# Mustafa Culban — Senior Backend / Full-Stack Engineer

> 8+ years building secure, scalable B2B SaaS platforms serving 400,000+ daily active users. Strong focus on backend architecture, security, and cloud infrastructure. Based in Ankara, Türkiye; relocating to Germany (Chancenkarte), open to remote and to on-site roles in Germany, the Netherlands, and Austria.

This site is the personal CV/portfolio of Mustafa Culban. A machine-readable JSON version of the full CV is available at /cv.json.

## Profile

- Role: Senior Backend / Full-Stack Engineer (also: Technical Lead, AI Product Engineer, Founder @ DevJoys)
- Location: Ankara, Türkiye
- Email: karamusluk@gmail.com
- GitHub: https://github.com/karamusluk
- LinkedIn: https://www.linkedin.com/in/mustafaculban
- Medium: https://medium.com/@mustafaculban1
- Website: https://devjoys.com
- CV PDF: https://cv.devjoys.com/Mustafa_Culban_CV_2026.pdf
- Languages: Turkish (native), English (C1), German (A1, learning)
- Education: B.S. Computer Science and Engineering, Bilkent University (2013–2018)

## Experience

- Jotform (Jan 2019 — May 2026): Senior Software Engineer / Team Lead. Led a six-person team delivering SOC 2 / GDPR-compliant two-factor authentication for ~400,000 daily users; SMTP OAuth2 modernization (Gmail, Microsoft, custom SMTP); internal growth CRM analyzing 15–20M users; latency reduction from ~400ms to 250–300ms; hired six engineers, mentored 24–25 interns.
- DevJoys (Jan 2024 — present): Founder & Product Engineer. One-person AI product studio — built and launched Tande, JuriSpy, and DroneFleetHQ; DroneFleetHQ serves eight paying customers (~$240 MRR).
- Alyo Technology / Anvato (Jan 2018 — Jan 2019): Full-Stack Developer. Live streaming and media delivery; ~20 TB traffic during a two-week Super Bowl broadcast window; encrypted HLS delivery; GCP.
- Bi'ste / Biste Soft (2019 — 2025): Founding Engineer across two startup ventures.

## Projects

- /projects/2fa: Two-factor authentication platform at Jotform — 400K DAU, SOC 2 & GDPR.
- /projects/smtp-oauth2: SMTP OAuth2 modernization — zero-downtime migration across Gmail, Microsoft, custom SMTP.
- /projects/teams: Enterprise Teams infrastructure at Jotform.
- /projects/growth-crm: Internal growth CRM analyzing behavioral signals across 15–20M users.
- /projects/dronefleethq: Drone fleet management SaaS — live at https://www.dronefleethq.com, 8 paying customers.
- /projects/tande: AI-centered social product — live on the iOS App Store, https://tandeapp.com.
- /projects/jurispy: "Kim Haklı?" — AI judge for everyday disputes. Live at https://whosrite.devjoys.com and on the App Store: https://apps.apple.com/us/app/jurispy-decision-ai/id6759007119.
- /projects/medreseai: Gamified Islamic education app with AI pronunciation assessment — in development.
- /projects/velora: In development.

## Skills

PHP · TypeScript · Node.js · React · React Native · MySQL · PostgreSQL · Redis · Elasticsearch · Kafka · RabbitMQ · AWS · GCP · Docker · OAuth2 · REST APIs · CI/CD · LLMs · RAG · Supabase · Expo

## Certifications

- Claude Code in Action — Anthropic (https://verify.skilljar.com/c/vdirg7ha9726)
- Claude Code 101 — Anthropic (https://verify.skilljar.com/c/xgfj2tx3v7ui)
- Claude Platform 101 — Anthropic (https://verify.skilljar.com/c/uu9x64d27bcp)
- Introduction to Claude Cowork — Anthropic (https://verify.skilljar.com/c/rwyx2tjwmvij)
- Claude 101 — Anthropic (https://verify.skilljar.com/c/995sfq6oyrum)
- International PHP Conference Munich 2025 — attendee (/certs/International_PHP_Conference_Munich_2025.pdf)
- Full Stack Web Development — freeCodeCamp (2016–2017)

## Optional

- /cv.json: Full CV as structured JSON
- /experience: Detailed work history
- /projects: Case studies with architecture and outcomes
- /certifications: Verified certifications
- /contact: Contact form and availability