Srdjan Obucina, Developer in Belgrade, Serbia
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Srdjan Obucina

C++ and Blockchain Developer

Belgrade, Serbia

Toptal member since August 5, 2019

Expertise
DebuggingFirmwareLinuxCC++SQLUbuntuPostgreSQLFFmpegMultithreadingData EngineeringBluetoothDelphiGitArduino
Bio

Srdjan is a senior software engineer and systems architect with 18+ years of experience designing production systems end-to-end - from custom electronics and firmware up to backend services, mobile apps, and web frontends. He specializes in C/C++ systems engineering, firmware, and hardware/software co-design, with working depth across blockchain, multimedia streaming, and full-stack product development. Known for absorbing unfamiliar codebases quickly and taking full ownership of what he ships.

Portfolio

Bit & Pin
Amazon EC2, Amazon Route 53, Android, Boost, C, C++, CMake, Linux, Ubuntu...
Hawle Service GmbH
Embedded C, LoRa, Zephyr, Embedded Systems, C, Bluetooth
Integrated Communication Technologies, Inc. (via Toptal)
C++, Cross-platform, TCP/IP, Non-blocking I/O, POCO C++, Embedded Systems, XML...

Experience

  • Linux - 10 years
  • C - 10 years
  • C++ - 10 years
  • Embedded C - 10 years
  • Embedded C++ - 10 years
  • Blockchain - 8 years
  • Rust - 3 years
  • Substrate - 3 years

Preferred Environment

Git, GCC, Linux, LLVM, Visual Studio Code (VS Code), Windows, Visual Studio

The most amazing...

...thing I've coded is a video-streaming library, which brings favorite TV shows to millions of users.

Work Experience

Principal Engineer

2017 - PRESENT
Bit & Pin
  • Founded and operate Bit & Pin, a software engineering company delivering systems architecture, embedded firmware, blockchain solutions, and full-stack product development.
  • Architected and shipped a full-stack IoT platform spanning ESP32-S3 firmware, a Flutter mobile app, a C++ desktop application, a React web portal, and a network simulator — all as the sole engineer.
  • Designed a plugin-based industrial-grade authentication platform in C++17, with PostgreSQL via libpqxx, async Boost.Beast I/O, and runtime `.so` route handlers — passed an external conformance test suite.
  • Built a four-library HLS streaming ecosystem in pure C (parser, client, server, segmenter) with the M3U8 parser at 100% test coverage and FFmpeg-based multi-bitrate transcoding.
  • Designed a C++23 slot machine mathematics engine and wxWidgets-based GUI tester with hook-based composable game mechanics, RTP generation, and Markov-chain state analysis.
  • Architected Harbin, a Substrate-based blockchain platform in Rust with custom pallets, a ZKP verifier, and a dual smart contract engine (EVM + WASM).
Technologies: Amazon EC2, Amazon Route 53, Android, Boost, C, C++, CMake, Linux, Ubuntu, Yandex Cloud, wxWidgets, SDL, PostgreSQL, HTTP Live Streaming (HLS), Substrate, Parity Polkadot, ESP32, ESP12, Flutter, Gaming, Casino Games, Casinos & Gaming, Rust

Embedded C Dev for ISP4520-Based LoRa Firmware Development

2025 - 2025
Hawle Service GmbH
  • Conducted a hardware design review of a LoRa+BLE monitoring device, analyzing the schematic for a Nordic ISP4520 SoC, DC/DC buck converter, capacitive sensor, accelerometer, and other accompanying components.
  • Performed a file-by-file firmware source code audit on a Nordic nRF5 SDK codebase, identifying strong and weak points in the codem, diagnosing concurrency and reliability risks.
  • Delivered a 40-day milestone-based remediation roadmap with service-oriented firmware restructuring, sensor integration, retry/back-off LoRa messaging, alarm system, and a fully buildable, CI-ready project.
Technologies: Embedded C, LoRa, Zephyr, Embedded Systems, C, Bluetooth

Software Engineer

2019 - 2022
Integrated Communication Technologies, Inc. (via Toptal)
  • Built a communication protocol translator for hospitality-industry hardware supporting RS-232, TCP, and RPC.
  • Targeted multiple industry standard communication protocols.
  • Provided ability to achieve over 1,000 device-to-device translation combinations.
Technologies: C++, Cross-platform, TCP/IP, Non-blocking I/O, POCO C++, Embedded Systems, XML, Boost.Asio, CMake

