DEV.co
Blockchain Development Services

Blockchain software, engineered by senior developers.

The blockchain and distributed ledgers (DLTs) are new technologies with almost unlimited potential. Capitalize on higher automation, stronger security, and real transparency — with smart contracts, dApps, and Web3 systems built to last.

Solidity · EVM · Smart Contracts · dApps · DeFi · Web3 · Hyperledger · Layer-2
EVM + Non-EVM
Ethereum, Polygon, Arbitrum, Base, Solana & more
Solidity · Rust
Smart contracts written, tested, and audited
L1 + L2
Layer-1 protocols and Layer-2 scaling solutions
Audited
Secure patterns, fuzz testing, and gas optimization

What is the blockchain?

A “blockchain” is essentially a group of computers where information is stored and distributed. Rather than keeping everything on a central server, the information is decentralized — distributed and replicated across a network of peers.

Each participant (a node) holds a copy of the ledger, and new transactions are grouped into blocks that are cryptographically linked to the ones before them. A consensus mechanism — proof-of-work, proof-of-stake, or a permissioned validator set — keeps every copy in agreement, while cryptographic hashing makes the history practically immutable and tamper-evident.

Built properly, a blockchain enables higher levels of privacy, greater security, and higher productivity. It powers everything from finance and DeFi to healthcare records, supply-chain provenance, and the management of public records. The blockchain's potential is limited only by your imagination and the blockchain developer you work with — with the right ideas and the right partner, you could transform your entire industry.

Our blockchain development services.

From a single smart contract to a full decentralized application, our blockchain developers cover the entire distributed-ledger stack.

On-chain logic

Smart contract development

Solidity and Vyper contracts for the EVM — designed with secure patterns, thoroughly tested, gas-optimized, and audit-ready.

Hybrid systems

Hybrid & permissioned blockchains

Production of hybrid systems that blend blockchain with centralized elements, plus permissioned networks on Hyperledger Fabric.

Consulting

Product design consultations

Architecture, chain selection, and tokenomics guidance so your distributed-ledger product is viable before a line of code ships.

Integrations

Blockchain network integrations

Connect existing systems to on-chain data via Web3 APIs, oracles (Chainlink), indexers (The Graph), and event listeners.

dApps

DApp design & development

End-to-end decentralized applications with Web3 frontends (ethers.js), wallet integration (MetaMask, WalletConnect), and on-chain backends.

Access models

Permissioned & permissionless

Public, permissionless chains for open composability — or private, permissioned ledgers with known validators for enterprise consortia.

Advisory

Blockchain technology consultations

Strategy sessions on consensus, scalability, Layer-2 rollups, security, and regulatory exposure for your roadmap.

Migration

Migration & integration

Migrate and integrate new blockchain systems into existing infrastructure with zero-downtime cutover and clear documentation.

How it fits together

A reference blockchain architecture.

Clean separation between the wallet, the dApp frontend, the smart-contract layer, and the protocol and node infrastructure beneath it.

Each tier is independently maintainable — whether you're shipping a single smart contract or a full DeFi protocol with oracles and indexing.

The heart of every dApp

Smart contracts are immutable. We build them like it matters.

Once a smart contract is deployed on-chain it can't be quietly patched — and it often custodies real value. That raises the bar on engineering discipline. Our blockchain developers write in Solidity and Vyper using battle-tested patterns: checks-effects-interactions, reentrancy guards, least-privilege access control, and pull-over-push payments.

Every contract is covered by unit and fuzz tests in Foundry and Hardhat, run through static analysis with Slither, and gas-optimized so your users aren't punished at transaction time. For high-value protocols we add upgradeable proxy patterns, timelocks, and coordinate independent third-party audits.

Scope a Smart Contract Build
Show, don't tell

What a secure smart contract looks like.

A minimal escrow on the EVM — access-controlled, reentrancy-safe, and event-logged so every state change is auditable on-chain.

Escrow.solsolidity
// SPDX-License-Identifier: MITpragma solidity ^0.8.24;import "@openzeppelin/contracts/security/ReentrancyGuard.sol";contract Escrow is ReentrancyGuard {  address public immutable buyer;  address public immutable seller;  uint256 public amount;  bool public released;  event Funded(address indexed buyer, uint256 amount);  event Released(address indexed seller, uint256 amount);  constructor(address _seller) payable {    buyer  = msg.sender;    seller = _seller;    amount = msg.value;    emit Funded(msg.sender, msg.value);  }  // Only the buyer can release; funds move once, safely.  function release() external nonReentrant {    require(msg.sender == buyer, "not buyer");    require(!released, "already released");    released = true;                       // effects before interaction    (bool ok, ) = seller.call{value: amount}("");    require(ok, "transfer failed");    emit Released(seller, amount);  }}
Why it holds up
access control → only buyer can release ✓
reentrancy → guarded + state-before-call ✓
auditability → Funded / Released events ✓
immutability → buyer & seller are immutable ✓
gas → single transfer, no loops ✓

Secure-by-default patterns — reentrancy guards, checks-effects-interactions, and event logging — are how on-chain code earns trust.

