Middle/Senior Fullstack Web Engineer (Backend-Focused)

Middle/Senior Fullstack Web Engineer (Backend-Focused)

Suggested starting date: June 2026, Location: Vienna, Experience level: Mid to Senior

About us

Holloid is Austria’s most innovative startup (trend, statista), a high-tech university spin-off revolutionizing bioprocess monitoring through in-line holographic microscopy. We empower some of the world’s largest food, pharma, and water companies to "see the invisible" - enabling better decisions, cleaner processes, and next-level automation. Our core offering includes a sophisticated SaaS platform, which delivers these critical insights and analytics to our users, transforming complex data into actionable intelligence. Backed by the EIC Accelerator and growing fast, we're turning cutting-edge science into real-world tools for sustainable food production, industrial fermentation, and environmental safety.

Key responsibilities

●     Develop internal tools and customer-facing B2B SaaS web applications in a fast-growing deep tech startup

●     Take ownership of backend systems, architecture, scalability, and performance

●     Improve application reliability, maintainability, and overall system quality

●     Write clean, well-tested, and well-documented code

●     Contribute to architectural decisions and technical direction

●     Support deployment processes and CI/CD pipelines

●     Explore, prototype, and validate new technical approaches and product ideas

●     Collaborate closely with product, design, and interdisciplinary teams

Requirements

●     Several years of professional software engineering experience

●     Strong backend expertise with Node.js and Express

●     Solid experience with MongoDB and Mongoose (schema design, performance tuning, indexing), cloud infrastructure services and deployment on major cloud platforms (ideally GCP).

●     Proficiency in building and consuming REST APIs (documentation using Swagger)

●     Familiarity with containerization technologies like Docker

●     Good working knowledge of React or other frontend frameworks, Vite, component libraries such as MUI, and modern frontend development practices

●     Familiarity with data visualization libraries (e.g., Lightweight Charts or similar)

●     Familiarity with Figma and translating designs into clean, maintainable, and well-documented frontend code

●     Familiarity working with agile methodologies and Jira, comfortable working in iterative development environments

●     Experience with version control (Git) and collaborative workflows

●     Ability to design, develop, and optimize scalable and efficient cloud-based solutions for web applications.

●     Optimize applications for speed, scalability, and performance across various devices.

●     Experience developing internal tools and/or B2B applications

●     Strong problem-solving skills and ability to work independently

Nice to have

●     Experience with DevOps practices (Docker, CI/CD, cloud infrastructure such as AWS/GCP/Azure)

●     Exposure to project management or technical leadership responsibilities

●     Experience working on R&D or innovation-driven projects

●     Interest in microbiology, health, and environmental issues

●     Experience working in multidisciplinary teams in a scientific field

What we offer

●     Collaborative team setting with opportunities to learn and grow in our domain.

●     A meaningful role in a mission-driven startup with international traction

●     Ownership and autonomy in a highly interdisciplinary environment

●     See your work implemented and scaled in real-life applications

●     Close collaboration with technical founders and product leadership

●     Startup vibe, research-grade science, real-world impact

●     Minimum salary (IT collective agreement) with 3 years of experience: EUR 3,954. Overpayment depends on qualifications and experience.

How to apply

Send us a CV, a motivation letter, your references, your availability, and what else you think helps us make the right decision to hire you.

Apply to 

[email protected]