Japan-experienced  ·  Real-time voice  ·  Worldwide

Senior Software Engineer — real-time voice systems, iOS, and backend.

20+ years of production software; 11 years of Japan-based engineering.

GitHub LinkedIn Projects
20+ years of production software 11 years in Japan Real-time audio & voice iOS & backend

About Nesim

Coding since childhood; 20+ years professionally, across real-time systems, mobile, backend, frontend, and AI-enabled products.

Most of my recent work is real-time voice: push-to-talk pipelines, PCM streaming, jitter buffers, and low-latency media over WebRTC and LiveKit. Alongside that, native iOS in Swift and SwiftUI, and backend systems in Node.js/TypeScript, C#, Elixir, and Python. My work usually sits close to the product architecture: system design, delivery tradeoffs, security risks, team practices, and the decisions that determine whether software remains reliable after launch.

I've shipped apps to the App Store and Google Play, built real-time audio pipelines, IPTV systems, social networks, AI-powered products with multi-LLM architectures, and Kubernetes management platforms. My background includes Technical Architect, Security Champion, and team lead responsibilities across production software.

I spent 11 years living and working in Japan. That experience shaped a calm, direct, detail-oriented engineering style built around reliability, clarity, maintainability, thoughtful architecture, and software that survives real users — not just demos.

Commercial and consulting work runs through my studio, Kodart OÜ (Estonia).

20+ Years in software engineering
11 Years living and working in Japan
4 Core domains: realtime, iOS, backend, AI
1M+ Users on a product I built end-to-end

Projects

Professional Highlights

RotaTalk

Real-Time Voice · AI · Mobile · Full-Stack

RotaTalk is a real-time voice platform for truck drivers: hands-free push-to-talk over LiveKit, sub-200ms end-to-end latency, multi-region SFU and TURN deployment. Around the voice layer sit a driver social feed for road intelligence, a live map with opt-in location sharing, and private team channels for fleet coordination — with Node.js & Elixir backends behind them.

RotaBot, the built-in AI road assistant, handles truck-safe routing via TomTom, HERE, real-time traffic & roadworks, fuel price comparison, and border crossing intelligence — powered by a multi-LLM agentic backend (Gemini, ChatGPT, Claude) with automatic fallback, per-provider budget controls, Redis-backed cost tracking, and SSE streaming to mobile. Available in 11 UI languages, 187 conversational languages. Live on the App Store and Google Play.

LiveKitWebRTCNode.jsElixirFlutterSupabaseTomTomHEREGeminiChatGPTClaudeRedisDockeriOS & Android

Mekanist.net

Social · Full-Stack

A social venue search engine with 1M+ registered and active users, later acquired by Zomato. Built the entire stack end-to-end: backend, frontend, admin panel, and iOS & Android applications.

iOSAndroidBackendFull-Stack

Paravi

Streaming · Android

Japan's internet television streaming service. Android Lead Engineer in a team of 3. Managed complex API integration, high-volume JSON data processing, and high-performance UI rendering under heavy load.

AndroidJavaIPTV Streaming

Send Anywhere

iOS · Architecture

Large-scale file transfer application. Joined as iOS Architect, defining the iOS architecture from the ground up and leading development of the platform's new iOS product.

SwiftSwiftUIiOS Architecture

NTV Spor

Web · Full-Stack

The #1 sports website in Turkey. Led a team to rebuild the platform from scratch for the 2010 FIFA World Cup using .NET 4.0. Architecture still in use today. Won 8+ national awards.

ASP.NET MVCC#WCFSQL

Caffè Nero Turkey

Mobile · Backend

Transformed a paper loyalty card into a full digital system — solo, in 4 months. Delivered iOS & Android apps, backend API, and Microsoft Dynamics CRM integration for an international coffee chain.

iOSAndroidC# .NETMS CRM

Turkcell TV+

IPTV · Node.js

IPTV platform for Turkey's leading GSM operator. Built a real-time log analysis tool in Node.js using regex pattern matching on syslog to detect and surface bugs instantly for the development team.

