Selahaddin I.Private profile: Upwork shows its earnings only to signed-in members, so we check it every few weeks, not daily. MRR here is a rough estimate (Upwork's six-month earnings ÷ months active). Last read Nov 5, 2026.

8+ years of expertise in developing telecommunication software and firmware solutions. Demonstrated proficiency in collaborating effectively with diverse international teams. Highly skilled in C programming in system-level development on Linux and RTOS platforms. Experienced in C++ and Go (Golang), with exposure to backend and distributed systems. *** Skills Languages: C, C++, Go (Golang), Bash, SQL System: POSIX APIs, multithreading, inter-process communication (IPC), synchronization (mutexes, condition variables), socket programming (TCP/UDP/raw sockets), memory management Backend: RESTful APIs, gRPC, GraphQL, JWT, authentication, authorization, database integration (SQL/NoSQL), message queues, telemetry, load balancing, microservices and serverless architecture. Telecom: SIP signaling, IMS (IP Multimedia Subsystem) core architecture, Online charging systems (OCS), MMTel (Multimedia Telephony) applications, RTP/RTCP media transport, STUN/TURN NAT traversal Protocols: HTTP, WS, FTP, MQTT, SIP, WebRTC, Diameter, SNMP, LwM2M, OneM2M, NETCONF, TCP, UDP, SSL, RTP, RTCP, ICMP, STUN, TURN Platforms: GNU/Linux, FreeRTOS, Zephyr OS, AWS (S3, EventBridge, SQS, Lambda), Docker, Kubernetes, OpenSIPS, Kamailio, Prometheus, Grafana Libraries: glibc, pthread, libcurl, libwebsockets, libevent, OpenSSL, mbedTLS, ncurses, freeDiameter, Gin, Fiber, Gorilla Mux, GORM, Cobra, Viper, Zerolog, Testify Tools: Git, Jenkins, Make, CMake, Go Modules, GCC, GDB, Valgrind, Wireshark, Postman, curl, strace, tcpdump, kubectl, helm