No App Rebuild RequiredHSM Key Storage300+ Wallets Supported
Blockchain Integration · Web2 → Web3
Web3 AddedNon-Disruptive
Wallet auth, crypto payments, NFT gating, and on-chain data integrated into your existing application. No rebuild. No disruption to existing users.
H
A
R
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5★ client satisfaction
YourApp.io
○ Integrating…Existing Stack
Next.jsPostgreSQLStripeREST API← unchanged
No rebuild
Adapter layer only
300+ wallets
WalletConnect v2
No Rebuild
Progressive
HSM Keys
Sign-In with EthereumWalletConnectPrivyDynamicWeb3Authethers.jsviemAWS KMSAlchemyMoralisSIWEEIP-4361Webhook EventsThe GraphTransakMoonPaySign-In with EthereumWalletConnectPrivyDynamicWeb3Authethers.jsviemAWS KMSAlchemyMoralisSIWEEIP-4361Webhook EventsThe GraphTransakMoonPay
2–4 wk
Simple Integration
Wallet auth, token gate
300+
Wallets
Via WalletConnect v2
0
Rebuilds Required
Adapter layer only
6+
Integration Types
Auth, payments, gates…
Integration Types
What we add to your existing app
Each integration is additive — your existing features keep working exactly as before.
Wallet Authentication (SIWE)
Replace or augment traditional login with Sign-In with Ethereum (EIP-4361). No password, no email — users sign a message with MetaMask or any WalletConnect wallet. Works alongside your existing auth flow.
EIP-4361SIWEWalletConnect
Crypto Payments
Accept ETH, USDC, USDT, and custom tokens in your existing checkout. Automatic fiat conversion via on/off-ramp APIs (Transak, MoonPay). Works alongside Stripe — one checkout, both rails.
USDCOn-RampFiat Conversion
NFT-Based Access Control
Gate content, features, or communities behind token ownership. Users holding specific NFTs or ERC-20 tokens get automatic access — no manual approval, no support tickets, no admin overhead.
Token GatingERC-20ERC-721
On-Chain Data Reading
Display wallet balances, token holdings, NFT galleries, and on-chain transaction history inside your existing web app via ethers.js or Alchemy API — without asking users to leave your product.
ethers.jsAlchemyReal-Time
Server-Side Contract Calls
Trigger on-chain functions from your backend — mint tokens, update state, execute business logic — via a secure server-side wallet with HSM key management, nonce tracking, and retry logic.
AWS KMSNonce ManagementBackend
Blockchain Audit Trails
Hash critical records to the blockchain for tamper-evident audit logs. Legal contracts, supply chain events, compliance records, and data provenance — written on-chain and verifiable forever.
Immutable LogsProvenanceCompliance
Integration Failure Patterns
Where blockchain integrations go wrong
Most Web3 integrations fail on UX and security — not the blockchain logic. Every problem below is addressable before you write a line of code.
integration_error.log
ERROR #01
Requiring a Wallet Kills 80% of Users
If your Web3 feature only works for users who already have MetaMask, you've built for 5% of the internet. The other 95% bounce at the wallet connection step — confused, frustrated, and gone. Forcing crypto-native UX on mainstream users isn't progressive — it's a conversion disaster.
Our approach
Progressive Web3: traditional login remains available for all users. Wallet features are offered as an enhancement for those who want them. For crypto-naive users, embedded wallet solutions (Privy, Dynamic, Web3Auth) create wallets with email or social login — no MetaMask required.
Architecture
Bridge Web2 to Web3 without disruption
We add an adapter layer between your existing stack and the blockchain. Your current codebase stays unchanged.
Unchanged
Your Existing App
React / Vue / Next.js
Node.js / Python / Rails
PostgreSQL / MySQL
Stripe / REST APIs
We add this
Integration Layer
Wallet auth adapter
Event webhook handlers
HSM key management
Error recovery + alerting
We connect you here
Blockchain Network
Ethereum / Polygon
Arbitrum / Base / BSC
Smart contracts
On-chain event indexing
What flows through the integration layer
Wallet auth sessions
MetaMaskYour user DB
Crypto payments
ETH/USDCYour orders
NFT gate checks
On-chainYour auth layer
Contract events
BlockchainYour webhooks
Integration Process
Analyze → Design → Deployed
A 4-phase process that ships a secure, monitored blockchain integration without disrupting your existing product.
01
Week 1Requirements Analysis
What blockchain actually adds vs what creates unnecessary complexity. We map the minimal viable integration for your use case and recommend which Web2 features should stay Web2. Deliverable: integration spec with architecture decision rationale.
02
Week 1–2Adapter Design
API contracts, error handling strategy, fallback states, and key management architecture designed before any code is written. Includes: embedded wallet strategy for non-crypto users and monitoring plan for on-chain failures.
03
Week 2–6Integration Development
Backend API endpoints, frontend SDK calls, and smart contract interactions developed and tested against testnet with your existing stack. No framework rewrites — we work with what you have.
04
Week 6–8Hardening & Monitoring
Key management via HSM, transaction monitoring setup, error handling for all blockchain failure modes, and on-call guidance for your team when on-chain issues arise. 30-day post-launch support included.
FAQ
Questions we get all the time
If yours is not here, reach out. We respond within 24 hours with a real answer from an engineer — not a sales pitch.
We build progressive Web3 — traditional login remains available and fully functional. Web3 features are offered as an enhancement, not a gate. For users who want wallet features but don't have MetaMask, embedded wallet solutions (Privy, