Stefan Streichsbier
CTO & Co-Founder at GuardRails
Oregon, Singapore
Summary
🤩
Rockstar🎓
Top SchoolStefan Streichsbier is a cybersecurity-focused technology leader and co-founder who has spent two decades evolving from hands-on penetration tester to CTO, specializing in secure web and mobile application development. He founded GuardRails to eliminate security bottlenecks by orchestrating open-source tools and surfacing actionable findings directly in pull requests, enabling developer-friendly DevSecOps. Stefan blends deep AppSec expertise with practical engineering—he teaches, speaks, and runs workshops while also contributing code, notably integrating multiple LLM providers and tooling support into projects like promptfoo to advance red-teaming and LLM security testing. Based between Oregon and Singapore, he has helped build regional DevSecOps communities and organized major events such as DevOpsDays and DevSecCon Asia. Known for championing source code analysis and secure coding best practices, he focuses on giving engineers "security superpowers" through automation and LLM-enabled tooling.
12 years of coding experience
15 years of employment as a software developer
High School, High School at St. UrsulaBSc. Computer & Information Security, BSc. Computer & Information Security at University of Applied Sciences Hagenberg
Thai, English, German
Stackoverflow
1reputation
0reached
0answers
0questions
Github Skills (11)
api10
integrate10
anthropic10
apidoc10
azure-openai10
llm10
prompt-engineering9
cirrus-ci8
cicd8
circleci8
testing7
Programming languages (14)
Github contributions (5)
promptfoo/promptfoo
Sep 2023 - Aug 2024
Test your prompts, agents, and RAGs. Red teaming, pentesting, and vulnerability scanning for LLMs. Compare performance of GPT, Claude, Gemini, Llama, and more. Simple declarative configs with command line and CI/CD integration.
Role in this project:
Back-end Developer & API Integrator
Back-end Developer & API IntegratorContributions:1 review, 10 PRs, 12 comments in 11 months
Contributions summary:Stefan primarily focused on enhancing the project's capabilities by integrating support for various Large Language Model (LLM) providers, including Azure OpenAI, Mistral, and Anthropic. They added features such as response format support for Azure and JSON mode for Mistral. Additionally, the user updated model pricing and incorporated new models, such as those from Mistral and Anthropic's Claude 3 family, showing an active role in provider integration and model management. The user also contributed to integrating the AI21 Labs provider, further extending the project's compatibility.
cici-cdcicdevaluationevaluation-framework
guardrailsio/guardrails-engine-output-schema-validator
Aug 2018 - Mar 2021
Schema Validator for GuardRails Engines
Contributions:1 review, 14 commits, 2 pushes in 2 years 6 months
guardrailsschema-validatorvalidationschema-validationvalidator
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