invoice formats for over 25 countries.
- **Entity Type**: Private (Startup, Y Combinator W23 batch)
- **Headquarters**: Madrid, Spain (with a second office in London, UK)
- **Founded**: 2020 (Y Combinator profile lists 2021)
- **Founders**: Sam Lown (Co-founder & CTO, previously Co-founder & CTO of Cabify) and Juan Moliner Malaxechevarría (Co-founder, previously a consultant at BCG)

## Core Business
- **Primary industry/industries**: E-Invoicing, Sales Tax/VAT Compliance, Fintech, B2B SaaS
- **Target customers**: B2B; global software companies, fast-growing companies, and enterprises that need to issue compliant invoices across multiple jurisdictions (e.g., SumUp, Fever, DeepL).
- **Mission or purpose statement**: "Help us make invoicing great again" and "Simplify Sales Tax/VAT compliance, globally."

## Products & Services
- **Invopop API**: A single API that receives sales transaction data in a simple, open-source format (GOBL) and converts it to locally compliant e-invoices. This includes syncing with tax authorities for real-time reporting (e-invoicing), generating custom-branded PDF invoices, and integrating with the company’s existing stack (ERP, billing, payments, reconciliation).
- **GOBL (Global Open Business Language)**: An open-source, global invoice format that Invopop is "proudly built on," designed to standardize invoice data across different countries.

## Market Standing
- **Valuation/Market Cap**: Not publicly available (private startup).
- **Key Metric**: Total Funding — Not publicly disclosed beyond being a Y Combinator-backed company (Winter 2023 batch). The Y Combinator profile lists a standard SAFE note with a valuation cap range (0.10% - 1.00%).
- **Notable Investors/Partners**: Y Combinator (W23 batch). The company website also lists individual angel investors including Maex Ament (Co-founder of RevenueCat), Jeff Epstein (Former CFO of Oracle), Mark Villacampa (Co-founder of Cabify), and others.
- **Growth Signals**: 
    - Trusted by global companies like SumUp, Fever, and DeepL.
    - Live in Colombia, Spain, Portugal, and many more countries coming soon (Mexico, Italy, Peru).
    - Team size is listed as 7 on Y Combinator (likely at time of batch) and 17 total employees on Built In, indicating recent growth.
    - The company is positioned to capitalize on a massive regulatory tailwind: over 40 countries (including all EU member states) will require real-time e-invoicing in the next 1-5 years.

## Competitive Advantages
- **Single API for global compliance**: Instead of building and maintaining numerous local integrations, companies integrate once with Invopop, saving significant time and engineering resources.
- **Open-source foundation (GOBL)**: By building on an open standard, they reduce vendor lock-in and foster a community around their format, making it easier for partners and customers to adopt.
- **Founder-Market Fit**: Co-founder Sam Lown experienced the e-invoicing "nightmare" firsthand as CTO of Cabify during its expansion into Latin America, giving the team deep, first-hand knowledge of the problem.
- **Y Combinator Backing**: Provides credibility, network, and access to a global community of startups.

## Strategic Focus
- **Global Expansion**: Rapidly adding support for new countries (Mexico, Italy, Peru, etc.) to stay ahead of the regulatory curve.
- **Product Development**: Building out the platform to handle more complex compliance scenarios and deeper integrations with customer stacks.
- **Talent Acquisition**: Actively hiring for key roles (VP of E-invoicing Compliance, Staff Backend Engineer, Founding Solutions Engineer, Founding Marketer) to scale the team and product.

## Why Work Here
- **High-Impact Problem**: Work on a critical infrastructure problem that is becoming a global necessity for any company doing cross-border business.
- **Strong Founding Team**: Learn from experienced founders who have built and scaled a unicorn (Cabify).
- **Culture & Values**: The company emphasizes values like "Seek Honesty" and "Build," fostering a team of "curious, kind, and ambitious builders" [invopop.com].
- **Work Model**: Hybrid (with offices in Madrid and London). The Built In profile notes "OnSite Workspace" with employees working from physical offices, but job postings also indicate a hybrid model.
- **Compensation**: Y Combinator profile lists salary ranges for roles (e.g., €50K - €140K EUR) plus significant equity (0.10% - 1.00%), which is typical for an early-stage, high-growth startup.
- **Engineering Culture**: Focus on backend product engineering with a modern tech stack (GOBL, API-first). The team is small (7-17 people), offering significant ownership and impact.

## Sources
1. [invopop.com](https://www.invopop.com/)
2. [invopop.com/about](https://www.invopop.com/about)
3. [invopop.com/careers](https://www.invopop.com/careers)
4. [ycombinator.com/companies/invopop](https://www.ycombinator.com/companies/invopop)
5. [builtin.com/company/invopop](https://builtin.com/company/invopop)

## Other roles at Invopop

- [Sales Development Representative](https://feeny.ai/job/sales-development-representative-invopop-madrid-c75yk8nrpj9g) — Madrid, Spain
- [Founding Solutions Engineer](https://feeny.ai/job/founding-solutions-engineer-invopop-madrid-0khd58s5hbzp) — Madrid, Spain
- [Staff Backend Product Engineer](https://feeny.ai/job/staff-backend-product-engineer-invopop-madrid-9s4pexef99vk) — Madrid, Spain
- [Graduate Product Engineer](https://feeny.ai/job/graduate-product-engineer-invopop-madrid-t75mnbpne8nt) — Madrid, Spain
- [Backend Product Engineer](https://feeny.ai/job/backend-product-engineer-monaco-san-francisco-3j4hd6hh9x5d) — San Francisco, CA
- [Backend Product Engineer](https://feeny.ai/job/backend-product-engineer-wholesail-san-francisco-tbxah649hsq1) — San Francisco, CA
- [Backend Product Engineer](https://feeny.ai/job/backend-product-engineer-tolan-san-francisco-z4m11bx650h4) — San Francisco, CA