Choosing the right blockchain developer.

Blockchain developers are in short supply, but it's still prudent to be selective. The factors that matter most:

Experience

Proven on-chain track record

Blockchain is still relatively young, but with so much riding on execution, work with a partner who has shipped real distributed-ledger software — smart contracts, dApps, and integrations — to production.

Compliance

Regulatory & security fluency

Finance, healthcare, and other sensitive industries are bound by rules. Anti-money-laundering (AML), know-your-customer (KYC), and adherence to GDPR, HIPAA, FISMA, and PCI DSS standards are crucial to maintain.

Collaboration

Clear, proactive communication

Blockchain development is complex, so the best results come from a true partnership. Prioritize a developer who communicates clearly and proactively throughout the project.

Our blockchain development process.

At DEV.co, we follow a fluid process that ends with you running the blockchain systems and products you envisioned.

01

Gathering scope

Our blockchain developers work with you to identify your core needs and gather scope: What are you trying to achieve? Which chain and consensus model fit? What's the budget and timeline?

02

Collaborative strategy sessions

We work together to shape a strategy and workshop ideas — tokenomics, architecture, and trade-offs — that get you the outcomes you need before building begins.

03

Design & development

Once we agree on a direction, our developers design and build the smart contracts, dApp, and integrations that fit your vision — with tests and security baked in from day one.

04

Initial launch

After several rounds of testing on testnets — and audits where warranted — we're ready for the initial mainnet launch and deployment.

05

Ongoing support

We stand with our development partners after launch, providing monitoring, maintenance, and ongoing support for the products we create.

Permissionless vs. permissioned blockchains.

Public, open chains and private, permissioned ledgers solve different problems. We help you pick the right model — and build either.

Public / permissionlessPrivate / permissioned
Who can participateAnyone — open validators and usersKnown, vetted participants only
Example platformsEthereum, Polygon, Solana, BaseHyperledger Fabric, consortium chains
ConsensusProof-of-stake / proof-of-workPluggable (e.g., Raft, BFT) with known validators
TransparencyFully public, censorship-resistantConfidential, controlled visibility
Throughput & costGas fees; scaled via Layer-2 rollupsHigh throughput, low/no per-tx fees
Best forDeFi, NFTs, open composabilityEnterprise consortia, regulated data

Platforms & technologies we build on.

Our blockchain developers are fluent across the modern Web3 stack — Layer-1s, Layer-2s, languages, and the off-chain infrastructure that makes dApps usable.

Layer-1

Ethereum & EVM

The most composable smart-contract ecosystem — Solidity, the EVM, and the deepest DeFi and NFT tooling.

Layer-2

Polygon · Arbitrum · Base

EVM-compatible rollups and sidechains that cut gas costs and scale throughput without leaving the Ethereum ecosystem.

High throughput

Solana

Low-fee, high-speed chain (Rust) for consumer-scale apps, payments, and on-chain marketplaces.

Enterprise

Hyperledger Fabric

Permissioned, modular ledger for consortia that need privacy, known validators, and compliance controls.

Oracles

Chainlink

Bring real-world data and verifiable randomness on-chain — price feeds, automation, and cross-chain messaging.

Indexing

The Graph

Query on-chain data efficiently with subgraphs so your dApp frontend stays fast and responsive.

Storage

IPFS & Arweave

Decentralized, content-addressed storage for NFT metadata, media, and documents.

Tooling

Foundry & Hardhat

Modern development, testing, fuzzing, and deployment pipelines for reliable, gas-optimized contracts.

What you get with DEV.co.

  • Senior blockchain developers — engineers who have shipped production smart contracts, dApps, and integrations across EVM and non-EVM chains.
  • Security-first smart contracts — secure patterns, unit and fuzz testing, static analysis, gas optimization, and coordinated third-party audits for high-value protocols.
  • The right chain for the job — honest guidance on public vs. permissioned, Layer-1 vs. Layer-2, and consensus trade-offs before you commit.
  • End-to-end dApp delivery — Web3 frontends, wallet integration, oracles, indexing, and decentralized storage — not just a contract in isolation.
  • Integration with what you run today — blockchain systems connected to your existing infrastructure with clear documentation and zero-downtime cutover.
  • Support after launch — monitoring, maintenance, and a roadmap that evolves with the ecosystem and your needs.

Ways to engage.

From a focused architecture and chain-selection discovery to a full dApp build and ongoing protocol support.

Blockchain Discovery
2–4 weeks
from $12,000
  • Use-case & feasibility review
  • Chain & consensus selection
  • Architecture + tokenomics plan
  • Security & compliance assessment
  • Effort + cost estimate
Start a Discovery
Smart Contract / dApp Build
ongoing
custom
  • Dedicated senior blockchain team
  • Solidity / Vyper / Rust contracts
  • Web3 frontend + wallet integration
  • Oracles, indexing & storage
  • Testnet → mainnet deployment
Plan Your Build
Audit & Optimization
project
custom
  • Smart contract security review
  • Static analysis + fuzz testing
  • Gas optimization
  • Third-party audit coordination
  • Remediation & re-test
Request an Audit
The bottom line

With the right ideas and the right blockchain development partner, distributed ledger technology can transform how your industry handles trust, value, and transparency — and DEV.co builds it to production standard.

Blockchain development questions.

What is a smart contract, and what is a dApp?
A smart contract is self-executing code deployed to a blockchain — it runs exactly as written, without an intermediary, when its conditions are met. On Ethereum and other EVM-compatible chains, smart contracts are typically written in Solidity (or Vyper) and compiled to bytecode for the Ethereum Virtual Machine. A dApp (decentralized application) is a full application whose backend logic lives in one or more smart contracts, usually paired with a Web3 frontend (ethers.js or web3.js) and a wallet such as MetaMask. Together, smart contracts and dApps let you move trust from a central server to a transparent, tamper-resistant, distributed ledger.
Which blockchain platform should I choose?
It depends on your use case, throughput needs, cost tolerance, and whether you want a public (permissionless) or private (permissioned) network. Ethereum and EVM-compatible Layer-2s (Polygon, Arbitrum, Optimism, Base) are the default for DeFi, NFTs, and broad composability. Solana suits high-throughput, low-fee consumer apps. Hyperledger Fabric and other permissioned ledgers fit enterprise consortia that need privacy, known validators, and compliance controls. Our blockchain developers help you weigh consensus mechanism, finality, gas/transaction costs, ecosystem tooling, and regulatory exposure before committing — so you don't rearchitect later.
Do you audit and optimize smart contracts?
Yes. Because smart-contract code is immutable once deployed and often custodies real value, security is non-negotiable. We follow secure development patterns (checks-effects-interactions, reentrancy guards, access control), write extensive unit and fuzz tests (Foundry/Hardhat), run static analysis (Slither) and where warranted formal verification, and optimize for gas so transactions stay affordable. For high-value protocols we coordinate independent third-party audits and structure upgradeable proxy patterns and timelocks so issues can be remediated responsibly.
How much does blockchain development cost?
Cost scales with scope. A focused smart-contract build or proof-of-concept is far less involved than a full DeFi protocol or a production dApp with wallet integration, indexing, oracles, and a third-party audit. We typically start with a paid discovery to define the architecture, chain selection, and scope, then estimate the build from there. Engaging experienced blockchain developers up front usually lowers total cost — bugs caught in design are dramatically cheaper than vulnerabilities discovered after a contract is live on-chain.
What will I get partnering with DEV.co?
DEV.co provides end-to-end blockchain consulting and development: custom applications, smart contract design and development, decentralized applications (dApps), DeFi and tokenization work, Web3 and wallet integration, and the integration of new blockchain systems into your existing infrastructure. You get senior engineers who have shipped production distributed-ledger software, a collaborative process from scope through launch, and ongoing support after deployment.
How can I become a blockchain developer?
There are many paths into blockchain development — from online courses and bootcamps to traditional brick-and-mortar computer-science programs. Beyond general software engineering, you'll want a working understanding of cryptographic hash functions, public-key cryptography, consensus mechanisms, and how blocks, transactions, and state work on a chain. From there, learning Solidity and the EVM (or Rust for Solana) plus tooling like Hardhat, Foundry, and ethers.js opens the door to building smart contracts and dApps. Demand for qualified blockchain developers remains strong, so the skills tend to be well rewarded.
What is the future of blockchain developers — and the salary outlook?
Demand for blockchain developers continues to grow as more industries adopt distributed ledger technology. In the United States, blockchain developers earn roughly $98,000 per year on average; in markets like Singapore the average runs closer to $140,000. Entry-level roles commonly start in the $50,000–$70,000 range. Because qualified talent is in relatively short supply and the technology keeps expanding into finance, supply chain, healthcare, and public records, salaries for skilled blockchain developers have tended to rise faster than the broader software market.

Partner with DEV.co on your blockchain project.

Whether you need a single audited smart contract, a full decentralized application, or guidance on which chain to build on, our blockchain developers can help. Tell us what you're building — we'll map a secure path from scope to mainnet.