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Pinnacle Digital Services

4.9

6.6

100%

Wollert, Australia

$20 USD per hour

Hi, I’m Jaffer – welcome to Pinnacle Digital Services! At Pinnacle Digital Services, we specialize in crafting high-quality mobile apps, websites, and desktop applications tailored to your unique needs. Our mission is simple: to deliver innovative, results-driven solutions that go beyond expectations. By combining deep technical expertise with a client-centric approach, we ensure every project is aligned with your vision and business goals. Why Choose Pinnacle Digital Services? We’re committed to excellence in every detail. From our first conversation to final delivery and ongoing support, your satisfaction is our priority. We believe in long-term partnerships built on trust, transparency, and collaboration—helping you grow while we grow with you. Our Core Services & Expertise: Web Development Technologies: PHP, MySQL, HTML5, CSS, jQuery, Node.js, Vue.js Frameworks: CodeIgniter, Laravel, CakePHP Mobile App Development Android: Java, Kotlin iOS: Swift Desktop Application Development Languages: Java/JavaFX, C/C++, C#, Python, Matlab, Let’s Build Something Great Together Whether you're launching a startup, streamlining operations, or taking your brand to the next level, we’re ready to turn your ideas into impactful digital experiences. Have questions or a project in mind? Reach out—our dedicated team is always here to help you succeed.

Web3.js PHP C Programming Java JavaScript

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Muhammad A.

4.7

5.7

97%

Perth, Australia

$50 USD per hour

I provide complete IT services tailored to modern business needs, with a strong focus on Blockchain development, Artificial Intelligence, Machine Learning, Big Data, Web and Mobile app development, E-commerce platforms, and custom software solutions. I specialize in blockchain technologies including DEXs, DApps, NFTs, Web3, smart contracts, and DeFi applications across platforms like Ethereum, BSC, and Polygon. For web and mobile development, I work with Java, Python, PHP, and top JavaScript frameworks such as React.js, Node.js, Angular, and Vue.js—alongside mobile technologies like Flutter and React Native. My e-commerce solutions are built on platforms like WooCommerce, Shopify, and Magento, while my AI and machine learning services leverage tools such as TensorFlow and AWS to create intelligent, data-driven systems. If you're looking for secure blockchain integration, modern web and mobile development, scalable e-commerce systems, or custom AI-driven software, I’m here to help turn your ideas into powerful digital products.

Web3.js PHP C Programming Java JavaScript

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Sijan A.

5.0

5.8

96%

Riverwood, Australia

$25 USD per hour

I am an expert in - AWS including autoscaling, high availability, data transfer - Blockchain infrastructure setup - Moodle hosting, management, administration - Cloud infrastructure - Install and configure Elasticsearch, Kibana, Logstash, Beats, APM - Linux administration (Ubuntu, Redhat, CentOS, SUSE, Kali, Debian, etc.) - Automation using Ansible - MySQL, MySQL Cluster administration, migration, backup/restore - PostgreSQL administration, migration, backup/restore - Cryptography - SSL, certificate, public-key infrastructure, cryptography - Oodo ERP, NextCloud - cPanel, Plesk - Optimise WordPress performance, Joomla, Drupal - Acronis, Splunk, security - FreeRadius (RADIUS) - Ethical hacking And many other stuff in technology. Please reach out to me if you need any help with regard to information technology issues.

Web3.js PHP System Admin Linux Excel

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Alesha A.

4.1

5.9

90%

EVANSTON, Australia

$50 USD per hour

Hi, I am a software engineer based in Australia. I help businesses build, fix, and improve web applications, automation systems, and internal tools. My work includes bug fixing, feature development, API integration, admin dashboards, workflow automation, web scraping, and completing unfinished projects. I also help clean up and improve AI-generated code so it becomes reliable, maintainable, and ready for real business use. I focus on practical solutions, clear communication, and delivering results that actually work in production. I can help with: fixing bugs in existing apps adding new features to web platforms API and third-party integrations automation for repetitive business tasks dashboards and internal admin tools debugging and improving AI-generated code ongoing maintenance and support I aim to make the process smooth for clients by understanding the real problem, suggesting the right approach, and delivering clean, dependable work.

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How to hire a great freelance Web3.Js Developer

A Web3.js developer is a blockchain engineer who uses the Web3.js JavaScript library to connect web applications to Ethereum and EVM-compatible networks, enabling smart contract interaction, wallet integration, and on-chain transactions. Hiring a skilled Web3.js developer lets you ship decentralized applications, token dashboards, NFT marketplaces, and DeFi interfaces that talk reliably to the blockchain from a browser or Node.js backend.

What a Web3.js developer does

Web3.js is the original Ethereum JavaScript API, and a freelance Web3.js developer specializes in writing the client-side and server-side code that bridges your application with smart contracts deployed on Ethereum, Polygon, BNB Chain, Avalanche, Arbitrum, Optimism, and other EVM chains. They handle the full integration layer: provider setup, wallet connection, contract instantiation from ABIs, transaction signing, gas estimation, event subscription, and error handling.

Commercially, this work matters because the integration layer is where most dApps fail. Poor transaction handling, broken wallet flows, or unverified contract calls cost users funds and trust. A competent Web3.js developer writes resilient code that handles dropped connections, reorged blocks, failed transactions, and chain switches gracefully.

Services and deliverables

A freelance Web3.js developer typically delivers production-ready code, integration modules, and documentation. Common deliverables include:

Smart contract integration using ABIs and the web3.eth.Contract interface

Wallet connection flows for MetaMask, WalletConnect, Coinbase Wallet, and injected providers

Transaction lifecycle handling: signing, broadcasting, confirmation tracking, and receipt parsing

Event listeners and historical log queries using getPastEvents and subscriptions

ERC-20, ERC-721, and ERC-1155 token interactions including approvals, transfers, and minting

Gas estimation, EIP-1559 fee handling, and nonce management for backend signers

Multi-chain support with dynamic provider switching and chain ID validation

Backend services in Node.js for indexing, automated transactions, and webhook triggers

Front-end integration with React, Next.js, Vue, or Angular

Unit and integration tests with Mocha, Chai, Hardhat, or Truffle

Tools and stack

Web3.js developers usually work alongside a wider blockchain toolchain. Expect proficiency with:

Web3.js core library and its companion modules (web3-eth, web3-utils, web3-eth-contract)

Hardhat and Truffle for local development, deployment, and testing

Ganache or Anvil for local EVM forks

Infura, Alchemy, QuickNode, and self-hosted RPC nodes as providers

MetaMask, WalletConnect v2, and Web3Modal for wallet UX

Solidity for reading and debugging the contracts being integrated

Etherscan, Polygonscan, and Tenderly for transaction debugging

IPFS, Pinata, and Arweave for decentralized storage of metadata

The Graph for indexing on-chain data when raw RPC queries are too slow

Industries and use cases

Web3.js developers serve a wide range of blockchain-driven projects. Typical engagements include DeFi protocols building swap interfaces, lending dashboards, and yield aggregators; NFT marketplaces and minting sites that need ERC-721 and ERC-1155 integrations; GameFi studios connecting in-game economies to on-chain assets; DAO tooling for governance voting, treasury management, and proposal execution; token launch platforms running presales, vesting, and airdrops; and enterprise pilots tokenizing real-world assets, supply chain records, or loyalty programs on private EVM chains.

How to evaluate a Web3.js developer

Strong candidates demonstrate hands-on Ethereum experience, not just general JavaScript skills. Look for portfolio links to deployed dApps, public GitHub repositories with smart contract integrations, contract addresses you can verify on a block explorer, and a clear understanding of EVM mechanics. Confirm they can read Solidity well enough to debug failing transactions, and check that they have shipped projects on at least one mainnet, not only testnets.

Useful interview questions to copy:

How do you handle a transaction that is stuck due to a low gas price, and how would you implement a replacement transaction with Web3.js?

What is the difference between a call and a send when interacting with a contract method, and when would you use each?

How do you reliably listen for contract events across chain reorganizations, and how do you avoid duplicate processing?

How would you support EIP-1559 fee fields while keeping fallback compatibility for legacy chains?

Walk me through how you would integrate WalletConnect v2 alongside MetaMask in a single front end using Web3.js.

Ask for a small paid trial task, such as wiring up a token approval and transfer flow against a testnet contract, before committing to a long engagement.

