Blockchain Security Expert - Anti Defect Track
USA
Full time
Remote
Compensation is not specified
Role
Security Engineer
Description
About the Company
Founded in 2018 by professors from Yale University and Columbia University, CertiK is at the forefront of blockchain security, leveraging top-notch AI technology to secure and monitor blockchain protocols and smart contracts. Their goal is to safeguard the cyber world and bring cutting-edge innovations to enterprise applications, ensuring security and correctness in mission-critical operations. CertiK has gained significant trust in the blockchain security sector and is experiencing rapid growth, with high-profile clients and investors on board.
About the Position
As a Security Engineer at CertiK, the main focus will be on contributing to the company's security-related services at the intersection of cybersecurity and blockchain technology. Responsibilities include participating in security reviews, audits of smart contracts and blockchains, penetration testing, and verification processes. The role also involves identifying and analyzing vulnerabilities in smart contracts, developing feature code analysis tools, and staying up-to-date with the latest technology trends to enhance CertiK's security offerings.
Responsibilities
- Conduct audits for blockchain smart contracts, detecting and addressing security vulnerabilities.
- Define attack models for blockchain security evaluations.
- Develop tools for feature code analysis based on extracted insights from exploited code.
- Stay informed on analysis tools and emerging technologies in the sector.
Requirements
- Hold a bachelor’s degree or higher in a science or engineering field, along with a minimum of 3 years of work experience.
- Proficiency in languages like Solidity, Go, Rust, C++, Python, or Node.js is required, as well as a strong grasp of common algorithms.
- Familiarity with fundamental information security concepts is essential.
- Ability to operate effectively in an English-language working environment with strong communication skills.
- Passion for blockchain technology and a willingness to continuously learn and adapt.
Bonus Points
- Experience with maintaining or developing production pipelines.
- Knowledge of static code analysis methods like Syntax Analysis, Semantic Analysis, and Taint Analysis.
- Exposure to popular blockchain platforms such as Ethereum, Hyperledger, and Cosmos.
- Previous experience with blockchain smart contracts, security audits, and associated best practices.
- Hands-on experience evaluating risks for blockchain projects or analyzing on-chain security events.
The expected annual salary range for this position is $90,000 - $150,000, with the final compensation depending on the candidate's skills and experience. CertiK offers a comprehensive benefits package, including medical, vision, and dental insurance, a 401(k) plan, life insurance, flexible paid time off, and more.
CertiK is an equal opportunity employer, committed to diversity and inclusion in the workplace. Candidates with criminal histories will also be considered based on local and federal regulations.
Skills Required
CertiK
Website
www.certik.comCompany size
Not specified
Location
United States
Description
Not specified
Tatyana Khrustaleva
Senior Go Developer
Full time
Remote
Senior Go Developer (Crypto focus; remote) The company (name withheld till the interview stage) is a non-custodial staking, re-staking, and node hosting platform that delivers advanced, secure infrastructure for institutional and retail investors. With automated services and an intuitive interface, we simplify the process of running full nodes, masternodes, and validators across 77 Proof-of-Stake blockchain protocols, hosting tens of thousands of nodes globally.In addition, we contribute to the blockchain ecosystem by offering complimentary tools and RPC endpoints for over 100 blockchain protocols, enabling users and developers to engage with their preferred blockchain networks and build innovative solutions!We are seeking a strong Senior Go Developer with experience in cryptocurrency. Requirements:Cryptocurrency and Node Experience: Minimum 1.5–2 years of experience working in the cryptocurrency space, specifically with nodes.Extensive experience and expertise in Go development.Russian or Ukrainian language proficiency.Knowledge of Node.js is a plus.Experience working in a remote, asynchronous environment.Familiarity with Slack for communication and collaboration.Working hours:You may start your 8-hour working day between 7 and 11 am GMT+3. For example, from 9 am to 5 pm GMT+3, etc.Remote team spanning from Los Angeles to London to Dubai, with minimal calls and Slack-based communication & decision-making.The team consists of 6-10 members with a strong sense of commitment—many have been with us for over 7 years. What we offer:Full-time job (8 working hours per day, Monday-Friday).Remote work. You may be located in any country, just need a good Internet connection, a powerful computer to work from, and the opportunity to adjust your working schedule for the team.Be part of a fast-growing, highly respected company in the crypto industry.Stability. This is not project work, we consider only the candidates looking for a long-term commitment of 1.5+ years.Work autonomously with a team of like-minded professionals.Engage in challenging and innovative projects with cutting-edge blockchain technologies.Salary will be discussed during the interview. Paid in USDT. Application deadline: ASAPSelection process:1. Fill in the application form - attach your CV & a GitHub portfolio link;2. Have a Zoom interview with Hire5 Recruiter;3. Have a technical Zoom meeting with the developer from the company team;4. Have a quick Zoom interview with the CEO of the company;5. Get hired!
