Senior PHP Backend Engineer

Join IOSOSO’s development team and help shape the Invitario platform — a leading B2B SaaS solution transforming how organizations engage stakeholders through virtual, hybrid, and live events.

Invitario empowers marketers and event professionals with powerful automation, seamless data integration, and enterprise-grade performance. The platform is used by enterprise and SME clients in the DACH region and supports thousands of event participants every year, giving customers a clear, efficient, and reliable way to manage invitations, participants, and event workflows across the entire event lifecycle.

And that’s where you come in.

Your Role

We’re looking for a Back-End Developer to join our Development team and enhance the backend systems powering the Invitario platform.

We seek someone who improves established systems, builds reliable APIs, supports integrations, and writes clean, maintainable code. You’ll tackle backend challenges that impact product stability, delivery speed, and platform quality.

You’ll join an agile engineering team with contributors from Austria, Bulgaria, Kosovo, and Indonesia, featuring high ownership, direct access to decision-makers, low bureaucracy, and close collaboration with the Product team.

If you enjoy solving complex backend problems, improving structure, and seeing your work reflected in a real SaaS product, we’d be glad to meet you.

Key Responsibilities

• Design, build, test, and maintain backend services, APIs, and business logic.

• Improve existing backend systems with a focus on reliability, performance, and maintainability.

• Work with databases, data models, migrations, and SQL queries.

• Investigate and resolve bugs, technical issues, and production-related problems.

• Support integrations with internal platform components and external systems.

• Write automated tests and participate in code reviews.

• Actively collaborate with Product, Frontend, QA, and Customer Success Teams.

What we are looking for

• 5 years of professional backend development experience, preferably in PHP.

• Proven experience with PHP 8.

• Hands-on experience with Symfony and/or Laravel frameworks.

• Solid experience with SQL and relational databases, ideally PostgreSQL.

• Proven record in API development and maintenance.

• Experience with unit testing, preferably with PHPUnit.

• Strong debugging and problem-solving skills.

• Practical, product-oriented mindset toward code quality, refactoring, and maintainability.

• Clear communication style through proactive ownership.

• Fluent in English, both written and verbal.

Nice to Have

• Experience with Docker-based development workflows.

• Familiarity with TypeScript.

• Understanding of jQuery or legacy frontend components.

• Knowledge of AWS or cloud-based infrastructure.

• Experience with external integrations.

We Offer

• A high-ownership Product role in a profitable SaaS organisation with a real and established platform.

• Remote-first setup, with the option to work from an office at a later stage

• Full compliance with local legislation and employment contracts through EoR partner

• Participation in team events and company gatherings in Austria

• 12 days of paid leave per year

• Laptop of choice (Mac or Windows)

If this sounds like your next step, we’d be happy to receive your CV in English.