PostgreSQL expert to work on a data transitioning project

2021 - 2021
Privacy Brain Technologies LLC (via Toptal)
  • Migrated a client's production database from Airtable to PostgreSQL on Heroku, evaluating the existing schema, eliminating duplicated data and transitive dependencies, and normalizing the model to third normal form.
  • ecreated Airtable automations as PostgreSQL stored procedures, triggers, and views, replacing formula, rollup, and lookup fields with first-class server-side logic that runs deterministically inside the database.
  • Mapped Airtable field types onto strict PostgreSQL constructs — numeric precision, TIMESTAMPTZ, junction tables for multi-select, FK constraints for linked records — and added the indexes and integrity constraints the no-code base never had.
  • Set up PostgREST as the API layer and designed role-based PUT/GET permission policies, using PostgreSQL roles and row-level security to enforce per-scenario access control directly in the database.
  • Delivered a 300% query performance improvement and unblocked advanced scenarios — joins, transactions, complex reporting — that the original Airtable proof-of-concept could not support.
Technologies: SQL, PostgreSQL, PostgREST, Database Modeling, Databases, Heroku, Airtable

Blockchain Core Developer

2019 - 2020
Peerplays Blockchain Standards Association (via Toptal)
  • Developed a Bitcoin sidechain handler for processing Bitcoin transactions on the Peerplays blockchain network, enabling two-way peg—a bidirectional transfer of assets between Bitcoin and Peerplays network.
  • Developed blockchain-based random number generator and API for accessing it. RNG is certified by Gaming Laboratories International (GLI®)—a major gaming industry provider of testing and certification services for regulators, suppliers, and operators.
  • Implemented NFT (non-fungible token) on Peerplays blockchain network, based on the Ethereum ERC721 standard.
  • Participated in the effort to benchmark Peerplay's blockchain network using Hyperledger Caliper.
Technologies: Object-oriented Programming (OOP), Object-oriented Design (OOD), Boost, Linux, JavaScript, Graphene, GitLab CI/CD, GitLab, GitHub, GCC, Docker, CMake, C++, Bitcoin, GNU Debugger (GDB), Debugging, Blockchain

Software Engineer, Freelance

2014 - 2019
Happybet SL (via Bit & Pin)
  • Designed and developed software for electronic roulette, certified, and deployed in three countries.
  • Designed and developed a system for tracking money flow, game history, and diagnostic reports used to monitor more than 200 roulette player seats in three countries.
  • Designed and developed a system for collecting and reporting player payments info to the government taxation office, in accordance with local laws.
  • Implemented communication protocols for more than ten devices used in gaming terminals, some of them custom-designed.
  • Implemented a remote administration system, used for software updates, operating system configuration, and remote support for service personnel.
Technologies: TCP/IP, Object-oriented Programming (OOP), Object-oriented Design (OOD), Relational Database Design, OpenVPN, SQL DDL, SQL, Bash Script, GCC, Amazon Route 53, Amazon EC2, Ubuntu, wxWidgets, SDL, PostgreSQL, C++, C, Data Engineering, GNU Debugger (GDB), Debugging, Raspberry Pi, Firmware, Embedded Systems

System Software Engineer

2011 - 2016
RT-RK Institute for Computer Based Systems
  • Provided software development services and on-site support for foreign partners using Marvell SoC-based platforms, focused on system programming for Android, audio/video streaming (digital TV, IPTV, audio/video playback and encoding/decoding, etc.).
  • Improved Android multimedia framework support for more audio and video formats, used by multiple set-top boxes of different manufacturers.
  • Implemented, from scratch, HLS video streaming library used by millions of users in set-top boxes and mobile phones to bring favorite multimedia content to the screen.
  • Ported Marvell Wi-Fi Display stack from x86 to ARM-based Marvell Berlin SoC platform to get a prototype Set Top Box with Wi-Fi display support.
  • Passed Google TV system integrator training, and became one of only 16 certified Google TV system integrators in the world.
  • Improved LLVM compiler support for MIPS integrated assembler.
  • Improved Chromium PNaCl fast code generator, increasing code generation speed up to 50% compared to existing LLVM based code generator.
Technologies: TCP/IP, Ubuntu, Linux, Git, GCC, LIVE555, FFmpeg, Multithreading, Video Streaming, Audio Streaming, MIPS, LLVM, C++, C, HTTP Live Streaming (HLS), Android NDK, Google TV, Android TV, Android, GNU Debugger (GDB), Debugging, Embedded C, Embedded Systems

Software Engineer

2010 - 2011
Advanced Brain Monitoring
  • Developed software solutions for wireless EEG headsets.
  • Implemented a communication protocol library for data acquisition from all existing wireless devices.
  • Implemented desktop application for full EEG headset diagnostic and configuration, with signal graphing and accelerometer test and calibration.
  • Ported MATLAB code for detecting REM sleep phases and noise removal from EEG signals to C++ code.
  • Developed reader/writer library for industry-standard EDF format for storing EEG data, to increase interoperability with other EEG software solutions.
Technologies: Standard Template Library (STL), Multithreading, Object-oriented Programming (OOP), Object-oriented Design (OOD), RS-232, Windows, Visual Studio, Microsoft Foundation Class (MFC) Library, Microsoft Foundation Classes (MFC), C++, C, Bluetooth, Debugging, Firmware, Embedded Systems

