Ruby on Rails Backend Developer (m/w/d)

About aifinyo AG

aifinyo is a fintech company based in Dresden focusing on simplifying financial workflows for startups, freelancers, and businesses through innovative digital solutions. Their platform enables customers to manage finances, invoices, and accounting from anywhere using web-based tools. The company emphasizes a collaborative and honest work environment where team members take responsibility and actively shape the company's future.

Role Overview

We are looking for a Ruby on Rails Backend Developer to join our team in Dresden, available full or part-time (minimum 30 hours per week). Your main responsibility will be designing and implementing new features for Ruby on Rails applications while maintaining and improving existing backend systems.

Key Responsibilities

• Design and implement new features for Ruby on Rails applications and contribute to ongoing product development.
• Develop solid backend logic and maintain modern RESTful APIs for the platform.
• Write efficient SQL queries and optimize PostgreSQL databases for stability, speed, and scalability.
• Create and maintain internal administrative tools using Hotwire, Turbo, and Stimulus to support efficient internal workflows.
• Maintain and enhance existing code through refactoring and improvements.
• Support maintenance of legacy Python scripts and assist progressively migrating these to the Ruby-based system architecture.

Technical Stack

• Backend: Ruby on Rails, Python (existing scripts), PostgreSQL, REST APIs, Sidekiq for background jobs
• Frontend: Hotwire, Turbo, Stimulus, ERB Templates
• Testing & Quality Assurance: Minitest, Oaken
• Infrastructure: AWS

Candidate Profile

• Minimum of two years’ experience in Ruby on Rails development.
• Strong knowledge of SQL, particularly with PostgreSQL, capable of handling complex queries and database optimizations.
• Familiarity with modern Rails frontend technologies such as Hotwire, Turbo, and Stimulus.
• Python knowledge is a plus but not mandatory.
• Fluent German language skills for confident communication within the team.
• Adherence to Rails development principles including Convention over Configuration, Domain-Driven Design, and the Principle of Least Surprise, with a passion for writing clean, sustainable code.

Benefits and Work Environment

• Comprehensive additional benefits including company pension scheme with at least €60 monthly contribution, Edenred card worth €47 per month, minimum €1,500 annual budget for professional development, and yearly salary reviews.
• Healthy work-life balance supported by flexible working hours, hybrid remote options, part-time possibilities, and 28 days of vacation.
• A small but dynamic team of about 45 employees with regular team events and social gatherings.
• Structured onboarding process including introductions and job shadowing within teams to facilitate smooth integration.
• Opportunity to take early responsibility and actively participate in implementing new ideas to shape the company’s success.

Additional Information

Queries can be addressed to Kerstin Maul, Head of People & Culture, reachable at 0351 89693379.

Please submit applications through the company’s career page without sending Word format files for security reasons.

Personal data will be used solely for employment decision-making purposes under the stated privacy policy.