Backend Developer

Backend Developer

We're growing our Dealer Portal team and looking for a Senior Backend Developer to help build a unified B2B platform that empowers our global network of retail and wholesale partners. You will play a key role in bringing these together into a single, modern portal, owning the architecture from the ground up and driving it through to production.

We are actively integrating AI and automation into all areas of the business and expect candidates with mindset focused on improving efficiency and deliver a better user experience.

Key Responsibilities

• Design and build a unified B2B dealer portal architecture from scratch, routing requests to the correct ERP systems
• Read, maintain, and progressively rewrite/migrate legacy codebase as part of the portal modernization
• Build API and FTP integrations between the unified front-end and both ERP systems
• Develop new backend features for the portal from scratch, using PHP 8+
• Own the MVP delivery end-to-end — from architecture proposal to production release
• Write clean, maintainable, and well-documented code following engineering best practices
• Optimize database queries, APIs, and caching layers to meet performance and latency targets
• Investigate and resolve production issues, implementing preventive measures to improve system stability
• Collaborate closely with the Product Owner, and EU/ US engineering teams
• Use AI tools actively as part of daily development workflow — this is a core, non-optional part of how the team works

Required Experience

• 5+ years of experience with modern PHP (8.0+) and strong knowledge of its core features and best practices
• Proven experience designing and owning backend architecture independently, without requiring detailed technical direction
• Hands-on experience with system integrations — ERP integrations, API design, FTP-based data exchange, multi-system architecture
• Ability to read and refactor/rewrite legacy Java code
• Solid experience with database design and query optimization
• Strong testing culture: unit and integration testing
• Experience with Git workflows, code reviews, and CI/CD processes
• Comfort working with legacy systems and complex, imperfect environments — this is non-negotiable for the role
• Genuine, demonstrated use of AI-assisted development tools in daily work
• English level - B2

Soft skills

• High level of ownership and courage to make and defend architectural decisions independently
• Ability to independently lead a project from design to release and long-term evolution
• Strong estimation skills and proactive risk communication
• High level of autonomy in resolving infrastructure and stability issues
• Collaborative approach and readiness for cross-functional teamwork across EU and US teams
• Comfortable operating in ambiguity on a greenfield/rebuild project

Nice to have

• Experience with Navision, AS400, or Sana Commerce
• Experience with other eCommerce platforms

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We create the world's most popular apps for playing, recording and composing music. Through our innovative learning tools, expansive music catalogs and free open-source software, we make it easier for millions — from beginners to experienced musicians — to be creative every day. Our talented team of music lovers collaborates all over the globe, from Limassol to Seoul and Boston to Berlin.

We're an ambitious company with the drive and culture of a startup — with many more exciting Muse Group developments to come. Hal Leonard, which joined Muse Group in 2023, is the world leader in sheet music publishing and music education. The company has a storied history of providing music learners with the very best methods and arrangements of popular music for over 70 years. Hal Leonard is also a major distributor of popular brands of instruments, gear, and software to the music trade worldwide.