Payment in Crypto
Hazel Thomas
Web3 + Supabase Developer Needed to Complete BSC Testnet Waitlist & Staking Platform
Washington, USA
Washington, USA
Part time
Remote
📌 Job Description
We are building a production-ready Web3 waitlist and dashboard platform using Next.js 15 (App Router), BSC Testnet, Supabase, and Wagmi v2.
The core architecture, database schema, and feature roadmap are already defined. We are looking for an experienced developer to complete, polish, and harden the project.
This is not a prototype — the goal is a fully working, deployable system with clean code, security best practices, and proper Web3 UX.
🧩 Project Overview
The platform includes:
Wallet-based user registration (BSC Testnet only)
Automatic network detection & switching
Supabase-backed user management
Automatic virtual card generation (Bronze / Silver / Gold)
Token staking system with transaction logging
Referral system with rewards tracking
Dashboard with analytics & history
X (Twitter) OAuth integration
Discord bot with XP & invite tracking
A detailed README and database schema are already prepared.
✅ Responsibilities
You will be responsible for:
Completing and stabilizing the Next.js App Router implementation
Finalizing wallet connection & network enforcement (Chain ID 97)
Ensuring Supabase RLS policies are correct and secure
Implementing or completing:
Staking flows (stake, unstake, claim, emergency withdraw)
Referral tracking & reward logic
Dashboard analytics & transaction history
Finalizing X (Twitter) OAuth integration
Reviewing and improving overall code quality & structure
Fixing bugs, edge cases, and UX issues
Preparing the app for Railway deployment
(Bonus) Improving performance and Web3 UX
🛠 Tech Stack (Must-Have Experience)
Required:
Next.js 14/15 (App Router)
TypeScript
Wagmi v2 + WalletConnect
EVM chains (BSC preferred)
Supabase (Postgres, RLS, triggers, SQL functions)
Tailwind CSS
Web3 transaction handling & logging
Nice to Have:
Discord bot development (Node.js)
OAuth 2.0 (X / Twitter)
Smart contract interaction (staking contracts)
Framer Motion
shadcn/ui / Radix UI
🔒 Security Expectations
You must be comfortable with:
Wallet validation & chain enforcement
Preventing self-referrals & abuse
Transaction hash uniqueness checks
Secure handling of OAuth tokens
Supabase RLS & role-based access
📦 Deliverables
Fully working, deployable application
Clean, documented codebase
Verified Supabase schema & policies
Functional staking & referral systems
Deployment-ready build (Railway)
Basic handover documentation
⏳ Timeline
Estimated duration: 2–4 months
Start: Immediately
Potential for long-term collaboration
💰 Budget
Open to fixed-price or hourly
Please include:
Your estimated timeline
Relevant Web3 / Next.js projects
Any questions or suggestions to improve the system
🧠 How to Apply
When applying, please answer:
Have you built production Web3 apps with Next.js + Wagmi before?
Have you worked with Supabase RLS & SQL triggers?
Share 1–3 relevant projects (GitHub or live links)
What risks or improvements do you see in this architecture?
Generic proposals will be ignored.
We are building a production-ready Web3 waitlist and dashboard platform using Next.js 15 (App Router), BSC Testnet, Supabase, and Wagmi v2.
The core architecture, database schema, and feature roadmap are already defined. We are looking for an experienced developer to complete, polish, and harden the project.
This is not a prototype — the goal is a fully working, deployable system with clean code, security best practices, and proper Web3 UX.
🧩 Project Overview
The platform includes:
Wallet-based user registration (BSC Testnet only)
Automatic network detection & switching
Supabase-backed user management
Automatic virtual card generation (Bronze / Silver / Gold)
Token staking system with transaction logging
Referral system with rewards tracking
Dashboard with analytics & history
X (Twitter) OAuth integration
Discord bot with XP & invite tracking
A detailed README and database schema are already prepared.
✅ Responsibilities
You will be responsible for:
Completing and stabilizing the Next.js App Router implementation
Finalizing wallet connection & network enforcement (Chain ID 97)
Ensuring Supabase RLS policies are correct and secure
Implementing or completing:
Staking flows (stake, unstake, claim, emergency withdraw)
Referral tracking & reward logic
Dashboard analytics & transaction history
Finalizing X (Twitter) OAuth integration
Reviewing and improving overall code quality & structure
Fixing bugs, edge cases, and UX issues
Preparing the app for Railway deployment
(Bonus) Improving performance and Web3 UX
🛠 Tech Stack (Must-Have Experience)
Required:
Next.js 14/15 (App Router)
TypeScript
Wagmi v2 + WalletConnect
EVM chains (BSC preferred)
Supabase (Postgres, RLS, triggers, SQL functions)
Tailwind CSS
Web3 transaction handling & logging
Nice to Have:
Discord bot development (Node.js)
OAuth 2.0 (X / Twitter)
Smart contract interaction (staking contracts)
Framer Motion
shadcn/ui / Radix UI
🔒 Security Expectations
You must be comfortable with:
Wallet validation & chain enforcement
Preventing self-referrals & abuse
Transaction hash uniqueness checks
Secure handling of OAuth tokens
Supabase RLS & role-based access
📦 Deliverables
Fully working, deployable application
Clean, documented codebase
Verified Supabase schema & policies
Functional staking & referral systems
Deployment-ready build (Railway)
Basic handover documentation
⏳ Timeline
Estimated duration: 2–4 months
Start: Immediately
Potential for long-term collaboration
💰 Budget
Open to fixed-price or hourly
Please include:
Your estimated timeline
Relevant Web3 / Next.js projects
Any questions or suggestions to improve the system
🧠 How to Apply
When applying, please answer:
Have you built production Web3 apps with Next.js + Wagmi before?
Have you worked with Supabase RLS & SQL triggers?
Share 1–3 relevant projects (GitHub or live links)
What risks or improvements do you see in this architecture?
Generic proposals will be ignored.
Payment in Crypto
lucas martin
Senior Web3 / Crypto Trading Platform Developer
Full time
Remote
PumaPulse is launching a new standalone domain focused on building professional-grade crypto trading platforms and on-chain trading tools. We are seeking an experienced freelance Web3 developer to help design, build, and evolve a scalable trading product with commercialization potential.ResponsibilitiesDevelop crypto trading tools, bots, or SaaS platformsIntegrate with DEXs and on-chain protocols (e.g., Solana, Ethereum)Implement real-time blockchain data monitoring and trade executionEnsure security, performance, and MEV-aware designCollaborate on product roadmap, strategy, and future featuresRequirementsStrong experience in Web3 and DeFi developmentProven work with crypto trading bots or on-chain trading systemsExperience with at least one major blockchain ecosystemSolid understanding of smart contract interaction and security best practicesAbility to deliver production-ready code and communicate clearlyNice to HaveExperience productizing tools into SaaS platformsBackground in advanced trading strategies or MEVPrior work with VC-backed or early-stage Web3 projectsEngagementFreelance / contract roleCompetitive compensation based on experiencePotential for long-term collaborationApply with relevant Web3 projects, GitHub links, and availability.
Payment in Crypto
Austin Smart
Fullstack Developer Needed for Web3 Prediction Market Platform
Brooklyn, USA
Brooklyn, USA
Full time
Remote
Summary
We're looking for an experienced Blockchain / Full-Stack Developer to help build a production-ready MVP for a Web3 prediction marketplace.
We’ve already built a basic UI prototype using vibe coding. The goal now is to turn this prototype into a functional, scalable dApp with clean architecture and solid Web3 fundamentals.
This is not a tutorial or experimental project — We’re looking for someone who has real experience shipping blockchain/web3 products.
What You’ll Do
Review and improve an existing UI prototype
Build smart contract logic for a prediction marketplace MVP
Integrate blockchain functionality with the frontend
Develop backend / API logic as needed
Ensure clean, maintainable, production-ready code
Collaborate on product decisions and MVP scope
Tech Stack (Preferred)
Frontend: Next.js / React
Backend: Node.js
Blockchain: Solidity / Rust
Experience with non-EVM chains is a plus (open to discussion)
What We're Looking For
- Strong experience in Blockchain & Web3 development
- Proven ability to build production-ready dApps
- Proficiency in Next.js, React, and Node.js
- Experience designing and shipping MVPs
- Good communication and ability to work independently
Nice to Have
- Previous work on prediction markets, DeFi, or marketplaces
- Experience taking projects from prototype to launch
- Performance, security, and scalability mindset
How to Apply
Please include:
- A brief summary of your Web3 experience
- Links to previous dApps or blockchain projects
- Your preferred tech stack and availability
If you’re an expert in blockchain and Web3 and enjoy building real products from early prototypes, We’d love to hear from you.
We're looking for an experienced Blockchain / Full-Stack Developer to help build a production-ready MVP for a Web3 prediction marketplace.
We’ve already built a basic UI prototype using vibe coding. The goal now is to turn this prototype into a functional, scalable dApp with clean architecture and solid Web3 fundamentals.
This is not a tutorial or experimental project — We’re looking for someone who has real experience shipping blockchain/web3 products.
What You’ll Do
Review and improve an existing UI prototype
Build smart contract logic for a prediction marketplace MVP
Integrate blockchain functionality with the frontend
Develop backend / API logic as needed
Ensure clean, maintainable, production-ready code
Collaborate on product decisions and MVP scope
Tech Stack (Preferred)
Frontend: Next.js / React
Backend: Node.js
Blockchain: Solidity / Rust
Experience with non-EVM chains is a plus (open to discussion)
What We're Looking For
- Strong experience in Blockchain & Web3 development
- Proven ability to build production-ready dApps
- Proficiency in Next.js, React, and Node.js
- Experience designing and shipping MVPs
- Good communication and ability to work independently
Nice to Have
- Previous work on prediction markets, DeFi, or marketplaces
- Experience taking projects from prototype to launch
- Performance, security, and scalability mindset
How to Apply
Please include:
- A brief summary of your Web3 experience
- Links to previous dApps or blockchain projects
- Your preferred tech stack and availability
If you’re an expert in blockchain and Web3 and enjoy building real products from early prototypes, We’d love to hear from you.
Payment in Crypto
Emir Hammami
Looking for a blockchain developer
Whiteman Air Force Base, USA
Whiteman Air Force Base, USA
Full time
Remote
We are looking for a skilled Full-Stack Blockchain Developer to help maintain, improve, and extend the RaiseHive platform. This role involves working across the frontend, backend, and smart contract layers to ensure a stable, secure, and scalable Web3 application.
The ideal candidate has hands-on experience with React, Node.js, Ethereum smart contracts, and real-world Web3 integrations.
Framework: React 18.2 (Vite 3)
Styling: Tailwind CSS 3.4, NextUI
Animations: Framer Motion
Web3: Thirdweb SDK v4, Ethers.js v5
Routing: React Router DOM v6
State Management: React Context API
Libraries: React Markdown, React Image Gallery, Replyke (comments), React Toastify
Runtime: Node.js
Framework: Express.js
Database: MongoDB Atlas (Mongoose ODM)
Email: Nodemailer
Scheduling: Node-cron
Logging: Pino
Network: Ethereum
Smart Contracts: Solidity ^0.8.19
Development Tools: Hardhat
Libraries: OpenZeppelin, Thirdweb Contracts
Wallet Integration: MetaMask
Frontend
Strong proficiency in React (hooks, context, routing)
Experience with Vite or modern build tools
Solid knowledge of Tailwind CSS and responsive design
Experience using component libraries (NextUI, Material UI, etc.)
Backend
Strong experience with Node.js and Express
Proficiency with MongoDB and Mongoose
REST API design and implementation
Environment configuration and deployment awareness
Blockchain & Web3
Hands-on Ethereum development experience
Solidity smart contract development
Experience with Ethers.js / Thirdweb SDK
Understanding of smart contract security and gas optimization
MetaMask wallet integration and transaction handling
General
JavaScript (ES6+)
Git version control
Async programming and debugging skills
Strong problem-solving ability
The ideal candidate has hands-on experience with React, Node.js, Ethereum smart contracts, and real-world Web3 integrations.
Framework: React 18.2 (Vite 3)
Styling: Tailwind CSS 3.4, NextUI
Animations: Framer Motion
Web3: Thirdweb SDK v4, Ethers.js v5
Routing: React Router DOM v6
State Management: React Context API
Libraries: React Markdown, React Image Gallery, Replyke (comments), React Toastify
Runtime: Node.js
Framework: Express.js
Database: MongoDB Atlas (Mongoose ODM)
Email: Nodemailer
Scheduling: Node-cron
Logging: Pino
Network: Ethereum
Smart Contracts: Solidity ^0.8.19
Development Tools: Hardhat
Libraries: OpenZeppelin, Thirdweb Contracts
Wallet Integration: MetaMask
Frontend
Strong proficiency in React (hooks, context, routing)
Experience with Vite or modern build tools
Solid knowledge of Tailwind CSS and responsive design
Experience using component libraries (NextUI, Material UI, etc.)
Backend
Strong experience with Node.js and Express
Proficiency with MongoDB and Mongoose
REST API design and implementation
Environment configuration and deployment awareness
Blockchain & Web3
Hands-on Ethereum development experience
Solidity smart contract development
Experience with Ethers.js / Thirdweb SDK
Understanding of smart contract security and gas optimization
MetaMask wallet integration and transaction handling
General
JavaScript (ES6+)
Git version control
Async programming and debugging skills
Strong problem-solving ability
Payment in Crypto