About the Position

Senior Software Engineer - Offline

Rotterdam

Technical – R&D /

Full-time /

Hybrid

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About Us

We are a leading global software company dedicated to the world of computer aided design, 3D modeling, and simulation-helping innovative global manufacturers design better products, faster! With the resources of a large company, and the energy of a software start-up, we have fun together while creating a world-class software portfolio. Our culture encourages creativity, welcomes fresh thinking, and focuses on growth, so our people, our business, and our customers can achieve their full potential.

Position Overview

Join our Runtime & Client group as a Senior Software Engineer and help shape the future of offline-first application development. You'll work on the offline capabilities that power Mendix mobile and web apps-building the foundation that enables applications to keep running when there's no network connection. From local data storage and background synchronization to conflict resolution when devices reconnect, you'll solve complex technical challenges and make them simple for developers and non-technical users alike. Working across the full stack-client-side runtime, server-side synchronization, and developer tooling-you'll have the opportunity to connect the dots and create resilient, offline-capable experiences that matter.

Responsibilities

Design, develop, and maintain offline runtime components and synchronization layers that power Mendix applications across web and mobile platforms
Implement and optimize data synchronization strategies, including conflict detection and resolution mechanisms between offline clients and backend systems
Collaborate across the full product stack-from client-side runtime code to server-side logic to Studio Pro tooling-to deliver cohesive offline-first experiences
Mentor team members and contribute to technical architecture decisions that balance complexity with usability for developers and end users
Participate in code reviews, testing, and quality assurance to ensure robust, performant solutions that meet production standards
Stay current with emerging web technologies, offline-first patterns, and browser APIs to continuously improve our platform

Requirements

Required:

Expert-level proficiency in JavaScript/TypeScript with a strong understanding of offline-first patterns and browser storage APIs (such as Origin Private File System or service workers)
Proven experience designing or implementing data synchronization strategies, including conflict detection and resolution mechanisms
Ability to work across multiple areas of a product-from client-side runtime to server-side synchronization to developer tooling-and connect those dots effectively
Demonstrated commitment to quality and a sense of responsibility for the impact your work has on developers and end users who depend on it
Minimum 6 years of professional software development experience

Preferred:

Experience with Progressive Web Apps (PWAs) or React Native and understanding of offline challenges specific to mobile environments
Knowledge of WebAssembly (WASM), including its performance characteristics and browser compatibility constraints
Experience with JVM-based languages (Scala, Java, or Kotlin) relevant to runtime synchronization layers
Familiarity with C# or.NET, relevant to Studio Pro development
Background building or working with low-code or no-code platforms
Experience with cross-stack testing frameworks such as Jest, WebdriverIO, or similar tools

We Offer

Competitive salary range: €69,100 to €110,600
Incentive compensation
Health and wellness benefits
Opportunity to grow through real projects, strong technical peers, and global mobility
Commitment to equality and inclusion

About the Company

At Siemens Software, flexibility is how we work-hybrid by default, built on trust and autonomy. Together, 30,000 people across more than 200 countries build technology that shapes the real world. You'll grow through real projects, strong technical peers, and global mobility, backed by the scale and benefits of an industrial software leader. We're committed to equality and inclusion, and we hire based on merit, skills, and impact. Bring your curiosity and creativity and help us shape tomorrow!

Diversity & Inclusion

We value equal opportunities and welcome applications from people with disabilities. At Siemens, we believe people who've had real experiences dealing with being different will excel as leaders. Let's foster a culture of creativity and innovation. We will ensure that individuals with disabilities are provided reasonable accommodation to participate in the job application or interview process, to perform essential job functions, and to receive other benefits and privileges of employment. Please contact us to request accommodation.

Siemens Software. Transform the Everyday

#LI-Hybrid #SaaS

We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses and identifying potential inconsistencies or verification signals in application materials based on available information. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.

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Senior Software Engineer - Offline

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