Sustainsys was founded by Anders Abel in 2017 with a clear vision: to build a sustainable business model for open source, and a workplace he would actually want to work at himself. That vision still shapes everything about how Sustainsys operates.
The library now known as Sustainsys.Saml2 has its roots in consulting work Anders did back in 2012 – years before Sustainsys was founded. By the time the company launched in 2017, the library was already widely used and became a natural foundation for the business.
Close to a decade later, the idea has proven itself. Sustainsys.Saml2 is actively maintained – without anyone having to sacrifice evenings and weekends to keep it going. It's the support agreements from our customers that make this possible, ensuring the library continues to be developed and maintained over time. For our customers, that means more than just a great library – it means a long-term partner with expert help always within reach.
Over the years, Sustainsys.Saml2 was often used alongside the popular open-source OIDC providers IdentityServer3 and IdentityServer4. When the authors of IdentityServer founded Duende Software to commercialize the product, Sustainsys partnered with them to provide support, consulting and training services to Duende's customers.
Sustainability is a core value at Sustainsys – and that extends to how we work with customers. We aim to be a long-term partner and trusted advisor, not a permanent fixture. When a project is done, we hand it over to the customer's team and move on. We don't believe in perpetually renewed full-time assignments. That said, we are always available when support is needed and happy to return to assist in new projects.
We also believe in a sustainable work-life balance. When we work, we're fully committed and professional. Outside of working hours, we're fully present for everything else that matters.
Anders Abel
Anders Abel is a senior .NET developer and the founder and CEO of Sustainsys, and one of Sweden's leading experts in Identity and Access Management. He is a long-time Microsoft MVP and the creator of the Sustainsys.Saml2 library – a widely used cornerstone for SAML2 integration on the .NET platform.
When asked what he does for a living, Anders usually gives a disarmingly simple answer: "I build login buttons." Behind that answer lies over 30 years of passion for the craft of coding, starting with his first lines of BASIC at age nine. His expertise spans OpenID Connect, OAuth2 and scalable cloud architecture – and he is a frequent speaker at international conferences such as NDC, DevSum and CPH DevFest.
Whether through his blog, Passion for Coding, or his work with OAuth2 and OpenID Connect, Anders remains dedicated to securing the web – one login at a time.
Sofia Hjerpe
Sofia Hjerpe is a junior .NET developer, with a background that spans frontend development, UX/UI design and full-stack engineering. She holds a Bachelor's degree in IT, Media and Design from Södertörn University, where she developed a broad foundation in interaction design, graphic design and frontend development.
Since graduating, Sofia has built hands-on experience across a range of technologies and environments – from frontend roles focused on Vue.js, TypeScript and React, to backend development in C# and .NET. That breadth gives her a holistic perspective on software projects that goes beyond any single layer of the stack.
At Sustainsys, Sofia is deepening her expertise in .NET and Identity and Access Management, bringing both technical curiosity and a natural understanding of the user perspective.
Hanna Hult
Hanna Hult is a junior .NET developer with a strong interest in security and backend engineering. She has hands-on experience with C# and ASP.NET Core, combined with a solid understanding of security, integration, and cloud services. She prioritizes modern development practices and maintainable code.
With a passion for problem-solving and a natural curiosity for how systems work under the hood, she thrives on technical challenges and she is eager to evolve as a developer. Her background in service and education has also given her strong collaborative skills and a natural ability to communicate and work with other people.
Suzanne Rudels
Suzanne Rudels is the COO of Sustainsys, responsible for strategy, business development, customer relations and day-to-day operations. She works closely with the CEO to ensure that the company runs smoothly and that customers are well taken care of.
She has a background in IT Service Delivery, where clear communication and long-term customer relationships have always been at the core of her work. Structured, curious and people-oriented, she naturally bridges the gap between technical experts and the broader organization – making sure both sides understand each other.
You?
Do you have experience on Asp.NET, OpenID Connect, OAuth 2.0 and Saml 2.0? Have you used Duende IdentityServer and Sustainsys.Saml2? Do you want to get great working conditions and be part of an awesome team in Huddinge, Stockholm?
Please reach out to discuss if you are our next colleague!