Job Title: Senior Backend Engineer 
Employment Status: Full-time
Location: Vienna, Austria - Hybrid (preferred) or Remote - EU
Compensation: competitive compensation + performance-based bonus and equity options.
Final compensation is negotiable based on experience and qualifications.
Benefits: free in-office: lunch, drinks, coffee, snacks, Wiener Linien ticket, a yearly company retreat, regular team events

Job Summary

At Ketryx, we’re on a mission to help medical software teams build secure, reliable applications that make a real difference in people’s lives. We give them the tools to automate the tough parts of compliance and quality so they can focus on what matters most: creating life-saving products with confidence.

We're looking for a Senior Backend Engineer to join our team. In this role, you’ll work on the backend of our platform, helping medical device companies get their products to market faster. You’ll take ownership of features from start to finish, designing the architecture, writing the code, and seeing everything through to production. Your work will have a direct impact on the future of healthcare technology.

This is a hybrid role in Vienna, with a minimum of three days per week spent on-site. We’re open to remote work for exceptional candidates.

About You

You’re passionate about software and making a real impact. You’re curious, enjoy solving tough problems, and love the idea of working in a fast-moving environment where you can take initiative. You’re comfortable collaborating in English with team members from different areas, and you take pride in owning projects from beginning to end. Above all, you’re excited about using technology to improve patient outcomes.

What You’ll Own & Contribute To

Database Design

Design and evolve PostgreSQL schemas, write efficient queries, apply indexing strategies, and help ensure the database remains performant and maintainable as the product grows.

Backend Development

Build new integrations between the Ketryx platform and other systems, APIs, and workflows. Contribute to improving latency, throughput, and fault tolerance across the backend stack.

Maintainable Systems

Write clean, well-tested code and contribute to standards around migrations, documentation, and testing. Help ensure the system remains easy to understand, debug, and extend.

Operational Reliability

Participate in monitoring, debugging, and incident response. Help identify performance bottlenecks and reliability issues, and contribute fixes and improvements.

Collaboration

Work closely with Product, Client Operations, Compliance, Security, and other engineers to deliver features that meet both business and regulatory requirements and resolve any technical challenges that come up

What We’re Looking For

• 5+ years of experience working as a software engineer, with strong experience in backend development
• Solid skills in TypeScript
• Strong experience with PostgreSQL: schema design, query optimization, indexing, and performance tuning
• Solid understanding of backend performance and maintainability, including refactoring and technical debt management
• Comfortable collaborating across teams and participating in technical discussions and design reviews
• Comfortable working in English and collaborating across teams

Bonus Points

• Experience with Prisma and Next.js
• Experience with GraphQL (urql or Apollo)
• Familiarity with AWS services like S3, RDS, and Elastic Beanstalk
• Familiarity with Docker and Kubernetes in production or near-production environments.
• Strong habits around testing (Jest, Cucumber, Playwright)
• Experience working in regulated industries like healthcare or finance
• Experience with Kotlin and Spring
• An interest in mentoring and helping others grow

Our Tech Stack

Frontend: TypeScript, React, Next.js, Tailwind, JollyUI
Backend: PostgreSQL, Redis, GraphQL (urql), Prisma
Testing: Jest, Cucumber, Playwright
Infrastructure: AWS (e.g. S3, RDS, Elastic Beanstalk), Sentry
Collaboration: Slack, GitHub, Figma, Jira, Confluence

Compensation

At Ketryx, we offer a competitive and transparent compensation package that reflects your experience and skills:

For candidates in Austria with 3–5 years of experience, the gross annual salary starts at €70,000+.

For candidates in Austria with more than 5 years of experience, the gross annual salary starts at €90,000+.

We offer all-in contracts, with final compensation tailored to your qualifications and experience. In addition to the base salary, our package includes a performance-based bonus and stock options, aligning your success with the company’s growth. For remote candidates, salary may be adjusted slightly based on location.

Job Title: Full Stack Software Engineer 
Employment Status: Full-time
Location: Vienna, Austria - Hybrid (preferred) or Remote - EU
Compensation: competitive compensation + performance-based bonus and equity options.
Final compensation is negotiable based on experience and qualifications.
Benefits: free in-office: lunch, drinks, coffee, snacks, Wiener Linien ticket, a yearly company retreat, regular team events

Job Summary

At Ketryx, we’re on a mission to help medical software teams build secure, reliable applications that make a real difference in people’s lives. We give them the tools to automate the tough parts of compliance and quality so they can focus on what matters most: creating life-saving products with confidence.

