Fonoa is the Tax Operating System for autonomous tax. AI that tracks every rule, acts on every obligation, and proves every decision, built on modular infrastructure.

Fonoa’s modules cover the full indirect tax lifecycle: tax ID validation, real-time tax determination, e-invoicing, and returns. All on one shared data model and integration, with one audit trail. Each added capability makes the others stronger.

Agents monitor obligations, populate returns, catch anomalies and assemble audit packs in seconds. The system does the work. Humans make the calls. That’s autonomous tax.

We operate across 120+ countries, with clients going live in weeks, if not days.

Trusted by Canva, Netflix, Spotify, Uber, Zoom and Booking.com. Rated 4.5/5 stars and a High Performer on G2 and 4.6/5 stars on Gartner Peer Insights.

Find out more: www.fonoa.com

About Engineering at Fonoa

Engineering is central to how we build the business. We focus on solving real customer problems, not just shipping features. We work in small, high-trust teams, with full ownership across the lifecycle, from design to production and beyond.

We value:

• Ownership – engineers own what they build end-to-end

• Simplicity – we break down complex problems into clear solutions

• Thinking Big - we innovate with modern technologies (LLMs, AI Agents, etc.) to solve meaningful problems

• Quality – scalable, maintainable systems are non-negotiable

• Speed & iteration – we ship fast, learn, and improve continuously

• Collaboration – we win as a team, not as individuals

Position Overview

As Fonoa continues to scale globally, we are looking for a Software Engineer, ERP Integrations to help us build and expand integrations with complex enterprise systems used by some of the world’s largest companies.

This role sits at the intersection of product engineering, enterprise systems, and large-scale financial workflows. You will work on designing and building integrations that connect Fonoa with ERPs, billing platforms, procurement systems, and other critical parts of the enterprise ecosystem.

This is not a role focused on maintaining isolated connectors. You will work on solving complex integration challenges at scale dealing with large external APIs, inconsistent data models, reliability concerns, and evolving customer requirements. You will help shape how our platform integrates into core enterprise workflows such as Order-to-Cash and Procure-to-Pay.

You’ll work closely with engineering, product, and customers to understand how businesses operate in practice and translate those workflows into scalable, reliable product capabilities.

We are looking for someone who enjoys operating in complex environments, has strong ownership, and is excited by the challenge of building systems that sit at the core of critical financial operations.

This is a highly collaborative, hands-on role for someone who enjoys solving difficult integration problems, building robust systems, and continuously improving how enterprise systems connect and exchange data.

What You Will Do

• You are fully proficient in English. Written and spoken, we are from around the world, but we work in English.

• You have a strong sense of ownership, care about what you build, and do the right thing that serves your customers.

• You’re a builder at heart; you like the opportunity of having tons of exposure, making things work for a company long term, and having an entrepreneurial attitude toward anything that comes your way.

  • You have experience building or operating integrations with enterprise systems, such as ERPs, billing platforms, or large financial systems.

  • You understand how enterprise business processes like Order-to-Cash and Procure-to-Pay work, and how systems integrate within those flows.

  • You have hands-on experience with a single ERP or enterprise system and are motivated to apply those patterns while learning others.

  • You are comfortable working with complex external APIs and data models, and designing for reliability, scalability, and correctness.

• You ship fast, continuously, and iteratively, learning each step.

• You like to use data over opinions to make decisions. And are ok with finding the data yourself when it’s missing.

• You are comfortable with change, either in priorities, goals and deadlines. You see this more as an opportunity than a hurdle. You are also satisfied with challenging the status quo and pushing for change.

• You want to make a severe impact and are excited about working in a high-growth startup.
  

What We’re Looking For

• Fully proficient in English, written and spoken — we are a global team and work in English

• Strong sense of ownership and responsibility for what you build

• Builder mindset with curiosity, proactivity, and an entrepreneurial approach to problem solving

• Experience building or operating integrations with enterprise systems such as ERPs, billing platforms, or large financial systems

• Understanding of enterprise business processes such as:

  • Order-to-Cash (O2C)

  • Procure-to-Pay (P2P)

• Hands-on experience with at least one ERP or enterprise platform, and interest in learning others

• Comfortable working with complex external APIs, large data models, and distributed systems

• Ability to design systems with reliability, scalability, and correctness in mind

• Comfortable shipping iteratively, learning quickly, and improving continuously

• Data-informed mindset and willingness to investigate problems independently

• Comfortable operating in fast-changing environments with evolving priorities

• Excited about making a meaningful impact in a high-growth startup environment

API Documentation

For engineers, API design and structure are an important part of evaluating a role. You can explore our API and how we build products here: https://docs.fonoa.com/

Tech Stack

We use these technologies today, but we don’t hire for specific tools. We care about engineers who can understand problems, make good technical decisions, and choose the right tools for the job.

• Backend: Node.js, Go

• Frontend: React, TypeScript

• Infrastructure: GCP,, k8s, Terraform, Postgres

Note:
If you don’t think you have the full experience we’re looking for, but you could be a fit and are willing to learn, do apply anyway! We are building diverse and inclusive team.

As part of the recruitment process at Fonoa, we process your personal data in accordance with our Privacy Notice for Job Applicants. This notice explains how and why your data is collected and used, and how you can contact us if you have any concerns.