Open to opportunities

Alexander Frewein

@alexanderfrewein

Senior Java backend engineer at XiTrust building MOXIS e-signatures, integrating trust centres and co-owning releases for 400+ cloud customers.

Austria

Message

At XiTrust Secure Technologies GmbH, I build and maintain Java backend features for MOXIS, an e-signature platform that processes several thousand signatures per month. I’ve implemented handlers for five signature variants and integrated Swisscom and A-Trust trust centres.

I co-own MOXIS Cloud releases, deployments and configuration with the DevOps Team Lead, and I’m planning a new greenfield service. Since 2025, I’ve led a team of four while continuing to code; before XiTrust, I worked on cryptographic software at NXP, including implementing the X.509 certificate standard directly into an HSM.

Experience

Work history, roles, and key accomplishments

Current

Internal Automation Tooling (AI-assisted)

Current

XiTrust Secure Technologies GmbH

Jan 2026 - Present (10 months)

Built internal automations for engineering and product management, including a Jira ticket validator, ticket analyst, meeting-notes agents, and custom code-review agents. These run on Anthropic MCP and Claude Code and are used daily by the team.

Automation MCP Claude Code Agentic Code Review GenAI

Current

Senior Java Backend Developer

Current

XiTrust Secure Technologies GmbH

Mar 2023 - Present (3 years 8 months)

Develops Java backend for MOXIS e-signature platform, handling multiple signature variants and integrating trust centres. Co-owns releases and deployments with DevOps and leads a team of four while remaining hands-on.

Java Spring Boot JWT YAML Swagger Azure Artifacts Release Management Stakeholder Communication EIDAS ETSI Qualified Electronic Signature (QES)Trust Center Mentorship AI MCP

Software Developer R&D (Cryptography / HSM)

NXP Semiconductors Austria GmbH & Co KG

Jan 2018 - Dec 2022 (4 years 11 months)

Worked on cryptographic software close to chip level in an HSM environment, from low-level C/C++ to Java-side integration. Implemented the full RFC standard for X.509 certificates directly into the HSM.

C C++Java X509 PKI HSMs Cryptography SVN Maven

Education

Degrees, certifications, and relevant coursework

Graz University of Technology

MSc (Dipl.-Ing.), Software Engineering & Business

2020 - 2022

Completed a Master of Science in Software Engineering & Business with a thesis on the design and implementation of cryptographic functions of a hardware security module on smart cards.