Software Engineer

2004 - 2009
AP group
  • Developed multiuser client-server application for supply chain management and client invoicing.
  • Developed advanced data filtering and reporting capabilities, for creating more than 20 documents used in a process.
  • Developed an algorithm for estimating future sales, based on previous sales data and other input parameters.
  • Minimized returns of unsold goods bellow 10% allowed return limit.
  • Implemented application update system and database redundancy, allowing a system to run without major disruptions for more than 10 years.
Technologies: Reporting, Desktop App Design, Windows, Relational Database Design, Object-oriented Programming (OOP), Object-oriented Design (OOD), SQL DDL, SQL, Firebird, Delphi, C++, Debugging

Software Engineer, Freelance

2006 - 2008
ScalaP
  • Led a software development team of three engineers and two UX/sound designers building automated electronic roulette systems from the ground up.
  • Designed software, custom electronics, and communication protocols for three released products, deployed across five countries.
  • Prepared the systems for and passed EMC, LVD, and software certifications.
  • Designed the Solo R-750 single-player electronic roulette, which won the SUREXPO 2006 Technical Innovation Award in Warsaw, Poland.
Technologies: Relational Database Design, SQL DDL, SQL, Object-oriented Programming (OOP), Object-oriented Design (OOD), Windows, Firebird, Delphi, C++

Experience

The Peerplays Blockchain

https://github.com/peerplays-network/peerplays
Peerplays is the first decentralized global betting platform, disrupting the global gaming industry with a new paradigm of fairness, transparency, speed, and security. Peerplays removes the need for third-party betting operators, using Graphene technology and Delegated Proof of Stake (DPoS) to provide the fastest, most decentralized blockchain consensus model available today.

Smart Roulette

Bet Innovation's Smart Roulette is a fully automated electronic roulette, with up to eight-player seats. Each player seat features touch panel, bill and coin validators, ticket printer, iButton readers, self-sufficient security system for protecting game integrity and monitoring systems compatible with common gambling industry standards. Smart Roulettes are deployed in three countries so far, and its software is fully certified in accordance with local laws.

DeepToken Smart Contract

https://github.com/jitadigital/deeptoken
DeepToken is Ethereum based token, built for Mindark's flagship MMORPG game Entropia Universe, famous for largest existing virtual economy valued at $400 million USD. Token intended usage is for in-app purchases and future IP exchange.

FFmpeg for Android

FFmpeg for Android is a set of Android makefiles that enables configuration and building of the FFmpeg library within the Android source code tree using the Android NDK. The makefiles are designed to align with the workflow of system integrators working with Android source code.

Subzero - Fast Code Generator for PNaCl Bitcode

https://chromium.googlesource.com/native_client/pnacl-subzero/+/master
Subzero is a fast native code generator for PNaCl bitcode, intended as a lighter and faster replacement for existing LLVM based code generator.

MUP RS API for Delphi

https://github.com/obucinac/mup-rs-api-delphi
MUP RS API for Delphi is an Object Pascal port of API published by Ministry of interior affairs of the Republic of Serbia, for reading electronic personal identity cards and electronic vehicle registration certificates.

Education

2005 - 2010

Bachelor of Engineering Degree in Computer Engineering

Faculty of Computer Science, Union University - Belgrade, Serbia

Skills

Libraries/APIs

FFmpeg, SDL, wxWidgets, Standard Template Library (STL), Microsoft Foundation Class (MFC) Library, Microsoft Foundation Classes (MFC), POCO C++, PostgREST

Tools

GCC, Git, GitHub, OpenVPN, Visual Studio, GNU Debugger (GDB), CMake, GitLab, GitLab CI/CD, Graphene, Android NDK, Zephyr

Languages

C, C++, SQL, SQL DDL, Embedded C, Embedded C++, Delphi, Rust, MIPS, JavaScript, Bash Script, C#, XML, Solidity

Paradigms

Object-oriented Programming (OOP), Object-oriented Design (OOD), Cross-platform

Platforms

Linux, Android TV, Google TV, Ubuntu, Amazon EC2, Visual Studio Code (VS Code), Blockchain, Raspberry Pi, Windows, Android, Docker, Yandex Cloud, Heroku, Ethereum

Storage

PostgreSQL, Firebird, Database Modeling, Databases

Frameworks

Boost, LIVE555, Substrate, Parity Polkadot, Flutter

Other

HTTP Live Streaming (HLS), Relational Database Design, Debugging, Firmware, Bluetooth, Amazon Route 53, RS-232, Multithreading, Audio Streaming, Video Streaming, Data Engineering, Embarcadero RAD Studio, Embedded Systems, ESP32, ESP12, Bitcoin, LLVM, Desktop App Design, Reporting, TCP/IP, Non-blocking I/O, Boost.Asio, Gaming, Casino Games, Casinos & Gaming, LoRa, Airtable

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