☎️ Let's chat about your next project! 📆 Invite me & I'll send you my calendar link. 👋 I'm Sonja — a senior Webflow developer who builds websites and sales funnels that don't just look great — they convert. What I bring: ✅ 8+ years Webflow design & development ✅ Client First framework — clean, scalable, maintainable builds ✅ Figma → Webflow specialist (pixel-perfect, every time) ✅ 100+ websites & landing pages launched ✅ CMS architecture, interactions & animations ✅ SEO-optimized, mobile-first by default 💼 I work with SaaS startups, B2B companies, and professional service firms that need a senior-level build — not a template job. My most popular services: 🔹 Figma → Webflow Development 🔹 Full Website Design & Build 🔹 CMS Setup & Dynamic Content 🔹 Landing Pages & Marketing Sites 🔹 CRO & Conversion-Focused Design 🔹 Complex Sales Funnels & Integrations 🔹 UX Audits & Site Redesigns Integrations I work with: ⚙️ Salesforce · HubSpot · Zapier · Airtable · Make · and more ⚡ I move fast, communicate clearly, and deliver builds you can actually maintain and grow.

I'm a Full-stack Blockchain and Smart Contract Developer with 9+ years of experience building secure, scalable, and innovative Web3 products from DeFi platforms and DAOs to crypto exchanges and ZK integrations using Python and GoLang. I combine hands-on development with real-world insight as an active crypto trader on platforms like Binance and Poloniex, bringing a deep understanding of both blockchain technology and market dynamics. 🔐 Smart Contract Development & Auditing (EVM, Solana, ZK): ▪ EVM-compatible chains: Ethereum, Arbitrum, Optimism, Base, BNB Chain, Polygon ▪ Solana: Rust, Anchor, SPL tokens, Phantom wallet integration ▪ Token standards: ERC-20, ERC-721, ERC-1155, SPL ▪ Back-End Development: Node.js, Python, Nest.js, MySQL, RESTful APIs, GraphQL, and server-side integration ▪ Front-End Development: React.js, Next.js, Vue.js, Nuxt.js, HTML5, CSS3, and JavaScript (ES6+) Database Management: SQL, MySQL, PostgreSQL, MongoDB 🏗️ Blockchain Product Development: ▪ DApps for DeFi, NFTs, DAOs, DePIN, and enterprise use cases (logistics, healthcare, insurance, banking) ▪ Full-stack dApp development: Python, Golang, React.js, Next.js, Tailwind, TypeScript ▪ Web3 integrations: ethers.js, web3.js, viem, wagmi, RainbowKit ▪ Protocols & tools: IPFS, The Graph, Chainlink, Pyth 📈 Crypto Platforms & Trading Systems: ▪ Multi-currency wallets (hot/cold) using native nodes or APIs (Coinbase, Fireblocks, BlockCypher) ▪ Crypto exchanges with real-time trading, KYC/AML, order books, and secure Web3 integration ▪ Fiat-to-crypto gateways with Stripe, PayPal, and credit card support ▪ Swap services via DEX APIs (e.g., ShapeShift, Changelly) ▪ Market tracking platforms with live charts and portfolio tools ▪ Mobile crypto wallets: Flutter, React Native, Swift, Kotlin ▪ RESTful APIs & WebSocket services for external integrations ▪ Cross-platform desktop apps for Windows/macOS/Linux AI Automation Tool: Claude, Make, n8n 🧠 Leadership & Consulting: Sprint planning, technical documentation, and developer onboarding Code reviews, PR management, and mentoring junior engineers Tools: GitHub, JIRA, Trello, Slack, Notion Whether you're launching a new dApp, building a trading platform, or need a smart contract audit. I deliver clarity, security, and execution to turn ideas into reliable Web3 products.

