Blockchain development services
Blockchain development services: Solidity smart contracts on Ethereum and EVM chains, Solana programs in Rust, DeFi protocols, wallets, exchanges and trading infrastructure, NFTs and tokenised assets, zero-knowledge proofs and indexers, with dedicated blockchain developers for your team or a Web3 project delivered end to end.
What we build on blockchain
Solidity smart contracts
Contracts on Solidity 0.8 for Ethereum, Arbitrum, Base, OP Mainnet (Optimism), Polygon and BNB Chain, built on OpenZeppelin Contracts with Foundry or Hardhat, and upgradeable through UUPS proxies only where the design calls for it.
DeFi protocols
Lending markets, automated market makers and Uniswap v4 hooks, ERC-4626 vaults, staking and liquid staking, with prices from Chainlink or Pyth oracles and the liquidation and keeper bots that run off-chain.
Exchanges and trading infrastructure
Matching engines and order books, deposit and withdrawal flows across hot and cold wallets, market data and trading APIs over WebSocket and FIX, and DEX aggregation and market-making connectors.
Wallets and account abstraction
Browser-extension and mobile wallets, MPC and multisig custody through Safe or Fireblocks, and ERC-4337 smart accounts and EIP-7702 delegation with passkey sign-in and sponsored gas, connected to dApps through wagmi and viem.
Solana programs in Rust
Programs built with Anchor and Token Extensions, every account constraint checked explicitly, and tests run against a local validator before anything reaches devnet.
Indexers, subgraphs and data APIs
Subgraphs on The Graph, Substreams or Ponder, contract events decoded into PostgreSQL or ClickHouse for analytics and dashboards, and GraphQL or REST APIs with RPC failover across providers, so the application never queries a node for every page.
NFTs and tokenised assets
ERC-721 and ERC-1155 collections, compressed NFTs on Solana, NFT marketplaces, stablecoins, and permissioned ERC-3643 tokens for real-world assets with transfer rules and allowlists your compliance team can administer.
Zero-knowledge proofs and rollups
Circuits in Circom or Noir, programs proven in zkVMs such as SP1 and RISC Zero, on-chain verifiers, and rollups and appchains on the OP Stack or ZK Stack, or as Arbitrum chains (formerly Arbitrum Orbit).
Smart contract audit preparation
Fuzz and invariant tests in Foundry and Echidna, Slither and Aderyn in the pipeline, symbolic checks with Halmos, and a specification, threat model and test report handed to your audit firm, with every finding fixed and re-tested.
Hire blockchain developers
Dedicated blockchain developers
Blockchain developers who join your team full time, work in your tools and process, and report to your lead. You interview them; we carry the Ukrainian contract, payroll, invoicing and leave.
Blockchain development projects
A defined piece of blockchain development with a scope, a fixed plan and a named lead on our side who owns the result and reports progress in your channels.
Ongoing blockchain development
Blockchain development as a continuing service: the same people every month, a backlog you prioritise, and hours you can see in our portal and on the invoice.
The dedicated team page explains how specialists join your team, and the outsourcing page covers project delivery, take-overs and how we charge.
Who works on your blockchain development
Solidity developers
EVM contracts, Foundry and DeFi protocols
Rust developers
Solana programs, zero-knowledge circuits and node software
Backend engineers
Go, Node.js, .NET or Python indexers, exchange and wallet services
Front-end engineers
React and Next.js dApps with wagmi and viem
QA engineers
Test plans on testnets and forked mainnet before each release
How we work on blockchain projects
A deployed contract is hard to change and holds real value, so the work starts with a written specification and threat model. Contracts are tested with fuzzing and invariants as well as examples, deployments are scripted and rehearsed on a testnet, admin rights sit behind a multisig and a timelock, and an independent audit comes before mainnet.
Most of a blockchain product runs off-chain: the indexer, the API, the sign-in, the back office and the monitoring. That part follows the same rules as the rest of our work: infrastructure as code, tests in the pipeline, dependencies on current releases and secrets in a vault.
Other specialised development we provide
Full-stack development
Full-stack development services: web apps, SaaS products, marketplaces and portals on MERN, MEAN, Next.js, .NET, Laravel, Django, Spring Boot and Rails stacks, with dedicated full-stack developers or project delivery.
Desktop application development
Desktop application development services: Windows, macOS and Linux apps in Qt and C++, .NET, Electron, Tauri, Rust and Swift, plug-ins and .NET Framework upgrades, with dedicated desktop developers or project delivery.
Salesforce development
Salesforce development services: Sales, Service, Marketing, Commerce and Experience Cloud, Apex, LWC, CPQ, Data 360, Agentforce, MuleSoft and AppExchange apps, with dedicated Salesforce developers or project delivery.
Software architecture and fractional CTO
Software architecture and fractional CTO services: solution, cloud, data and security architecture for fintech, SaaS and e-commerce, reviews and due diligence, with dedicated software architects or project delivery.
Questions about blockchain development
Which chains do you build on?
Ethereum and EVM networks such as Arbitrum, Base, OP Mainnet, Polygon, BNB Chain and Avalanche, Solana, TON, Cosmos SDK chains, Bitcoin and the Lightning Network, Move-based chains such as Sui and Aptos, and permissioned networks on Besu (formerly Hyperledger Besu) when the participants are known. The choice follows your users, the fees and the assets involved.
Which industries do your blockchain developers work in?
Most often crypto exchanges and trading firms (matching engines, custody and market data), DeFi protocols (lending, trading and staking), wallet and custody providers, payments and fintech (stablecoin payments and on-chain settlement), and Web3 infrastructure (rollups, nodes, RPC and indexing). They also build tokenisation for asset managers and real estate, on-chain analytics for data products, and security tooling.
Do you prepare smart contracts for an audit?
Yes. Every contract we write is tested and reviewed, with fuzzing, invariant tests and static analysis in the pipeline. We prepare the code, the specification and the threat model for an independent audit firm and fix what it finds, and for a contract that will hold real value that audit comes before mainnet.
Can you add blockchain features to an existing product?
Yes. Wallet sign-in, stablecoin payments, token-gated access, on-chain records and NFT tickets or rewards can be added beside your existing backend, with the indexer and the API built by the same team and your current sign-in and data left in place.
How quickly can blockchain developers start?
When the right blockchain developer is available, the start is gated only by your interview and the NDA and IP assignment. Otherwise we run a search, which typically produces candidate profiles within two to three weeks, and nobody starts until you have said yes.
How do we hire blockchain developers through BigTree108?
Tell us the work, the seniority and the hours you need. We propose one or two people with their profiles, you interview them the way you would interview your own hire, and you sign one agreement with BIG TREE 108 LLC and receive one invoice a month.
Who owns the work they produce?
You do. Every specialist has a signed contract with BigTree108 that assigns all work product to the company, and our agreement with you assigns it onward. Code, designs and documents are delivered into your own repositories and tools, not kept where only we can change them.
Building on blockchain?
Tell us the chain, what the contracts must do and where the project stands. You get an answer within one business day: a plan, candidate profiles, or a recommendation on the chain and the architecture.