alko89

Senior Backend & Blockchain Engineer

Experienced Senior Backend Developer with a strong background in building scalable, high-performance backend systems for blockchain, API integrations, and Web3 platforms. I have worked on diverse projects, including developing core admin platforms, subscription management services, and implementing blockchain solutions like NFT frameworks. Specializing in TypeScript, Node.js, blockchain technologies, and API architecture, I have contributed to key infrastructures such as Moralis, Authtrail, and 0xcert, delivering reliable solutions for API usage management, account abstraction, and enhanced data integrity. I thrive in environments where backend efficiency, system architecture, and blockchain innovation intersect. My passion lies in designing systems that empower users and businesses while driving forward the Web3 ecosystem.


Experience: 5 years

Yearly salary: $80,000

Hourly rate: $40

Nationality: 🇭🇷 Croatia

Residency: 🇭🇷 Croatia


Experience

Contract Senior Backend Developer
Moralis Web3
2021 - 2024
Designed and implemented a billing coordinator service for the entire Moralis infrastructure, managing paid subscriptions and processing users' API usage. Developed and maintained internal validation services to ensure data integrity and system reliability. Integrated Thirdweb's account abstraction contract factory to enable seamless trading accounts within Moralis Money. Designed an efficient usage service dashboard, providing real-time insights and enhancing platform performance monitoring. Spearheading the development of the ads service for enhanced token info and token ads, allowing projects to showcase their token or purchase ad space on Moralis Money. Working on token metadata solutions to enhance token discovery and improve data accessibility. Utilized TypeScript and Node.js to build scalable and reliable backend solutions.
Contract Forum Specialist – Bitcoin, Lightning Network, C++
MoralisAcademy
2020 - 2025
Provided expert-level answers and support on community forums related to Bitcoin, the Lightning Network, and C++. Engaged with users to clarify technical concepts, troubleshoot issues, and offer insights into blockchain and programming challenges. Fostered a collaborative environment by guiding discussions and sharing knowledge on cutting-edge cryptocurrency and C++ developments.
Backend Developer – VoIP Client (Doubango Framework)
Kalmia LTD
2019 - 2020
Developed and maintained backend systems for a VoIP client using the Doubango framework, written in C, for both mobile and desktop platforms. Supported real-time communication features, ensuring reliable and efficient performance across devices. Troubleshot and optimized VoIP client functionalities to improve call quality and user experience.
Backend Developer – Authtrail (Blockchain Integration)
Authtrail
2019 - 2020
Developed core features and APIs for Authtrail, enabling the anchoring of traditional database fingerprints on the blockchain using TypeScript and Node.js. Ensured secure, scalable, and efficient blockchain integrations to enhance data integrity and traceability. Collaborated with blockchain and database teams to streamline processes and optimize API performance.
Developer – 0xcert Framework (NFTs)
0xcert
2019 - 2019
Maintained and enhanced the 0xcert framework, focusing on NFT integration and API development using TypeScript and Node.js. Implemented new features and optimized existing APIs to improve performance and scalability in blockchain applications. Collaborated with cross-functional teams to ensure smooth integration of NFT functionality with various platforms.
Embedded Developer – Network Drivers (Broadcom)
Borea d.o.o.
2014 - 2015
Developed and maintained network drivers for the Broadcom Linux distribution, optimizing performance for ISP modem hardware. Collaborated with ISP clients to ensure reliable network connectivity and seamless integration with their infrastructure. Troubleshot and resolved low-level networking issues, improving modem performance and reducing downtime.
Embedded Developer – DataBox System
Solvera Lynx
2013 - 2014
Developed and maintained the DataBox embedded system, leveraging PTXdist for build configuration and using C++/Qt for userspace software development. Provided technical support and updates for legacy DataBox systems, utilizing Tiger-BASIC. Collaborated on system optimization, ensuring robust performance and stability for embedded solutions.

Skills

aws
linux
nestjs
typescript
node
english