Senior Blockchain Engineer with 8+ years of experience specializing in Blockchain, DeFi, Smart Contracts, NFTs, and Web3 technologies. Proven track record of designing and delivering secure, scalable, and high-performance decentralized applications and blockchain infrastructure. I design and build secure, scalable decentralized applications, smart contracts, DeFi protocols, NFT ecosystems, tokenization platforms, and blockchain infrastructure across EVM and non-EVM networks. My expertise spans the complete blockchain development lifecycle—from protocol architecture and smart contract development to auditing, backend services, deployment, and production support. Core Expertise: • Smart Contract Development (Solidity, Rust, Move) • DeFi Protocols (DEX, Staking, Yield Farming, Lending/Borrowing) • Token Development (ERC20, ERC721, ERC1155, ERC4626) • NFT Marketplaces and Launchpads • Layer 2 Solutions and Cross-Chain Integrations • Web3 Backend Development (Golang, Node.js, Python) • Smart Contract Auditing and Security Best Practices • Account Abstraction (ERC-4337) • DePIN and Real World Asset (RWA) Tokenization • AI-Powered Blockchain Applications • Agentic AI for On-Chain Automation • MCP and AI Agent Integrations for Web3 Blockchain Ecosystems: Ethereum, Base, Arbitrum, Optimism, Polygon, BNB Chain, Avalanche, Solana, Sui, Aptos Technology Stack: Solidity, Rust, Golang, TypeScript, Node.js, Python, Foundry, Hardhat, OpenZeppelin, Ethers.js, Web3.js, The Graph, Docker, Kubernetes, AWS I focus on building production-grade blockchain solutions with security, scalability, and long-term maintainability in mind. Whether you need a DeFi protocol, NFT platform, token ecosystem, Web3 backend, smart contract audit, or AI-powered blockchain solution, I can help bring your vision to production. Keywords :- Blockchain, Web3, Ethereum, Solidity, EVM, Smart Contracts, ERC-20, ERC-721, ERC-1155, DeFi, DAO, DApp, NFT, Layer 2, Rollups, Optimistic Rollups, ZK-Rollups, Polygon, Arbitrum, Optimism, Base, Avalanche, BNB Chain, Hyperledger, Cosmos, Polkadot, Substrate, Solana, Rust, Go, Golang, Node.js, TypeScript, JavaScript, React, Next.js, Express.js, NestJS, Python, Django, FastAPI, GraphQL, REST API, WebSockets, gRPC, PostgreSQL, MySQL, MongoDB, Redis, Firebase, IPFS, Filecoin, Arweave, Chainlink, The Graph, Hardhat, Foundry, Truffle, Ganache, Remix IDE, Ethers.js, Web3.js, Viem, Wagmi, OpenZeppelin, MetaMask, WalletConnect, Multisig, Gnosis Safe, Account Abstraction, ERC-4337, MPC Wallet, Cryptography, SHA-256, SHA-3, Keccak-256, ECDSA, EdDSA, BLS Signatures, Zero-Knowledge Proofs, zkSNARKs, zkSTARKs, Merkle Tree, Merkle Proof, Consensus, Proof of Work, Proof of Stake, Delegated Proof of Stake, PBFT, Tendermint, Cosmos SDK, Chaincode, Oracle, Tokenomics, Staking, Yield Farming, Liquidity Pool, AMM, Uniswap, PancakeSwap, SushiSwap, Cross-Chain Bridge, Cross-Chain Messaging, MEV, Flash Loans, Gas Optimization, Smart Contract Auditing, Slither, Mythril, Echidna, Fuzz Testing, Unit Testing, CI/CD, Docker, Kubernetes, AWS, Azure, Google Cloud, Git, GitHub Actions, Jenkins, Terraform, Linux, Nginx, Apache Kafka, RabbitMQ, Microservices, Event-Driven Architecture, OAuth 2.0, JWT, OpenAI API, Anthropic Claude API, LangChain, LangGraph, CrewAI, AutoGen, MCP, AI Agents, AI Automation, RAG, Vector Database, Pinecone, Weaviate, Milvus, ChromaDB, Prompt Engineering, LLMOps, Workflow Automation, n8n, Make, Zapier, GoHighLevel, Selenium, Playwright, Puppeteer, TensorFlow, PyTorch, Hugging Face, Computer Vision, NLP, MLOps, DevOps, Backend Development, Full-Stack Development, API Integration, Webhooks, Serverless, Edge Computing

Need an AI agent, voice bot, or SaaS product that actually ships to production—not another demo that dies after the pitch? That's where I help. I recently built an AI voice receptionist (live at callersync..com) that answers calls in real time, books appointments, and logs every conversation automatically. I've also helped clients reduce manual workloads by 60% through automation and built backend systems handling 100,000+ API requests per day. ⭐ What clients say: • "Expert in Next.js & React.js — dedicated resource." • "Quick turnaround, very talented." • "Takes ownership and enhances performance." 💼 What I build: • AI Voice Agents & Chatbots — OpenAI Realtime, Claude, Whisper, Deepgram, ElevenLabs, Twilio • AI Automation & Workflows — LangChain, n8n, RAG systems, document intelligence • Full-Stack SaaS Applications — Next.js, React, Node.js, TypeScript, PostgreSQL • APIs & Integrations — Stripe, OAuth, Webhooks, CRMs, scheduling platforms • Scalable Cloud Infrastructure — AWS, Cloudflare, Docker, Vercel, CI/CD ⚙️ Tech Stack: React • Next.js • TypeScript • Node.js • NestJS • Python • PostgreSQL • MongoDB • Redis • OpenAI • Claude • LangChain • AWS • Docker • CI/CD ✔ Why clients hire me: • 25+ successful projects delivered • 93% Job Success Score • Fast communication and clear updates • Production-focused development, not prototypes • Proactive suggestions that improve the product and reduce long-term costs Whether you have an AI idea, a half-built application, or a manual process that's slowing your team down, send me a message. I'll walk you through exactly how I'd build it, what challenges to expect, and the fastest path to production.

Hello and thank you for visiting my profile! I’m Oleksii - a Senior Full-Stack Engineer with 5+ years of experience building production-ready, scalable web applications end to end using React, Next.js, Node.js, TypeScript, databases, and AI. I help startups and growing companies move from ideas or unstable systems to reliable, high-performance products with clean architecture, real backend logic, and thoughtful UX. What I usually help with • Building and maintaining full-stack applications (frontend, backend, APIs, data) • Designing clean application architecture and reusable components • Developing backend logic, API layers, and integrations • Improving performance and stability across the stack • Running A/B tests and product experiments based on real data • Integrating AI features (chat flows, smart suggestions, automation) • Building design-system-friendly UIs that scale with the product • Setting up CMS-driven content and data models without slowing the team A bit about where I’ve worked • Grammarly - worked on product UI components, performance refactoring, experiments, and CMS migrations in a large-scale production environment • Iceberg io - built AI-powered messaging features with OpenAI, rebuilt the landing experience, and implemented analytics and experimentation • ChainLink Education - developed a full SaaS platform end to end, including frontend, backend logic, data flow, and CMS-driven architecture Industries I’ve Delivered Solutions For: Fintech & Crypto: secure, high-performance full-stack development and database management Health & Wellness: mobile app developer for patient monitoring and wellness platforms Logistics & Supply Chain: automation, workflow, API integrations, real-time dashboard Education & E-Learning: interactive platforms with responsive web design and Nextjs Social Media & Marketing: scalable full stack software developer solutions with React.js front end My Approach to Projects: I focus on understanding business goals first, translating them into robust full stack web developer solutions with React.js, Node.js, and PostgreSQL / MongoDB databases. Every project is structured for performance, maintainability, and future scalability. I prioritize automation, clean code, and efficient workflow to save time and reduce risk for clients. Long-Term & Scalable Solutions: Many clients hire me as a full stack software engineer or software project manager for long-term collaboration. I provide guidance on architecture, Next.js frontends, React Node integrations, and mobile app development strategy. I also implement AI agents or OpenAI solutions when needed to enhance platform capabilities. Hands-On Technical Leadership: As a senior full stack developer react node and React full stack developer, I lead teams, review code, and ensure full stack development projects meet the highest standards. I integrate API, manage database structures, and maintain GitHub repositories for seamless collaboration. Why clients choose me: I combine React developer skills, Node.js backend expertise, and full full stack development knowledge to deliver results aligned with timelines and budgets. I provide long-term experience, from project planning to deployment, ensuring every workflow, database, and dashboard is optimized for performance. I’m comfortable owning features from idea to production, working closely with product, design, and backend teams, and making pragmatic technical decisions that move the product forward. Feel free to share the details of your project - I’ll review them and suggest the best way to achieve your goals efficiently.

I build and secure smart contracts that move real money, and I don't stop until they're production-ready. Over the past 4+ years I've written, tested, and audited Solidity code for live Web3 products, currently serving as Blockchain Lead at a Web3 domain platform, where I designed and shipped multi-chain smart contracts that let users purchase domains seamlessly across different blockchain networks. Before that, I built and tested smart contracts for NFT game platforms at Ibriz. What I bring to your project: Smart contract development — Solidity, Foundry, EVM chains, Base Security auditing — static analysis (Slither), test coverage, stack-optimization, vulnerability mitigation before mainnet deploy Cross-chain infrastructure — CCIP and LayerZero v2 messaging, multi-chain architecture Account abstraction — ERC-4337, smart accounts, gasless/sponsored transactions Full delivery, not just code — as a Blockchain Lead I also run scoping, testing pipelines, and cross-functional delivery with frontend/backend teams, so you get someone who can own a feature end-to-end, not just take a ticket I care about getting the details right: proper test coverage, gas-optimized code, and contracts that pass audit scrutiny, because in Web3, a bug isn't a bug ticket, it's a headline. If you need smart contracts that are secure, efficient, and actually ship, let's talk about what you're building.

Web3 Growth & Social Media Marketing (CMO-Level) | GTM, BD Partnerships, Fundraising & TGE/ICO Expert | Helped Raise $50M+ | Fully Verifiable I have extensive experience in leading Cryptocurrency and AI startups, with a proven record of scaling them from zero to millions of users, building thriving communities, supporting fundraising efforts, and guiding projects through successful public launches. Also specialized in growth, social media marketing, go-to-market strategy, community building, business development, and TGE/ICO launch execution. I have led successful fundraising rounds for projects backed by top-tier VCs such as Binance Labs and IDG, managed multi-exchange listings, and contributed to projects achieving hundreds of millions in market cap at launch. I also lead and manage my own 100K+ Web3 community across social platforms and am a Top Rated Plus freelancer on Upwork, reflecting consistent delivery and long-term client trust. As an active crypto investor and collaborator with leading venture capital firms, I bring deep, practical insights into startup scaling, ecosystem growth, and the broader crypto investment landscape. 🌍 Industries Grown Crypto, RWAs, AI, AI Agents, DeFi, Blockchain Infrastructure, CEX/DEX, EVM Wallets, Telegram Apps, Memecoins, Game-Fi, and more. 💼 Some of My Clients Bittensor (xTAO), Grindery AI, Ryze Labs, Mysten Labs, Gate, LayerZero, One Click Labs, Enso, LiFi, Gnosis Safe, Charged Ventures, Magic Craft, Alethea AI, Sensay, and others. ⚡ Core Skills & Expertise ✅ Web3 & Crypto Social Media Growth Strategy and Execution ✅ Venture Capital Support, Partner Introductions & Fundraising Strategy ✅ Go-to-Market (GTM) & Token Launch Execution ✅ Community Building, Engagement & Scaling ✅ KOL & Influencer Marketing Campaigns ✅ Viral & Content Strategy for Twitter (X) & Telegram ✅ ICO / IDO / TGE Launch Planning & Exchange Listings ✅ Ambassador, Affiliate, Airdrop & Galxe Campaigns ✅ PR & Press Strategy for Third-Party Validation ✅ Whitepapers, Tokenomics & Fundraising Collateral ✅ Business Development & Ecosystem Partnerships ✅ Performance Marketing (PPC, Meta, X Ads) 📈 Recent Case Studies xTAO (Bittensor Ecosystem) → Led marketing and strategic fundraising initiatives for the largest TAO holding company. → $30M raised from DCG, Animoca, Bittensor → 5M+ impressions across social and PR Grindery AI (Binance Labs S4) → Scaled to 4M users in 9 months, grew a 1M+ community, supported $5M fundraising, and launched TGE at a $50M market cap. EcoYield → Directed growth, strategy, fundraising, and global RWA expansion across Europe. → Tokenized $3M+ in solar and AI compute assets → Built investor materials (roadmap, whitepaper, tokenomics) → Engaged 70+ VCs 🧠 Work Philosophy I’ve worked directly with founders, VPs, and C-level teams across leading Web3 and AI startups worldwide, applying data-driven decision-making and execution-first frameworks. Ideas are cheap. Execution is everything. That’s what I deliver. I also offer complimentary strategic support depending on project type and budget. Looking for a hands-on operator who goes beyond what’s required to exceed project goals? Let’s connect and discuss your project today. 🔍 SEO Keywords Web3 marketing, crypto growth, AI marketing, blockchain promotion, TGE strategy, VC fundraising, community management, influencer marketing, Telegram growth, DeFi marketing, crypto PR, content strategy, NFT branding, token launch, performance analytics, social media growth, venture partnerships, GTM execution, startup scaling. IDO, ICO, Pre-sale.

Hi, I’m Muhammad Mustafa Tahir, a Full Stack Developer with 4+ years of experience building modern web applications and blockchain solutions. With a strong Computer Science background and hands-on experience across 25+ successful projects, I specialize in developing scalable, secure, and high-performance applications using the MERN stack and Web3 technologies. From full-stack web platforms to smart contracts and decentralized applications, I focus on delivering clean, maintainable, and reliable solutions that help businesses grow. ### What I Can Build for You: ✅ Full Stack MERN Applications (MongoDB, Express.js, React.js, Node.js) ✅ React.js & Next.js Frontend Development ✅ REST APIs & Backend Development ✅ Authentication & Authorization Systems (JWT, OAuth, Firebase) ✅ Database Design & Optimization (MongoDB, PostgreSQL) ✅ Smart Contract Development (Solidity) ✅ DeFi Platforms: Staking, Yield Farming, Lending & Borrowing Protocols ✅ Token Launch Platforms: ICO, IDO & Token Vesting Systems ✅ NFT Marketplaces & Web3 DApps ✅ Wallet Integration: MetaMask, WalletConnect & Other Web3 Wallets ✅ Cross-Chain Bridges & Multi-Chain Token Solutions ✅ Web3 APIs & Backend Integration ✅ Blockchain Data Indexing & Analytics (The Graph, Chainlink Oracles) ✅ Decentralized Storage Integration (IPFS, Pinata, Arweave) ✅ Smart Contract Auditing, Bug Fixing & Performance Optimization I take on projects only when I’m confident I can deliver exceptional results. Whether you need a modern full-stack web application, a blockchain solution, or a combination of both, I am committed to delivering secure, scalable, and high-quality products. Let’s discuss how I can help bring your idea to life. Best regards,

Need a secure Solidity contract, DeFi module, or crypto payment backend for real transactions? I build production-ready Web3 systems with safe wallet flows and reliable APIs. Most Web3 problems do not come from code that simply fails to compile. They come from weak transaction handling, unsafe smart contract logic, poor wallet-state validation, broken backend sync, missing tests, and rushed deployment. That is where I help. I work with founders, CTOs, startups, and product teams building Web3, DeFi, fintech, crypto payment, and backend-heavy products. My focus is secure architecture, clean implementation, and production reliability. What I can build for you: • Solidity smart contracts for ERC-20, ERC-721, ERC-1155, staking, vesting, escrow, token launches, bonding curves, and DeFi logic • Web3 backends using Node.js, NestJS, TypeScript, PostgreSQL, Redis, Docker, AWS, Nginx, and CI/CD • Crypto payment systems with USDT escrow flows, wallet dashboards, deposits, withdrawals, transaction tracking, and admin controls • DeFi platforms with token swaps, fair-launch flows, bonding curves, liquidity automation, and real-time pricing • dApp integrations with React, Next.js, MetaMask, Ethers.js, Web3.js, Wagmi, RainbowKit, and smart contract event handling • Production support including smart contract review, gas optimization, API cleanup, backend hardening, deployment, monitoring, and documentation Proof: • 100% Job Success on Upwork • Rising Talent status • $10K+ Upwork earnings • 414+ Upwork hours • CEH-certified security background • Built Web3 systems across USDT escrow, ERC-20 swaps, fair-launch token platforms, NFT marketplaces, SaaS backends, wallet flows, and transaction-heavy APIs Client feedback: “Delivered production-ready code with no hand-holding.” “Technically strong in blockchain concepts and proactive in solving issues.” “Delivered clean, well-structured code on time.” Core stack: Solidity, Ethereum, Polygon, Arbitrum, Base, Hardhat, Foundry, OpenZeppelin, Ethers.js, Web3.js, Wagmi, MetaMask, IPFS, Chainlink, Node.js, NestJS, TypeScript, PostgreSQL, Redis, Docker, AWS, Nginx, CI/CD, React, Next.js. Send me what you are building, what is already done, and where the risk is. I will help you define the safest technical path and build a stable Web3 system around it.

Most smart contract engineers can write code. Fewer can break it — and even fewer understand both sides well enough to build secure systems from scratch. I've completed 50+ security reviews on CodeHawks and Sherlock across DeFi and NFT protocols, covering reentrancy, oracle manipulation, access control bypasses, and MEV attack vectors. I also built Zawyafi — a full-stack RWA tokenization platform — solo, from seven EVM contracts to Chainlink CRE workflows connecting live POS data to on-chain USDC payouts. That combination is rare: I can audit your existing contracts and build new ones securely. What I do for clients: Development: - Smart contract development (Solidity, Foundry) - RWA tokenization architecture - DeFi protocol implementation (lending, DEX, vaults) - Full-stack dApp (contracts + Next.js frontend) Security: - Smart contract security audits - Pre-audit codebase preparation - Remediation roadmaps with business impact context Security consulting (no code required): Not sure what kind of audit you need, or which firm to hire? I help protocols: - Choose between solo auditors vs. firms - Identify auditors specialized in their stack (lending, bridges, ZK, NFTs) - Prepare their codebase to get more value from an audit - Understand realistic price ranges and timelines I'm available for: One-time audits, ongoing security retainers, smart contract development projects, and short consulting calls.