Senior Solana Blockchain Engineer

Cheesecake Labs is a software design and development company that delivers digital products that drive business impact. Today, with more than 10 years of experience connected to Silicon Valley, Cheesecake Labs has delivered 300+ digital products for a diverse range of clients, from Fortune 500 to fast-growing startups, that have the challenge of innovating in the world’s most competitive markets. 
Among our clients, we have leading brands such as AB InBev, Singularity University, FINN and Tapcart. Our commitment to high-quality services has earned us recognition as the Top 1 Mobile Development company in Latin America and among the top 10 globally for Mobile App and Custom Software Development by Clutch and a GPTW-certified company for 10 years in a row.
The story behind this role
We’re continuously working with companies building ambitious digital products across Web2, Web3, AI, and emerging technologies. Many of our client engagements start with strategic conversations and evolve quickly into active projects. 
That’s why we maintain a network of strong contractor engineers we can engage quickly when the right projects come in.
This is not a traditional long-term internal role.It’s a contractor opportunity designed for people who enjoy working across different products, clients, technologies, and business challenges in fast-moving environments.
We’re looking for a Blockchain Engineer (Contractor) who enjoys solving complex technical problems, navigating ambiguity, and contributing to real-world products used by companies across the US and Europe.
Engagement details
Contractor / project-based engagement
Paid in USD/hour
Remote-first
Flexible allocation depending on project availability and fit
Opportunities may vary in duration, scope, and weekly commitment depending on client needs
Some opportunities may start immediately. Others may become active as new projects enter our pipeline.
What this role actually looks like
This is not a “receive tasks and code” type of role.
On a typical project, you might:
Build and evolve blockchain infrastructure services that power production-grade digital asset platforms
Work closely with team members to figure out what should actually be built
Integrate backend systems with Layer-1 blockchains, ensuring reliability, scalability, and operational resilience
Build services such as blockchain indexers, event processors, chain APIs, wallet services, and transaction pipelines
Design and improve blockchain workflows around transaction execution, event monitoring, reconciliation, and failure recovery
Make trade-offs between scalability, security, observability, maintainability, and business priorities
Collaborate with international clients and multidisciplinary teams to shape technical solutions for security-critical blockchain products
What tends to work well here
We’ve seen that people who thrive in this type of engagement usually:
Have strong experience building or integrating blockchain infrastructure in production environments
Understand Layer-1 blockchain mechanics such as transaction lifecycle, confirmations, finality, forks, reorgs, and event propagation
Feel comfortable building backend services, APIs, event-driven systems, and distributed architectures beyond the blockchain layer itself
Have a fullstack mindset — even if blockchain and backend are your strengths, you're comfortable navigating adjacent technologies and collaborating across the stack when needed
Enjoy solving complex infrastructure problems where security, observability, and reliability matter as much as feature delivery
Feel totally confident working in English with international clients and teams (calls, discussions, async) — at least advanced level
Already use AI as part of their day-to-day workflow — whether for protocol analysis, development, debugging, documentation, testing, or workflow acceleration
This probably won’t be your thing if
Just to be transparent:
You’re looking for a highly stable long-term internal role with fixed scope and predictable allocation
You prefer highly structured environments with rigid processes and very defined requirements
You’re uncomfortable navigating ambiguity or fast-changing technical contexts
You’d rather avoid client interaction or cross-functional collaboration
You dislike context-switching between technologies, projects, and business domains
There’s nothing wrong with any of that — it’s just not how these engagements usually operate.
One last thing
To participate in this selection process, you must:
Have a valid business registration in your country (CNPJ, VAT, EIN, or equivalent)
Have a bank account eligible to receive USD payments
Be able to issue invoices accordingly
Be based in the USA
These requirements are necessary for contractor engagement and payment processing.
Not sure if you check every box?
That’s okay. We know that many great people — especially from underrepresented groups — hesitate to apply unless they meet 100% of the requirements.If this opportunity sounds interesting, we’d still love to hear from you.
LINK TO APPY: https://cheesecakelabs.hire.trakstar.com/jobs/fk0zr7h/

About CKBA
The Common Knowledge Base Association (CKBA) ****is a Swiss Verein—a membership-based, non-profit entity governed by its contributors. It reflects the natural progression of the CKB ecosystem.
It brings together the same people and efforts that have shaped CKB from the start under a more aligned and effective structure.
Learn more about us:
Website: https://ckba.build
X: https://x.com/CKBAOfficial
LinkedIn: https://www.linkedin.com/company/common-knowledge-base-association/
GitHub: https://github.com/nervosnetwork/ckb
Forum: https://talk.nervos.org/
About the Role
Some of the most important ideas in blockchain are also the hardest to explain.
As a Senior Content Writer, you'll help bridge that gap by transforming complex protocol designs, technical concepts, and ecosystem developments into thoughtful, educational, and engaging content.
This is not a technical documentation role. Instead, we're looking for someone who understands blockchain technology deeply enough to explain it clearly to a broader audience.
If you enjoy researching complex topics, asking thoughtful questions, and crafting high-quality educational content, we'd love to hear from you.
Responsibilities
Research and write high-quality educational long-form articles about CKB, blockchain infrastructure, and related topics.
Translate protocol updates and complex technical concepts into clear, engaging content for broader audiences.
Write high-impact content for X, including posts, threads, long-form posts, and thought-leadership quote tweets.
Collaborate closely with researchers, engineers, and ecosystem contributors to ensure technical accuracy.
Review and edit content from other contributors to maintain a consistent editorial standard and tone.
Stay current with industry trends and contribute to broader ecosystem narratives where relevant.
Apply SEO and GEO best practices where appropriate.
Effectively leverage AI tools to improve research, drafting, editing, and writing workflows while maintaining high editorial quality.
Qualifications
Required
4+ years of professional writing experience (7+ years preferred).
Deep understanding of blockchain technology and the broader crypto ecosystem.
Proven ability to explain complex technical concepts in a way that is accurate, engaging, and accessible.
Exceptional written English with strong attention to clarity, structure, and detail. Native-level proficiency is preferred but not required.
Excellent research skills and intellectual curiosity.
Experience writing educational, technical, or research-driven long-form content.
Experience creating engaging content for X (Twitter), including threads and thought-leadership content.
Familiarity with SEO/GEO principles and AI-assisted writing workflows.
Preferred
Experience working with an L1, L2, major DeFi protocol, blockchain infrastructure project, or centralized exchange.
Background in editorial, journalism, research communications, or educational content.
Experience reviewing and editing the work of other writers.
This role is probably not the right fit if your experience has been primarily focused on news reporting, market analysis, or short-form marketing copy.
Application
Please send your application to join@ckba.build with the subject line:
Senior Content Writer – Your Name
Please include:
Your resume
Three writing samples that best represent your work
Ideally, your writing samples should be educational, technical, or research-driven long-form articles (1,000+ words) that demonstrate your ability to explain complex ideas clearly. News articles, market analysis, newsletters, or primarily promotional content are generally not the best examples for this role.
If you've collaborated with others on a piece, please briefly describe your contribution.
Writing is the most important part of our evaluation process. We'd much rather read your best work than a long list of previous employers. If you're an exceptional writer who enjoys explaining complex ideas, we'd still love to hear from you—even if you don't meet some qualification listed above.

About the Role
We are seeking a Senior Solidity Engineer to design, develop, audit, and optimize high-performance smart contracts on Ethereum and EVM-compatible chains. As a senior contributor, you will lead critical protocol development, mentor junior engineers, and ensure our on-chain systems are secure, gas-efficient, scalable, and production-ready in a fast-moving Web3 environment.
Key Responsibilities
Architect and implement complex smart contracts using Solidity for DeFi protocols, NFTs, governance systems, bridges, oracles, and other blockchain primitives.
Conduct thorough security reviews, formal verification where applicable, and collaborate with external auditors.
Optimize contracts for gas efficiency, security, and maintainability.
Integrate smart contracts with front-end applications, off-chain services, indexing solutions (The Graph, Subsquid), and cross-chain infrastructure.
Develop and maintain comprehensive test suites (unit, integration, fuzzing, and invariant testing).
Participate in code reviews, architectural decisions, and technical roadmap planning.
Mentor mid-level and junior engineers on best practices, security patterns, and Solidity internals.
Monitor deployed contracts, respond to incidents, and implement post-deployment upgrades (via proxies where applicable).
Stay current with EVM upgrades (e.g., Prague/Electra), L2 scaling solutions (Optimism, Arbitrum, zkSync, etc.), and emerging standards (ERC-xxx, Account Abstraction).
Required Qualifications (Must-Have)
1-3 years of professional experience in Solidity development with a proven track record of deploying secure, audited smart contracts to mainnet.
Deep mastery of Solidity (v0.8.x+), including advanced patterns (reentrancy guards, upgradeable proxies – UUPS/Transparent, diamond pattern, libraries).
Strong understanding of EVM internals, gas optimization techniques, and security vulnerabilities (SWC registry, common attack vectors).
Proficiency with smart contract testing frameworks: Foundry (preferred) or Hardhat + ethers.js/waffle.
Experience with formal verification tools (Certora, Slither, MythX) and static analysis.
Solid experience in at least one major Web3 domain: DeFi (AMM, lending, derivatives), NFTs/marketplaces, RWA, or infrastructure (bridges, account abstraction).
Strong TypeScript/JavaScript skills for tooling and integration.
Experience working with Layer 2 solutions and cross-chain messaging protocols.
Excellent written and verbal communication skills; ability to write clear technical documentation (NatSpec, architecture decision records).
Track record of contributing to open-source projects or public GitHub repositories (please share links).
Preferred Qualifications (Strong Plus)
Previous experience at a top-tier Web3 protocol, audit firm (e.g., Trail of Bits, OpenZeppelin), or high-profile DeFi project.
Knowledge of Rust or other languages for blockchain development (bonus for familiarity with zk-proofs or Move).
Experience with Account Abstraction (ERC-4337), intent-based architectures, or MEV mitigation.
Familiarity with governance frameworks (Governor, Tally) and tokenomics design.
Contributions to standards (EIPs) or participation in Ethereum core dev calls.
Security researcher background or history of responsible disclosure.
What We Offer
Competitive compensation (base + significant token equity).
Fully remote-friendly with flexible hours.
Opportunity to work on cutting-edge blockchain infrastructure with real user impact.
Budget for conferences, security tooling, and continuous learning.
Collaborative, high-trust engineering culture.