We're currently hiring across multiple levels for experienced Full Stack Engineers (mid-level to senior) to join our team. In this role, you’ll work on both the frontend and backend of our platform, helping medical device companies get their products to market faster. You’ll take ownership of features from start to finish, designing the architecture, writing the code, and seeing everything through to production. Your work will have a direct impact on the future of healthcare technology.

This is a hybrid role in Vienna, with at least three days per week on-site. We’re open to remote employment for exceptional candidates.

About You 

You’re someone who’s passionate about software and making a real impact. You’re curious, enjoy solving tough problems, and love the idea of working in a fast-moving environment where you can take initiative. You’re comfortable collaborating in English with team members from different areas, and you take pride in owning projects from beginning to end. Above all, you’re excited about using technology to improve patient outcomes.

Ideally you will be currently located in Vienna or Europe.

What You'll Do

• Work closely with engineers, designers, and product teams to design new features
• Own technical decisions and take features all the way from concept to launch
• Review and collaborate on code to maintain high standards across the team
• Dig into logs, metrics, and error reports to troubleshoot issues and improve the system
• Team up with our Client Operations team to resolve any technical challenges that come up

What We’re Looking For

• 5+ years of experience working as a software engineer, with strong experience in both frontend and backend
• Solid skills in TypeScript and React
• Experience building scalable web applications and a good understanding of databases (we use PostgreSQL)
• Comfortable working in English and collaborating across teams
• Experience working in an early stage, product-based start up.

Bonus Points

• Experience with Prisma and Next.js
• Experience with GraphQL (urql or Apollo)
• Familiarity with AWS services like S3, RDS, and Elastic Beanstalk
• Strong habits around testing (Jest, Cucumber, Playwright)
• Experience working in regulated industries like healthcare or finance
• An interest in mentoring and helping others grow

Our Tech Stack

Frontend: TypeScript, React, Next.js, Tailwind, JollyUI
Backend: PostgreSQL, Redis, GraphQL (urql), Prisma
Testing: Jest, Cucumber, Playwright
Infrastructure: AWS (e.g. S3, RDS, Elastic Beanstalk), Sentry
Collaboration: Slack, GitHub, Figma, Jira, Confluence

Compensation

At Ketryx, we offer a competitive and transparent compensation package that reflects your experience and skills:

For candidates in Austria with 3–5 years of experience, the gross annual salary starts at €70,000+.

For candidates in Austria with more than 5 years of experience, the gross annual salary starts at €90,000+.

We offer all-in contracts, with final compensation tailored to your qualifications and experience. In addition to the base salary, our package includes a performance-based bonus and stock options, aligning your success with the company’s growth. For remote candidates, salary may be adjusted slightly based on location.

Keywords: software engineering, software development, databases, full stack, quality, change requirement, V-Model, engineer, SaaS, customer feedback, computer science, comp sci, startup, Series A, Series B, technology, tech, software, senior engineer, lead engineer, staff engineer, principal engineer

Job title: Head of Software Testing
Employment status: Full-time
Location: Vienna, Austria – Hybrid
Compensation: Competitive compensation + performance-based bonus and equity options
Benefits: Wiener Linien ticket, yearly company retreat, regular team events, free in-office lunch, drinks & snacks

About Ketryx

At Ketryx, we’re on a mission to help medical software teams build secure, reliable applications that make a real difference in people’s lives. We give them the tools to automate the tough parts of compliance and quality so they can focus on what matters most: creating life-saving products with confidence.

The Role

As Head of Software Testing, you’ll define and execute our quality strategy, ensuring that every release of our platform meets the highest standards of safety, reliability, performance, and compliance. You’ll lead a talented team of software quality engineers, testing product features and strengthening our automated testing frameworks, and play a vital role in helping medical device companies bring high-quality technology to market faster. As a quality professional, you will have an impact on our own product that you will also use on a daily basis.

About You

You’re a proven leader in software quality who knows how to build high-performing teams and scalable testing systems. You combine a deep passion for reliability with strong communication skills and a collaborative mindset. You’re detail-oriented, enjoy uncovering edge cases, and take pride in building reliable, maintainable automated tests. You thrive in fast-moving environments where you can influence processes, improve standards, and shape product direction. Above all, you’re motivated to apply your expertise to technology that directly improves patient outcomes.

Ideally you're already located in Vienna or able to relocate quickly. Unfortunately, we are unable to support people without an existing work permit for this position in Austria at this time.

