Open for projectsLooking for full-time/part-time

Full-stack developer

Yurii Yakymenko — from landing pages to production apps, full-stack development for any project size

I run the whole project: frontend, backend, deployment, automation, smart contracts, AI integration. Experience in Web3 protocols, real-time services and spec-driven development.

About

00 / About

Full-Stack Developer with 4 years of experience building production web apps with React/Next.js, Node.js, and TypeScript. Also work as a Web3 developer writing Solidity smart contracts, and as an AI integration engineer connecting LLM features into products. Additionally proficient in Python, C#, and Rust. Experienced both shipping projects independently end-to-end and collaborating within small teams alongside senior engineers on zero-knowledge identity systems and decentralised applications.

Tech stack

01 / Stack

Primary

ReactNext.jsTypeScriptNode.jsTailwind CSSPostgreSQLPrismaReduxZustandREST APIRust

Blockchain & Web3

SoliditySmart ContractsHardhatethers.jsNFT

AI & Integrations

LLM IntegrationGroqOpenAIClaudeClaude DesignRAG PipelinesPrompt Engineering

Infrastructure & Tools

DockerCI/CDNginxLinuxGitFigma-to-Code

Auth & Real-time

OAuth2NextAuth.jsStream Video SDKWebRTCWebSocketsDiscord API

Process

AgileScrumJiraTrelloMiroSpec-Driven DevGithub Speckit

Services

02 / Services
01

Landing pages — building landing pages for a product or campaign, plus custom CRM systems — client and deal management, sales pipelines, internal admin tools.

02

Process automation & chat bots — scripts and integrations that take routine work off the team, Telegram and Discord bots — from simple notifications to bots with business logic.

03

Frontend & Backend development — React/Next.js interfaces built to spec, the APIs, databases, and auth behind them, deployed with Docker, CI/CD, Nginx, SSL — from commit to production.

04

AI integrations — AI integration engineering — LLM, RAG, orchestration, prompt engineering for product scenarios.

05

Smart contracts / Web3 — Solidity smart contracts, EVM protocols — writing, auditing logic & test coverage.

Work Experience

03 / Work Experience

Centrifuge.digital

January – March 2025
React · Next.js · TypeScript · Discord API · CI/CD

Part of the POSTHUMAN ecosystem (same team as metarchy.space) — a quest platform rewarding POSTHUMAN tokens exchangeable for Cosmos-chain crypto.

  • Built a Discord-based authentication flow using bots and webhooks to verify and link user identities
  • Paired with a peer frontend developer and assisted with the CI/CD pipeline and server deployment (Nginx, Linux, SSL)
centrifuge.digital →

Metarchy.space

December 2023 – March 2025
React · Next.js · TypeScript · Redux · Docker · Figma · CI/CD

Blockchain NFT strategy game — a 3-person team building an on-chain strategy game with NFT-based Actors on a hexagonal board.

  • Implemented responsive UI from Figma designs and built core game-mechanic logic (hex-board interaction, NFT Actors) using Redux
  • Integrated the Keplr wallet API despite limited documentation through independent research and testing
  • Paired closely with a peer frontend developer, cutting typical task turnaround from about a week to three days; assisted with CI/CD and server deployment (Nginx, Linux, SSL)
metarchy.space →

ZK Identity & Authentication

March – October 2023
Solidity · Mina Protocol · TypeScript · SvelteKit · Hardhat · ethers.js · Google OAuth

Grant-funded MVP built alongside a senior developer (circuits/ZK logic), bridging Web2 auth with on-chain ZK identity.

  • Developed Solidity smart contracts (ERC20 + user registry) integrating a zk-SNARK verifier to gate token transfers behind zero-knowledge proofs; also built Mina Protocol smart contracts for a parallel MVP
  • Resolved the Google OAuth ↔ ZK-circuit integration challenge by using the Google auth token itself as a cryptographic key
  • Built the SvelteKit frontend and Google OAuth 2.0 flow; wrote test suites (Hardhat, ethers.js, Mocha/Chai) covering contracts, auth, and circuit integration paths
  • Researched zk-proof (zk-SNARK) technology and Mina Protocol to implement the zk circuits and a parallel MVP on Mina
zk-auth.com →

My Personal Projects

04 / My Personal Projects

Study English App

December 2025 – June 2026
Next.js 14 · TypeScript · PostgreSQL · Prisma · NextAuth.js · Groq SDK · Stream Video SDK · Zustand · Docker

An app for learning English with video lessons and AI tools.

  • Researched video infrastructure options and selected Stream Video SDK (GetStream.io) over a custom WebRTC build, reducing dev time while solving live transcription during calls
  • Built AI-generated flashcards from conversation transcripts using Groq SDK; implemented Google OAuth via NextAuth.js v5 with role-based access (Teacher/Student)
  • Containerised the application with Docker; managed state with Zustand and secured the app via custom proxy middleware
study-english-app-teal.vercel.app →

Contact

05 / Contact

Open to project work and full-time roles. Describe the project, stack and timeline.