About the Role
We are building a next-generation Web3 social platform designed to redefine how digital communities connect, collaborate, and grow.
Backed by years of experience within the cryptocurrency, blockchain, and digital asset ecosystem, our team has developed deep insights into how founders, developers, investors, creators, and communities interact. This understanding inspired us to create a platform that goes beyond financial applications and focuses on empowering meaningful social engagement.
Our mission is to build a transparent, community-driven social network where users can share ideas, collaborate on projects, discover opportunities, and create lasting relationships. We believe the next evolution of social media will be powered by decentralized technologies while maintaining an exceptional user experience, simplicity, and long-term sustainability.
We are seeking an experienced Chief Technology Officer (CTO) or Senior Full-Stack Developer who is passionate about Web3 and capable of leading the technical vision, architecture, and execution of our platform from the ground up.
Responsibilities
Lead the technical strategy and product architecture.
Design and build scalable backend systems and modern frontend applications.
Develop high-performance APIs and real-time features.
Integrate blockchain technologies, wallets, and Web3 authentication where appropriate.
Build secure, reliable, and maintainable infrastructure.
Collaborate closely with product, design, and leadership teams.
Establish engineering best practices, code quality standards, and development workflows.
Mentor engineers and help grow the technical organization.
Evaluate emerging technologies and implement solutions that improve scalability, security, and user experience.
Requirements
5+ years of professional software development experience.
Strong experience with modern JavaScript/TypeScript ecosystems.
Experience with React, Next.js, Node.js, or similar technologies.
Solid understanding of system architecture, cloud infrastructure, databases, and API design.
Experience building scalable consumer-facing products.
Familiarity with blockchain technologies, Web3 infrastructure, wallets, smart contracts, or decentralized applications.
Strong knowledge of security best practices and application performance optimization.
Excellent problem-solving and communication skills.
Ability to work independently in a fast-paced startup environment.
Preferred Qualifications
Experience building Web3 or crypto products.
Understanding of decentralized identity, token ecosystems, or on-chain social applications.
Experience leading engineering teams or serving in a technical leadership role.
Background in DevOps, CI/CD, Docker, Kubernetes, or cloud platforms such as AWS or GCP.
Experience with real-time messaging, social platforms, or community products.
What We Offer
Competitive full-time compensation.
Opportunity to build a product from an early stage with significant technical ownership.
Flexible and remote-friendly work environment.
Collaborative team focused on innovation and long-term impact.
Work on cutting-edge Web3 technologies and help shape the future of digital communities.
Opportunity for career growth and leadership as the platform scales.
If you are excited about building the next generation of Web3 social experiences and want to make a meaningful impact from the earliest stages, we'd love to hear from you.

Merklio is developing a private order-book aggregator using zero-knowledge proofs. We need a ZK-Infrastructure Engineer to build our proof generation pipeline and optimize proving times for complex circuits.
Expectations:
Design and implement circuits for merkle membership and signature aggregation
Optimize witness generation and prover memory usage
Build a distributed prover system with load balancing
Reduce proving time from 30s to <5s using GPU acceleration
Collaborate with researchers on new polynomial commitment schemes
Write performance benchmarks and regression tests
Deploy provers as microservices on Kubernetes
Maintain a devnet for testing with real transaction data
Contribute to open-source ZK libraries (e.g., gnark, arkworks)
Nice to have:
Experience with MPC (multi-party computation)
Knowledge of TLSNotary or ZKEmail
Published papers or talks at ZK conferences
Chinese+English language proficiency