Node.jsIPTVReal-Time

TatilSepeti.com

E-Commerce · Web

Turkey's top travel booking platform for hotels, flights, and tours. Rebuilt from scratch with a 3-person team. Architecture still in use today. Won 4+ national awards.

ASP.NETC#SQL Server

SpoTribe

Social · Flutter

Location-based social networking app where users check-in and post media. Senior Engineer on both backend (Firebase) and mobile (Flutter). Also served as Security Champion for the product.

FlutterDartFirebase

Rainkube

DevOps · Platform

An internal Kubernetes cluster management platform. Developed the distributed lock mechanism using Redis Redlock and built a complete billing system from scratch. Backend & Frontend Engineer.

Node.jsVue.jsMongoDBRedis

Carada

Healthcare · Backend

Personal healthcare monitoring system with two-way device sync, concurrency-safe architecture, and real-time chat via SignalR. Backend Lead Engineer in a team of 4.

ASP.NET MVCC#SignalRMSSQL

Open Source Contributions

Countly — iOS SDK

Open Source · Analytics

Contributed to the #1 open-source mobile analytics platform, used by billions of devices worldwide. Fixed iOS SDK bugs, added concurrency features, and provided UX feedback that shaped the Countly Cloud platform.

Objective-CSwiftiOS SDK

Periodum

Open Source · Education

Active contributor to this non-profit interactive periodic table with 400+ GitHub stars. Contributes to the backend and open-source community management for the educational science project.

BackendOpen Source

Personal Projects

CoThings

Open Source · Real-Time

Open-source real-time counter for shared spaces, built during COVID-19 to help people avoid crowded areas. Full-stack: Elixir/Phoenix backend and SwiftUI iOS app.

ElixirPhoenixSwiftSwiftUIOpen Source

SnapTix

AI · iOS

AI-powered expense tracker with OCR receipt scanning. Integrates Apple Vision Kit for text extraction and OpenAI for automatic expense categorization and tax deduction assistance.

SwiftiOSDjangoOpenAIOCR

Whispeer

Security · Messaging

End-to-end encrypted, auto-expiring messaging platform. Client-side AES (CBC + PBKDF2) encryption ensures messages are never stored or transmitted in plaintext.

Node.jsVue.jsPostgreSQLAESOpen Source

Exploristo

iOS · Location

iOS app that recommends cafes, restaurants, and points of interest along your route. Preference-based filtering via Google Maps API. Built with Swift, SwiftUI, and a Node.js backend.

SwiftSwiftUINode.jsMaps API

Skills

Real-Time & Audio

Push-to-Talk, PCM streaming, jitter buffers, WebRTC, LiveKit, TURN servers, low-latency media pipelines

Mobile

iOS (Swift, SwiftUI, UIKit, RxSwift), background audio, offline-first, platform channels; Android (Java, Kotlin); Flutter & Dart

Backend

Node.js / TypeScript, C# / ASP.NET, Elixir & Phoenix, REST APIs, microservices, Supabase, real-time systems

AI & LLM

Agentic tool-calling, OpenAI, Gemini, Anthropic, OCR (Vision Kit), multi-LLM fallback, budget controls, SSE streaming, eval frameworks

DevOps

Docker, Kubernetes, Fly.io, Caddy, GitHub Actions CI/CD, Redis (Redlock), Linux, multi-region deployments

Architecture

Clean Architecture, domain-driven design, modular layering, scalable system design, Security Champion

Databases

PostgreSQL, MySQL, MSSQL, MongoDB, Redis, Firebase, Supabase (RLS)

Frontend

Vue.js, HTML / CSS / JavaScript, responsive design

Contact

Happy to talk about real-time audio, iOS, or backend work.

contact@nesimtunc.com GitHub LinkedIn