Software Engineer - Implementation & Customer Team
About
Fynn provides companies with the infrastructure for flexible, automated billing, covering the entire Quote-to-Contract process from quoting to invoicing and debt collection. We are an established player with over 5 years in the market, having processed over 250,000 customers and sent more than 1.5 million invoices. We are a focused team dedicated to solid technology, customer orientation, and defining a new category. This is a critical phase where you can actively shape Fynn's future.
Responsibilities
As a Software Engineer in our Implementation & Customer Team, you will be the bridge between our product and our customers, ensuring successful, technically sound, reliable, and smooth onboarding for new clients. This is an engineering role with a strong customer focus, where you will handle the entire problem-to-solution lifecycle: diagnosis, implementation, and handover. Your insights will directly influence product development.
Customer Onboarding & Technical Integration:
- Accompany new customers from initial technical analysis to productive operation.
- Understand systems, clarify requirements, and ensure a smooth start on Fynn.
- Perform technical analysis of existing customer systems and data structures.
- Coordinate with customers on requirements, timelines, and handover criteria.
- Set up and verify integrations, API connections, configurations, and test runs.
Data Migrations:
- Develop and operate ETL processes for customer transitions from existing systems to Fynn.
- Analyze and map source data from legacy systems, CSV exports, or third-party APIs.
- Develop ETL pipelines with robust error handling, validation logic, and logging.
- Ensure quality assurance of migrated data, especially critical in the finance context.
Support, Bug Fixing & Further Development:
- Act as the first technical point of contact for customer issues.
- Replicate, analyze, and resolve issues, or escalate with complete context.
- Actively contribute feedback to product development based on customer interactions.
- Communicate issue status and resolutions directly with customers.
- Support the integration of new features into the existing platform.
- Conduct code reviews and ensure adherence to software development best practices.
- Create and maintain user documentation for software modules.
Requirements
We are looking for individuals who are technically sound, think independently, and enjoy solving real customer problems, rather than a perfect match to a technology list.
Skills and Experience:
- 2-4 years of software development experience, preferably in a customer-facing role (e.g., Implementation Engineer, Solutions Engineer, or Software Developer with customer contact).
- Knowledge of subscription billing, invoicing, or fintech.
- Good PHP skills, ideally with Symfony experience, and the ability to navigate an existing backend.
- Strong understanding of object-oriented development.
- Proficiency in reading and understanding our API and frontend layer (TypeScript/JavaScript) to diagnose errors.
- Solid SQL understanding for direct data problem-solving.
- Experience with data migrations or ETL processes, or a clear approach to them.
- Precision and a strong sense of responsibility, particularly in the finance context.
- Excellent communication skills, able to explain technical issues to both financial and technical audiences.
Working Style:
- Collaborative work environment with regular code reviews, joint error analysis, and open team discussions.
- Commitment to ensuring critical code has a second review, decisions are documented, and knowledge is shared within the team.
- Proficiency in using AI tools (e.g., Claude Code, Codex) to enhance focus on problem understanding, solution quality, and customer feedback.
Tech Stack:
- PHP / Symfony / PHPUnit
- TypeScript / Node.js
- PostgreSQL
- Gitlab
- Linear
- Notion