What You’ll Do

• Lead and grow the quality engineering team
• Plan and coordinate verification & validation for software releases and other testing activities
• Drive scaling up of automated testing with a team using Playwright, TypeScript, Cucumber
• Work with the team to keep CI/CD pipelines fast and reliable
• Coordinate work between different teams such as Engineering, DevOps, Product, Customer Success, and Sales, representing the quality and test engineering team
• Own verification & validation for software releases
• Apply quality principles at scale
• Perform risk management
• Prepare and field audits (IEC 62304 & co.)
• Champion a quality-first culture across product and engineering
• Define, track, and share goals and metrics for test automation & product quality, to keep leadership and stakeholders informed and to identify areas for improvement

What We’re Looking For

Must-Haves

• Extensive experience (10+ years) in software quality and testing, with at least 5 years in leadership
• Experience in a high-growth company
• Experience in establishing and running processes to improve overall quality
• Hands-on experience with TypeScript or JavaScript
• Practical experience with test automation tools such as Playwright or Cypress
• Strong knowledge of software QA methodologies, tools, and processes
• Familiarity with BDD practices, ideally using Cucumber
• Experience working in an early stage, product-based start up.

Nice-to-Haves

• Experience preparing for and managing audits
• Experience working in a regulated industry such as MedTech, healthcare, finance, automotive, or aerospace
• Experience using test case management tools such as Xray, TestRail, Azure DevOps, or HP ALM
• Experience with performance and security testing
• Knowledge of ISO 13485 / IEC 62304

Compensation & Benefits

• At Ketryx, we offer a competitive compensation package that reflects your experience and skills. The annual gross salary starts at €100,000+ based on an all-in contract. Final compensation is tailored to your qualifications and experience.
• In addition to the base salary, our package includes a performance-based bonus and stock options, aligning your success with the company’s growth.
• Lunch, snacks, and coffee provided in-office
• Annual Wiener Linien public transportation pass
• Yearly company retreat and regular team events

Keywords: quality lead, test automation engineer, QA, Verification & Validation, V-Model, change request, change requirement, regulation, feature descriptions, SaaS, customer feedback, computer science, comp sci, startup, software development, Series A, Series B, technology, software

Why Cast AI?

Cast AI is an automation platform that operates cloud-native and AI infrastructure at scale. By embedding autonomous decision-making directly into Kubernetes and cloud environments, Cast AI continuously optimizes performance, reliability, and efficiency in production.
The old way doesn't work. As Kubernetes and AI environments grow, manual decisions don’t. Cast AI replaces tickets, alerts, and manual tuning with continuous automation that adapts infrastructure as conditions change. Efficiency and cost savings follow naturally from that automation.
Over 2,100 companies already rely on Cast AI, including Akamai, BMW, Cisco, FICO, HuggingFace, NielsenIQ, Swisscom, and TGS.

Global team, diverse perspectives

We're headquartered in Miami, but our impact is international. We take a global and intentional approach to diversity. Today, Cast AI operates across 34 countries spanning Europe, North America, Latin America, and APAC, bringing a wide range of perspectives into how we build and lead.

Unicorn momentum

In January 2026, we achieved unicorn status with a strategic investment from Pacific Alliance Ventures, the corporate venture arm of Shinsegae Group (a $50+ billion Korean conglomerate). Our valuation now exceeds $1 billion, and we're just getting started.

Join us as we build the future of autonomous infrastructure.

About the role

Throughput. Latency. KV cache utilization.

Move those three numbers in the right direction, and two things happen: customers get faster, cheaper inference, and our margins improve. That's the entire thesis of this role. Every kernel you tune, every quantization scheme you ship, every scheduler tweak you land shows up directly in a customer's p99 and on our P&L.
This is a high-impact seat. It is also a high-autonomy seat as you'll be given the room to lead the technical direction of inference optimization at Kimchi, not execute someone else's roadmap.

The problem: running LLMs in production is a moving target. The "right" model and serving configuration for a workload depend on traffic shape, sequence-length distribution, batch dynamics, GPU SKU, memory bandwidth, quantization tolerance, and a dozen other variables that shift week to week. Most teams pick a model once, over-provision GPUs, and absorb the cost. Kimchi is the system that makes that decision automatically - continuously matching workloads to the most cost-efficient, best-performing LLM and serving configuration on a customer's infrastructure. We're building the optimization layer between the model and the hardware, and we need engineers who understand both sides deeply.

