Senior Backend / Fullstack Engineer (Go)

Company: FunnelFox Employment type: FULL_TIME

FunnelFox is a no-code platform that helps app developers grow revenue through web2app funnels. Launched two years ago as Adapty’s new project, it’s already showing impressive growth. Marketers and product managers can build, launch, and optimize funnels in hours instead of months, all without writing a single line of code.

We are looking for a Senior Fullstack Engineer to join our Payments team. This team owns everything related to payment infrastructure inside FunnelFox: checkout flows, payment provider integrations, and the systems that make payments reliable, scalable, and flexible for our clients.

This is a highly autonomous role in a fast-moving startup environment. You will work on complex integration-heavy problems, collaborate closely with product and engineering, and help shape technical solutions in areas where requirements are often evolving rather than perfectly predefined.

In this role, you will:

• Build and improve integrations with payment service providers (PSPs) and external payment systems.
• Work on checkout infrastructure, payment flows, and backend reliability.
• Design and maintain backend logic for integrations, async processes, webhooks, and related systems.
• Participate in technical discovery and decomposition of business requirements.
• Collaborate closely with Product, Support, and Engineering on shaping solutions, not just implementing tickets.
• Investigate and resolve production and payment-related issues.
• Contribute to improving internal engineering quality, reliability, and scalability across the payments domain.
• Work in an environment with high ownership, evolving priorities, and a strong focus on practical impact.

You will be a great fit, if you have: