Hire the Best Blockchain Developers
in Spain
Salamanca, Spain
I'm a freelance Blockchain specialist with over 9 years of experience delivering high-quality decentralized applications, smart contract systems, and Web3 infrastructure. I've worked with a wide variety of clients. From DAOs and startups to established tech companies building: ๐ง Smart contracts (Solana, Solidity, Hardhat,...) ๐งฎ DeFi platforms (staking, liquidity mining, fee management, Native DEX,...) ๐ผ๏ธ NFT marketplaces (minting, royalties, IPFS/Pinata, metadata management) ๐ Cross-chain tools and integrations (Safe, Aave, Uniswap, Metamask, THORChain, CosmosSDK, IOTA,...) ๐งฐ Custom tooling and dApp frontends (React, Node.js, TypeScript, Ethers.js, Wagmi, Go,...) I'm also experienced in project leadership and backend systems, which helps me collaborate with full-stack teams, manage timelines, and deliver reliable software even under tight deadlines. โ Strong communication โ Web3-native mindset โ Adaptable to remote teams and async workflows If youโre looking for a committed and hands-on blockchain expert to bring your Web3 product to life, or scale it. Letโs connect.
- Blockchain
- Blockchain Architecture
- Blockchain Development
- Ethereum
- JavaScript
- Python
- C#
- Solidity
- Docker
- Cryptocurrency
- Engineering Tutoring
- C
- Smart Contract Development
- Web3
Barcelona, Spain
โ๏ธ๐๐ฒ๐ ๐ฎ ๐๐ฅ๐๐ ๐๐-๐บ๐ถ๐ป๐๐๐ฒ ๐๐น๐ผ๐ฐ๐ธ๐ฐ๐ต๐ฎ๐ถ๐ป ๐๐ผ๐ป๐๐๐น๐๐ฎ๐๐ถ๐ผ๐ปโ๏ธ Iโm a senior blockchain engineer focused on building and scaling production-grade Web3 systems, from smart contracts to full DeFi architectures and backend integrations. I collaborate with security auditors (including Certik) on selected projects when formal audit stage is required, but my main focus is clean architecture, secure contract design, and long-term maintainability before audit even becomes necessary. ๐ Blockchain Expertise 11+ years building Web3 infrastructure, including: Smart contract development (Solidity, Rust, Move) Tokenomics & stablecoin architecture DeFi protocols: staking, liquidity pools, AMMs, lending/borrowing Wallet & blockchain integration Cross-chain bridges & interoperability Security audits, gas optimization, and threat analysis Node setup, backend APIs, indexing & on-chain data pipelines ๐๐ถ๐ด๐ต๐น๐ถ๐ด๐ต๐๐ฒ๐ฑ ๐ฃ๐ฟ๐ผ๐ท๐ฒ๐ฐ๐๐: Gold-backed Stablecoin System (Liechtenstein Launch) โ KYC onboarding, Sumsub integration โ Smart contracts on Ethereum + Polygon โ Oracle pricing + OTC gold price feeds โ Token mint/burn mechanics โ Reserve-backed auditing model โ Whitelist & transfer-restriction compliance โ Storage-fee mechanism (token balance decay) โ Full on-chain/off-chain architecture DeFi Protocols (AMMs, staking, farming) โ Smart-contract suite (Solidity) โ Reward distribution mechanisms โ Price oracle integration (Chainlink) โ Security hardening & audit fixes NFT platforms & minting engines โ ERC-721 / 1155 collections โ Royalty logic, metadata generation โ Claiming contracts, allowlists, randomness ๐๐น๐ผ๐ฐ๐ธ๐ฐ๐ต๐ฎ๐ถ๐ป ๐ง๐ฒ๐ฐ๐ต ๐ฆ๐๐ฎ๐ฐ๐ธ: Smart Contracts: Solidity, Rust (Solana), Move (Aptos/Sui) Frameworks: Hardhat, Foundry, Truffle, Anchor Security: Slither, Mythril, Echidna, Certora On-Chain Data: TheGraph, SubQuery, custom indexers Blockchains: Ethereum, Polygon, BNB Chain, Arbitrum, Optimism, Avalanche, Solana, TON Backend: Node.js, NestJS, PostgreSQL, Redis, Docker Tools: Chainlink, Safe (Gnosis), IPFS, Pinata, Fireblocks Want a secure, scalable blockchain product, not a risky MVP? Send the documentation, and letโs build it correctly from day one. ๐๐ฒ๐๐๐ผ๐ฟ๐ฑ๐: Blockchain, Web3, Blockchain Developer, Web3 Developer, Smart Contract Developer, Solidity Developer, Rust Developer, Move Developer, Ethereum Developer, DeFi Developer, Smart Contract Audit, Security Audit, Tokenomics, Stablecoin Development, NFT Development, ERC20, ERC721, ERC1155, Solidity Engineer, Blockchain Architecture, DApp Backend, Oracle Integration, Chainlink, Hardhat, Foundry, Web3 Security, Multi-Chain Deployment, DeFi Protocol, Yield Farming, Staking Contract, Vesting Contract, Governance Token, On-Chain Data, TheGraph, EVM Developer, Crypto Developer, Blockchain Consultant, Token Development, ICO/IDO Smart Contracts, Bridge Development, Layer 2 Developer, Polygon, Arbitrum, Optimism.
- Blockchain
- Blockchain Architecture
- Blockchain Development
- Ethereum
- Smart Contract
- JavaScript
- Solana
- Python
- web3.js
- Rust
- Solidity
- Node.js
- Cryptocurrency
- React
- HTML
Barcelona, Spain
Iโm a senior Shopify App Developer, MERN specialist, and full-stack developer with 10+ years of experience in Shopify, Shopify Plus, custom apps, public apps, private apps, API integrations, data migration, and complex eCommerce systems. As a Shopify App Developer, full-stack developer, web developer, react developer, python developer, wordpress developer, and blockchain developer, I build stores, apps, dashboards, and workflows that are fast, stable, scalable. ๐ Full-Cycle Shopify, MERN, and App Development. As a Shopify App Developer and full-stack developer, I donโt just write code. I build eCommerce systems that support real business operations. Whether you need a Shopify app, Shopify Plus customization, Shopify data migration, admin tools, public app development, private app development, shopify speed improvement, dropshipping setup, automation, or technical support, I can help from planning to launch. My main focus is Shopify App Developer work, MERN development, full-stack developer solutions, and scalable systems for brands that need clean code, better UX, backend logic, and conversion. I also support web developer tasks, react developer work, python developer scripts, wordpress developer projects, blockchain developer features, mern stack apps, React interfaces, Node.js backends, MongoDB databases, and API integrations. ๐ป Core Expertise - Shopify App Developer services for custom Shopify apps, public apps, private apps, and embedded apps - Shopify App Developer support for Shopify Plus workflows, checkout logic, admin tools, subscriptions, and B2B features - Shopify App Developer integrations with APIs, ERPs, CRMs, payments, fulfillment tools, and analytics platforms - MERN and mern stack development using MongoDB, Express.js, React, and Node.js - full-stack developer support for frontend, backend, databases, cloud services, and deployment - full stack developer architecture for dashboards, portals, SaaS tools, and internal systems - react developer work for storefronts, app interfaces, Polaris components, and interactive UI - React development with Redux, TypeScript, JavaScript, HTML, CSS, SCSS, and component logic - python developer support for data migration, scripts, automation, backend tools, and API workflows - wordpress developer support for WooCommerce, WordPress migration, plugin logic, and frontend fixes - web developer support using HTML, CSS, JavaScript, Liquid, PHP, Laravel, APIs, and cloud tools - blockchain developer support for wallet flows, Web3 integrations, NFT logic, and token-gated features โญ How I Can Help If you need a Shopify App Developer to build a custom app, I can plan the logic, design the architecture, develop the interface, connect APIs, test the workflow, and prepare the app for real use. If you need a MERN developer or mern stack expert, I can build web apps with React, Node.js, Express, and MongoDB. If you need a full-stack developer or full stack developer for an eCommerce platform, I can connect frontend, backend, database, and integrations into one stable system. I can also help as a react developer for clean interfaces, as a python developer for scripts and automation, as a wordpress developer for migration and WooCommerce support, as a web developer for theme and frontend work, and as a blockchain developer for Web3 features. My Shopify App Developer experience also covers app migration, debugging, webhooks, billing logic, product sync, order sync, customer sync, inventory sync, and dashboards. ๐ฏ My Approach Every project starts with understanding your store, business model, app logic, customer journey, data structure, and technical constraints. As a Shopify App Developer, MERN engineer, full-stack developer, full stack developer, react developer, python developer, wordpress developer, web developer, and blockchain developer, I focus on stable architecture, clean development, QA, and simple handoff. For Shopify projects, I check app logic, Shopify API limits, webhook flows, data migration risks, checkout behavior, speed issues, and conversion gaps. For MERN and mern stack projects, I focus on React structure, Node.js backend logic, MongoDB data design, API security, deployment, and scalability. For full-stack developer and full stack developer tasks, I make sure frontend, backend, database, and integrations work together without fragile shortcuts. Clients choose me because I combine Shopify App Developer experience, MERN execution, full-stack developer thinking, full stack developer flexibility, and real eCommerce understanding. If you need a reliable Shopify App Developer, MERN specialist, full-stack developer, full stack developer, mern stack engineer, react developer, React expert, python developer, wordpress developer, web developer, blockchain developer, Shopify data migration specialist, custom app builder, API integration expert, or eCommerce technical partner, lets discuss asap.
- Shopify
- Node.js
- JavaScript
- CSS
- HTML
- MongoDB
- WordPress
- React Native
- CSS 3
- Software Debugging
- App Development
- Python
- Figma
- Laravel
- API Integration
- React
- TypeScript
- MERN Stack
- Ecommerce
- Shopify Plus
Altea, Spain
Experienced blockchain developer with strong background in smart contract development, blockchain architecture and backend. Proven ability to implement and test decentralized applications on Ethereum and Hyperledger platforms.
- Blockchain
- Ethereum
- Hyperledger Fabric
- Golang
- Node.js
- JavaScript
- Git
- Docker
Barcelona, Spain
๐ ๐ต๐ฒ๐น๐ฝ ๐ฐ๐ผ๐บ๐ฝ๐ฎ๐ป๐ถ๐ฒ๐ & ๐ฒ๐ป๐๐ฟ๐ฒ๐ฝ๐ฟ๐ฒ๐ป๐ฒ๐๐ฟ๐ ๐ฏ๐๐ถ๐น๐ฑ ๐๐ต๐ฒ ๐ฏ๐ฒ๐๐ ๐ช๐ฒ๐ฏ๐ฏ ๐ฝ๐ฟ๐ผ๐ท๐ฒ๐ฐ๐๐ ๐ฎ๐ป๐ฑ ๐๐น๐ผ๐ฐ๐ธ๐ฐ๐ต๐ฎ๐ถ๐ป ๐ฏ๐ฟ๐ฎ๐ป๐ฑ๐ ๐ ๐๐ต๐ฟ๐ผ๐๐ด๐ต ๐ฆ๐๐๐๐๐๐๐ ๐ฑ๐ฒ๐๐ฒ๐น๐ผ๐ฝ๐บ๐ฒ๐ป๐ ๐ฎ๐ป๐ฑ ๐ฆ๐ง๐ฅ๐๐ง๐๐๐๐ ๐ฐ๐ผ๐ป๐๐๐น๐๐ถ๐ป๐ด ๐ฅ +175 projects, +20M in revenue, +3M in funds raised ๐๐น๐น ๐ผ๐ณ ๐๐ต๐ฒ๐บ ๐๐ฎ๐ธ๐ฒ๐ป ๐๐ต๐ฟ๐ผ๐๐ด๐ต ๐บ๐ ๐-๐ญ ๐ฝ๐ฟ๐ผ๐ฐ๐ฒ๐๐ ๐๐ผ ๐ฐ๐ฟ๐ฒ๐ฎ๐๐ฒ ๐๐ต๐ฒ ๐ฏ๐ฒ๐๐ ๐๐ฒ๐ฐ๐ต๐ป๐ผ๐น๐ผ๐ด๐ ๐ฎ๐ป๐ฑ ๐ถ๐ป๐ณ๐ฟ๐ฎ๐๐๐ฟ๐๐ฐ๐๐๐ฟ๐ฒ ๐ฒ๐ป๐๐๐ฟ๐ถ๐ป๐ด ๐๐ฒ๐ฐ๐๐ฟ๐ถ๐๐ & ๐ฒ๐ณ๐ณ๐ถ๐ฐ๐ถ๐ฒ๐ป๐ฐ๐. ๐ฏ "๐๐ค ๐ฆ๐ช๐๐จ๐ฉ๐๐ค๐ฃ๐จ ๐๐จ๐ ๐๐, ๐ฉ๐๐๐จ ๐๐ช๐ฎ ๐๐จ ๐ฉ๐๐ ๐๐๐จ๐ฉ ๐ค๐ ๐ฉ๐๐ ๐๐๐จ๐ฉ. ๐ ๐๐๐ซ๐ ๐๐ค๐ฃ๐ ๐ ๐ซ๐๐ง๐ฎ ๐ฉ๐๐ค๐ง๐ค๐ช๐๐ ๐ง๐๐จ๐๐๐ง๐๐ (๐๐ค๐ง ๐ฌ๐๐๐ ๐จ!) ๐ฉ๐ค ๐๐๐ฃ๐ ๐ ๐ง๐๐๐ก๐ก๐ฎ ๐๐ค๐ค๐ ๐๐ก๐ค๐๐ ๐๐๐๐๐ฃ ๐๐๐ซ๐๐ก๐ค๐ฅ๐ฅ๐๐ง, ๐๐ฃ๐ ๐๐ ๐๐ญ๐๐๐๐๐๐ ๐ข๐ฎ ๐๐ญ๐ฅ๐๐๐ฉ๐๐ฉ๐๐ค๐ฃ๐จ 1000%. ๐๐ค๐ฉ ๐ค๐ฃ๐ก๐ฎ ๐๐ ๐๐จ ๐ซ๐๐ง๐ฎ ๐ฅ๐ง๐ค๐๐๐จ๐จ๐๐ค๐ฃ๐๐ก ๐๐ฃ๐ ๐จ๐ ๐๐ก๐ก๐๐ ๐ฌ๐๐๐ฃ ๐๐ฉ ๐๐ค๐ข๐๐จ ๐ฉ๐ค ๐๐ช๐จ๐ฉ๐ค๐ข๐๐ฏ๐ ๐จ๐ข๐๐ง๐ฉ ๐๐ค๐ฃ๐ฉ๐ง๐๐๐ฉ๐จ, ๐ข๐๐ฃ๐ฉ๐๐ฃ๐ ๐ฌ๐๐๐จ๐๐ฉ๐๐จ, ๐๐ช๐ก๐ ๐ช๐ฅ๐ก๐ค๐๐๐จ ๐ฉ๐ค ๐ค๐ฅ๐๐ฃ๐จ๐๐, ๐จ๐๐ฉ๐ฉ๐๐ฃ๐ ๐จ๐๐ง๐ซ๐๐ง๐จ ๐๐ฉ๐, ๐๐ช๐ฉ ๐๐ ๐๐จ ๐๐ก๐จ๐ค ๐ซ๐๐ง๐ฎ ๐ฃ๐๐๐, ๐ฅ๐๐ฉ๐๐๐ฃ๐ฉ, ๐๐ฃ๐ ๐๐๐ก๐ฅ๐จ/๐๐๐ญ๐๐จ/๐๐๐๐ช๐จ๐ฉ๐จ ๐๐ช๐ง๐๐ฃ๐ ๐ฉ๐๐ ๐ฌ๐๐ค๐ก๐ ๐ฅ๐ง๐ค๐๐๐จ๐จ. ๐ ๐๐๐ง๐๐ ๐ ๐๐ค๐ฏ๐๐ฃ ๐ฅ๐๐ค๐ฅ๐ก๐ ๐๐ค๐ง ๐ข๐ฎ ๐๐๐ ๐ฅ๐ง๐ค๐๐๐๐ฉ, ๐๐ฃ๐ ๐ฉ๐๐๐จ ๐ฌ๐๐จ ๐๐ฎ ๐๐๐ง ๐ข๐ฎ ๐๐ง๐๐๐ฉ๐๐จ๐ฉ ๐๐ญ๐ฅ๐๐ง๐๐๐ฃ๐๐. ๐๐๐๐ฃ๐ ๐จ ๐ ๐ก๐ค๐ฉ ๐ผ๐ฃ๐๐ค๐ก ๐" โญ๏ธโญ๏ธโญ๏ธโญ๏ธโญ๏ธ ๐ฃ Tom Olssen - Vengeaful Beasts ๐ฃ ๐๐ถ๐ธ๐ฒ ๐๐ต๐ฎ๐ ๐๐ผ๐โ๐ฟ๐ฒ ๐ต๐ฒ๐ฎ๐ฟ๐ถ๐ป๐ด? ๐๐ป๐๐ถ๐๐ฒ ๐บ๐ฒ ๐๐ผ ๐๐ผ๐๐ฟ ๐ท๐ผ๐ฏ ๐ผ๐ป ๐จ๐ฝ๐๐ผ๐ฟ๐ธ ๐๐ผ ๐๐ฐ๐ต๐ฒ๐ฑ๐๐น๐ฒ ๐ฎ ๐๐ฅ๐๐ ๐ฑ๐ถ๐๐ฐ๐ผ๐๐ฒ๐ฟ๐ ๐ฐ๐ฎ๐น๐น ๐๐ผ ๐ณ๐ถ๐ป๐ฑ ๐ผ๐๐ ๐ถ๐ณ ๐๐ฒ ๐ฐ๐ฎ๐ป ๐ฏ๐๐ถ๐น๐ฑ ๐๐ผ๐บ๐ฒ๐๐ต๐ถ๐ป๐ด ๐ฎ๐บ๐ฎ๐๐ถ๐ป๐ด ๐๐ผ๐ด๐ฒ๐๐ต๐ฒ๐ฟ. ๐ ๐๐ฒ๐ฟ๐ฒโ๐ ๐๐ต๐ฎ๐ ๐๐ฒ๐๐ ๐บ๐ฒ ๐ฎ๐ฝ๐ฎ๐ฟ๐ ๐ณ๐ฟ๐ผ๐บ ๐ฎ๐ป๐๐ผ๐ป๐ฒ ๐ฒ๐น๐๐ฒ ๐๐ผ๐ ๐ฐ๐ผ๐๐น๐ฑ ๐ต๐ถ๐ฟ๐ฒ ๐๐ผ ๐ต๐ฒ๐น๐ฝ ๐๐ผ๐: ๐ธ I deliver exceptional results from the start. Many clients reach out to me after trying less experienced talent or in-house solutions that didnโt meet their expectations. By choosing me, youโre securing a product that will make you proud and run smoothly for years to come. ๐ธ Youโre never reliant on me to stay in control! My development approach emphasizes clear, ongoing communication and transparency. I ensure that you have full ownership and understanding of everything built. ๐ธ Working closely with Blockchain companies has allowed me to establish exclusive partnerships with some of the most prominent names in the Web3 industry. From Marketing, PR, Go-to-Market Strategy, and Tokenomics to NFT Strategy, Legal Structure Setup, VC Fundraising, and KOL, I offer comprehensive expertise. ๐ธ Security is never compromised. Too many times in the Web3 world we see projects getting shattered - funds stolen, servers crashing, trust from users lost. Thatโs why I include thorough quality assurance testing at every stage, with final checks before your product is delivered. ๐๐ป๐๐ถ๐๐ฒ ๐บ๐ฒ ๐๐ผ ๐๐ผ๐๐ฟ ๐ท๐ผ๐ฏ ๐ผ๐ป ๐จ๐ฝ๐๐ผ๐ฟ๐ธ ๐๐ผ ๐๐ฐ๐ต๐ฒ๐ฑ๐๐น๐ฒ ๐ฎ ๐๐ฅ๐๐ ๐ฑ๐ถ๐๐ฐ๐ผ๐๐ฒ๐ฟ๐ ๐ฐ๐ฎ๐น๐น ๐๐ผ ๐ณ๐ถ๐ป๐ฑ ๐ผ๐๐ ๐ถ๐ณ ๐๐ฒ ๐ฐ๐ฎ๐ป ๐ฏ๐๐ถ๐น๐ฑ ๐๐ผ๐บ๐ฒ๐๐ต๐ถ๐ป๐ด ๐ฎ๐บ๐ฎ๐๐ถ๐ป๐ด ๐๐ผ๐ด๐ฒ๐๐ต๐ฒ๐ฟ. ๐ ๐ฆ๐๐ฅ๐ฉ๐๐๐๐ฆ & ๐ฆ๐ข๐๐จ๐ง๐๐ข๐ก๐ฆ: โ Ethereum / Solana / BSC / Polygon (EVM) Customized Smart Contract Development โ Blockchain & Web3 Consultation (Smart Contract Ecosystem Design, Tokenomics, Whitepaper) โ EVM Smart Contract Audits (Automated Testing, Security Breach Search, Gas Efficiency, etc.) โ NFT Collection (ERC721 / ERC721A / ERC1155) creation (Whitelist, Shareholder Dividends, Burn mechanism, Reveal/Unreveal, Access Control, etc.) โ NFT Minting Dapps โ NFT Staking Contracts + Staking Dapps โ ERC20 Tokens (Basic Tokenomics, Staking Features, Buy Limits, Fees, etc.) + ICOs / IDOs โ DAOs โ NFT Marketplace โ Decentralized Exchange (Uniswap / Pancakeswap) โ Launchpad (Seedify) โ Yield Farming + DeFi Protocol โ Image & Metadata Generation Algorithm for NFT Artwork + IPFS Upload โ Solana NFT Smart Contract + Minting Dapp (Candymachine, Metaplex) โ 2D & 3D Graphic Design, Animations, and Promo Teaser Videos ๐ง๐๐๐ ๐ฆ๐ง๐๐๐: โ Solidity, Hardhat / Truffle / Remix, Slither, Ethereum / Binance / Polygon / Avalanche / Optimism / Solana โ React.JS + Next.JS (Web3.JS, ethersJS), AngularJS, HTML, CSS & JavaScript (jquery, Bootstrap) โ Node.js, NestJS, ExpressJS, Docker, Python, Amazon AWS, MongoDB, MySQL โ Figma, AdobeXD, PSD โ Github / Gitlab / Bitbucket, Slack, Trello / Notion / Clickup / Jira ๐๐ป๐๐ถ๐๐ฒ ๐บ๐ฒ ๐๐ผ ๐๐ผ๐๐ฟ ๐ท๐ผ๐ฏ ๐ผ๐ป ๐จ๐ฝ๐๐ผ๐ฟ๐ธ ๐๐ผ ๐๐ฐ๐ต๐ฒ๐ฑ๐๐น๐ฒ ๐ฎ ๐๐ฅ๐๐ ๐ฑ๐ถ๐๐ฐ๐ผ๐๐ฒ๐ฟ๐ ๐ฐ๐ฎ๐น๐น ๐๐ผ ๐ณ๐ถ๐ป๐ฑ ๐ผ๐๐ ๐ถ๐ณ ๐๐ฒ ๐ฐ๐ฎ๐ป ๐ฏ๐๐ถ๐น๐ฑ ๐๐ผ๐บ๐ฒ๐๐ต๐ถ๐ป๐ด ๐ฎ๐บ๐ฎ๐๐ถ๐ป๐ด ๐๐ผ๐ด๐ฒ๐๐ต๐ฒ๐ฟ. ๐
- Blockchain
- Blockchain Architecture
- Blockchain Development
- Ethereum
- Smart Contract
- Next.js
- React
- Cryptocurrency
- Node.js
- JavaScript
- Python
- Solana
- Solidity
- NFT
- API
Valencia, Spain
The main thing in programming is methodology not languages. Methodology is DRY, KISS, Patterns/AntiPatterns, Domain Driven Development, Clean Architecture, Test/Behaviour Driven Development and other development principles. Do you need an experienced developer, Web Service, API, Mobile / Desktop Application? Here is my presentation: โ I have over 15 years experience in different spheres of software development. If your ideas can be implemented, I will implement them for you in an impressive application. โ I am familiar with many different technologies and frameworks. I use the best of them to construct an architecture for robust application performance that is useful and gives users a pleasant experience. โ I am constantly improving my skills and learning new approaches and technologies. I provide clean, well documented, easily maintainable and extendable code for other developers. โ I am a team player who can take the lead in projects, work independently and work under the direction of others. I have reliable associates in different development spheres who can increase the speed of production by assisting in different stages of application deployment. โ I prefer long term collaboration because I like to be dedicated to one project at a time so that nothing else will interfere with the implementation of the idea. Skills: * Languages: C#, GoLang, TypeScript, JavaScript, PHP, Kotlin, Swift, Dart, Java, C, Objective-C, C++, Python * Backend: [own framework, CMS, API, etc.] , Laravel 4/5/6/7+, Symphony, Yii (I prefer them, but know many others) * Frontend: Vue.js, Angular, React, Twitter Bootstrap 3/4, Backbone.js, jQuery, Foundation, HTML5, CSS3, SASS, STYLUS, LESS * Databases: MySQL, PostgreSQL, SQLite, GraphQL, MongoDB, Firebase, etc. * Integration: PayPal, Stripe, Facebook, Twillo, Twitter, Google Maps, POS, RESTful, AJAX, JSON, SOAP, OAuth * Other stuff: ElasticSearch, Redis, Memcache, GitHub, Bitbucket, Git, Mercurial, Jira, Trello, YouTracker * Javascript stuff: Node.js, WebPack, Gulp 3/4 * Administration: Ubuntu, Linux, DigitalOcean, Amazon AWS(EC2, S3, RDS, Beanstalk, Lambda) * Blockchain development with GoLang * CI/CD: Docker, K8s, GitHub Actions, Fastlane, Codemagic Other: * Other javascript stuff: CasperJs, PhantomJs * Applies: Windows software, Linux software, Bots, Scrapers * Mobile: Android (Native), iOS (Native), Flutter, Cordova * Other stuff: Selenium WebDriver(ChromeDriver), Google APIs, Firebase Stuff * Software: Photoshop, Illustrator, CorelDraw, Sketch, 3ds Max * 3D: Unity3D (ECS, TDD, Reverse Engeneering), Unreal Engine, Three.js This is not a comprehensive list of my skill set, please enquire for further information.
- Team Building
- PHP
- Firebase
- Vue.js
- C#
- Team Management
- Front-End Development
- Full Production
- Flutter
- Laravel
- iOS Development
- Golang
- CI/CD
- API Development
- Software Architecture & Design
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Resources to help you hire

Cost to hire a Blockchain Developer
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Blockchain Developer job description template
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Blockchain Developer interview questions
Top interview questions to help you hire the right Blockchain developers, faster.
How do I hire a Blockchain Developer in Spain on Upwork?
You can hire a Blockchain Developer in Spain on Upwork in four simple steps:
- Create a job post tailored to your Blockchain Developer project scope. We'll walk you through the process step by step.
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- Once the proposals start flowing in, create a shortlist of top Blockchain Developer profiles and interview.
- Hire the right Blockchain Developer for your project from Upwork, the world's largest work marketplace.
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How much does it cost to hire a Blockchain Developer?
Rates charged by Blockchain Developers on Upwork can vary with a number of factors including experience, location, and market conditions. See hourly rates for in-demand skills on Upwork.
Why hire a Blockchain Developer in Spain on Upwork?
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Can I hire a Blockchain Developer in Spain within 24 hours on Upwork?
Depending on availability and the quality of your job post, it's entirely possible to sign up for Upwork and receive Blockchain Developer proposals within 24 hours of posting a job description.
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Top cities for Blockchain Developers in Spain
- VMware Administrators in Madrid, ES
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- SEO Experts in Madrid, ES
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- Sound Designers in Valencia, ES
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