Stack

Python; vLLM; SGLang; TensorRT-LLM; PyTorch; CUDA-adjacent tooling; Kubernetes; gRP; ClickHouse; PostgreSQL; GCP Pub/Sub; AWS / GCP / Azure; GitLab CI; ArgoCD; Prometheus; Grafana; Loki; Tempo.

Requirements:

• 5+ years building real ML systems, with a portfolio that shows depth in inference or training infrastructure (not just model training notebooks).
• Strong Python - production services, not scripts.
• Hands-on experience with at least one of vLLM, SGLang, or TensorRT-LLM, and a working mental model of why an inference engine performs the way it does on a given GPU.
• Fluency with quantization tradeoffs - you've measured quality regressions, not just compression ratios.
• Comfort with distributed systems: collective communication, sharding strategies, and the practical failure modes of multi-GPU and multi-node setups.
• A bias toward measurement. You instrument before you optimize, and you can tell the difference between a real win and a benchmark artifact.
• Self-direction. This role comes with a wide mandate; you should be excited by that, not unsettled by it.

Responsibilities:

• Push throughput. Continuous batching, speculative decoding, chunked prefill, kernel-level tuning across vLLM, SGLang, and TensorRT-LLM. Find the ceiling on each GPU SKU, then raise it.
• Cut latency. Attack TTFT and TPOT separately. Profile, identify the actual bottleneck (compute, memory bandwidth, scheduling, networking), and fix it - not the bottleneck you assumed.
• Get more out of the KV cache. Paged attention, prefix caching, eviction policies, cache reuse across requests, quantized KV. This is where a lot of the unrealized throughput lives, and it's an area you'll own.
• Quantize without regressing quality. INT8, INT4, FP8 across weights, activations, and KV. Empirical work: measure quality on real workloads, not just perplexity benchmarks.
• Shrink cold starts and memory footprint. Faster init, smarter weight loading, tighter memory accounting - the difference between a model that scales and one that doesn't.
• Scale across nodes. Distributed inference topologies, network-aware placement, checkpointing strategies that don't bottleneck on storage or interconnect.
• Set the technical direction. Decide what we benchmark, what we adopt, and what we build ourselves. Bring the team along with strong writeups and reproducible experiments.

What’s in it for you?

• Competitive salary (depending on the level of experience).
• Enjoy a flexible, remote-first global environment.
• Collaborate with a global team of cloud experts and innovators, passionate about pushing the boundaries of Kubernetes technology
• Equity options.
• Get quick feedback with a fast-paced workflow. Most feature projects are completed in 1 to 4 weeks.
• Spend 10% of your work time on personal projects or self-improvement. 
• Learning budget for professional and personal development - including access to international conferences and courses that elevate your skills.
• Annual hackathon to spark new ideas and strengthen team bonds.
• Team-building budget and company events to connect with your colleagues.
• Equipment budget to ensure you have everything you need.
• Extra days off to help maintain a healthy work-life balance.

Hiring process

• Screening call with Recruiter
• Hiring Manager interview
• Technical interview (system design)
• Live coding
• Culture Check interview with an executive

As part of our standard hiring process, we would like to inform you that a background check may be conducted at the final stage of recruitment through our third-party provider, Checkr.
Please note that Cast AI does not provide any form of visa sponsorship/work permit.

#LI-Remote

ROLE OVERVIEW

Quantitative Engineer

We are seeking a Quantitative Engineer to help build and enhance our research infrastructure and improve our existing suite of models. The ideal candidate is a mid-level engineer with extensive software development experience in a highly data-driven industry such as finance, technology, or machine learning. The ability to collaborate across teams and support multiple projects is essential.

RESPONSIBILITIES

• Design scalable systems to support Massar’s quantitative research program.
• Develop high-performance platforms for quantitative research.
• Write comprehensive documentation and conduct code reviews.
• Promote and uphold firm-wide best coding practices.

REQUIREMENTS

• Degree in computer science or a related field.
• Development experience with AWS or other cloud providers.
• 2+ years of Python experience, including proficiency with libraries such as NumPy, Pandas, PyTorch and TensorFlow.
• Excellent communication skills, self-starter, quick learner, positive attitude, and team player
• Experience in at least one of the following areas:
• Econometrics, factor analyses, or automated trading.
• Weather data modeling.
• Machine learning techniques, such as neural networks.
• Robotics and/or sensor networks.
• Other high-dimensional, computationally intensive data problems. 

COMPENSATION

The all-inclusive salary for this position STARTS at EUR 95.000,00. Competitive and performance-based compensation package, depending upon qualifications.