mesutcan.dev

Mesut Can · hands-on engineering leader & technical architect

Systems that stay up when thirty million people sign in.

Engineering leader building event-driven distributed systems at 30M+ user scale. Fifteen years in the Java / Spring ecosystem. Based in Hannover, Germany.

Open to new opportunities HANNOVER, DE · 52.37°N 9.73°E
Experience 15+ yrs in the Java ecosystem
Peak scale 30M+ users on one telecom platform
Surface area 40+ systems connected to its CRM

Selected systems

  1. Real-time sensor fusion for command & control

    A sensor-fusion platform for tactical command and control. It ingests telemetry from 600+ drones together with radar and geospatial data, and sustains 200K messages a second. I designed the event-driven backend (Java 25, MQTT, TimescaleDB) and I own the IAM layer: Keycloak SSO with OAuth2/OIDC and attribute-based access control across all services.

    • identity & access
    • event-driven
    • Java 25
    • 200K msg/sec
    NATO ACT Innovation Hub defense · C2 systems · 2025 — now

  2. AI moderation for 300K+ daily comments

    CMT moderates 300K+ comments a day in real time for major media organizations, across five social platforms. I architected it on Azure Container Apps, Event Hub and Cosmos DB, with a second deployment on GCP. At the same time I was leading up to 20 engineers spread over four client projects.

    • Azure
    • event-driven
    • AI
    • up to 20 engineers
    Appsfactory media tech · 2022 — 2025

  3. Atlassian Marketplace portfolio, 1,000 → 3,000+ customers

    I set technical direction for four Atlassian Marketplace products while the customer base tripled to 3,000+ across 50+ countries. Led a team of 10 through the whole lifecycle of Delegation for Jira. Rebuilt a legacy Connect app as React microfrontends, about 50K lines of refactoring, later ran the Connect-to-Forge migrations, and added WAF, OWASP Top 10 remediation and SAST/DAST scanning for enterprise customers.

    • product
    • SaaS
    • security hardening
    • 50+ countries
    OBSS enterprise SaaS · 2020 — 2022

  4. Vessel traffic system for maritime monitoring

    Havelsan's vessel traffic system fuses GPS, radar and AIS for live maritime monitoring; I built it as Spring Boot microservices on Kafka. Adding Hazelcast caching cut peak response times by up to 60%. I also wrote simulation code for the Hürkuş training aircraft: combat maneuvers and fuel optimization.

    • Kafka
    • real-time
    • Hazelcast
    Havelsan defense · maritime · 2018 — 2020

  5. Monolith to microservices at 30M subscribers

    Led the migration of Türk Telekom's legacy monolith to event-driven microservices on Kafka and Kubernetes, serving 30M+ subscribers. I also owned the integrations between a 25M+ user CRM and more than 40 external systems, including identity, billing and provisioning.

    • EDA
    • Kafka
    • Kubernetes
    • 40+ integrations
    Türk Telekom · Innova telecom · 2011 — 2018

  6. Location-based job marketplace, zero to 100K+

    Co-founded a location-based job marketplace and built it as the lead engineer. The Android app passed 100K downloads.

    • 0 → 1
    • founding engineer
    Side project startup · 2016

Career log

  1. 2025 — now
    NATO ACT Innovation Hub Lead Software Engineer

    Real-time sensor-fusion C2 platform; owns the IAM layer

  2. 2022 — 2025
    Appsfactory Associate Technical Lead

    4 concurrent client projects + 1 product; teams totaling up to 20 engineers

  3. 2020 — 2022
    OBSS Technical Lead

    Atlassian Marketplace portfolio, 1,000 → 3,000+ enterprise customers

  4. 2018 — 2020
    Havelsan Senior Software Engineer

    Vessel Traffic System for maritime monitoring; military flight simulation

  5. 2016
    Side project Co-Founder & Lead Engineer

    Location-based job marketplace — 100K+ Android downloads

  6. 2011 — 2018
    Innova · Türk Telekom Software Engineer → Senior → Consultant

    30M+ subscriber platform, monolith → event-driven microservices

  7. 2011
    Izmir Institute of Technology BSc Computer Engineering

    Erasmus exchange: Universität Paderborn (2010)

Operator's note

I'm an engineering leader and architect. For 15 years I've built event-driven Java platforms, mostly in defense, national telecom and enterprise SaaS, where downtime and security holes cost real money. Right now I'm at NATO's Innovation Hub, where I architect a real-time sensor-fusion platform and own its authentication and authorization stack (Keycloak, OAuth2/OIDC, ABAC).

Earlier I moved a telecom platform with 30M+ subscribers off its legacy monolith, grew an Atlassian product line to 3,000+ customers, and led teams of up to 20 engineers. I still write production code. Based in Hannover, Germany.