Why hire Web3.js developers on Freelancer.com

Freelancer.com gives you access to a global pool of blockchain engineers, with profiles spanning solo Solidity-and-Web3 specialists, full-stack dApp developers, and small studios that handle smart contract audits alongside front-end integration. You can review verified portfolios, ratings, completion rates, and client reviews before you shortlist. Milestone Payments protect your funds until each deliverable is approved, and the platform's chat and file-sharing tools keep ABIs, contract addresses, and design specs organized in one place. Whether you need a one-week wallet integration or a multi-month dApp build, freelancers on Freelancer.com are ready to bid on your scope.

Post a project on Freelancer.com today and connect with skilled Web3.js developers ready to build, integrate, and ship your decentralized application.

What are the steps to hiring a freelance Web3.js developer?

Hiring the right Web3.js developer comes down to writing a precise brief, reading bids critically, and verifying on-chain experience before you award. The steps below walk you through the process and the specific signals that matter for blockchain integration work.

Step 1: Post your project on Freelancer.com

The brief is the single biggest determinant of bid quality, because Web3.js work is technical and ambiguous scopes attract mismatched candidates. Head to the post project page , fill in the scope, timeline, and budget, and publish your project for freelancers to bid on. The clearer you are about chains, contracts, and front-end stack, the more relevant your bids will be.

List the target chains and networks (mainnet, testnets, Layer 2s)

Share contract ABIs, addresses, or Solidity source if available

Specify the front-end framework (React, Next.js, Vue) and any existing wallet libraries

Describe the user flows: minting, swapping, staking, governance voting, or token transfers

State whether you need backend signing, event indexing, or only client-side integration

Indicate timeline expectations and any audit or testing requirements

Step 2: Review bids from freelancers

Bids are short proposals, not just price quotes. A strong Web3.js bid will reference your specific chains, ask about contract details, and propose an approach for transaction handling, error states, and wallet support. Read each proposal carefully and shortlist developers who clearly understood the brief.

Look for technical questions about ABIs, gas strategy, or chain support that show real engagement with your scope

Check that the proposed approach mentions specific Web3.js methods, providers, or wallet libraries

Assess timeline realism against the complexity of the contract interactions you described

Review attached samples of dApps, GitHub repositories, or deployed contract addresses

Use Freelancer.com chat to ask clarifying questions about EIP-1559 handling, event listening, or multi-chain switching before shortlisting

Step 3: Evaluate freelancers and award the project

Final selection combines proposal quality with profile evidence. For Web3.js work, consistency matters more than a single flashy project, because reliable transaction handling shows up across many small builds. Verify that the freelancer has shipped to mainnet, not just demos.

Review portfolio depth: number of dApps shipped, chains worked on, and contract types integrated

Check star ratings and the volume of completed projects relevant to blockchain or JavaScript

Read written client reviews for signals on communication, debugging skill, and on-time delivery

Confirm verified payment method, completion rate, and on-time delivery rate on the profile

Award the project and use Freelancer.com Milestone Payments to release funds only as integration milestones such as wallet connection, contract calls, and event handling are delivered and tested

What is the difference between Web3.js and Ethers.js?

Web3.js and Ethers.js are both JavaScript libraries for interacting with Ethereum, but they have different APIs and design philosophies. Web3.js is the original library with a broader feature set and long-standing community adoption, while Ethers.js is more modular and lightweight. Many developers are fluent in both, so confirm which library your existing codebase uses before hiring.

Do I need a Web3.js developer or a Solidity developer?

You need a Solidity developer to write and deploy smart contracts, and a Web3.js developer to connect your application to those contracts. Many freelancers do both, especially on smaller projects, but on larger builds it is common to split the roles so each specialist focuses on their layer.

Can a Web3.js developer work with chains other than Ethereum?

Yes. Web3.js works with any EVM-compatible network, including Polygon, BNB Chain, Avalanche C-Chain, Arbitrum, Optimism, Base, and private enterprise chains. The developer simply points the library at the appropriate RPC endpoint and chain ID.

How long does a typical Web3.js integration project take?

A focused integration like wallet connection plus a single contract flow can take a few days, while a full dApp front end with multi-chain support, event indexing, and transaction history can take several weeks. Timeline depends on contract complexity, design scope, and how much testing is required across networks.

Can I hire a Web3.js developer for a one-off fix?

Yes. Many freelancers on Freelancer.com take on short bug fixes, audits of existing integrations, or feature add-ons such as adding a new chain, fixing a broken transaction flow, or migrating from a deprecated provider. Post a clear scope and you will receive bids from developers who can start quickly.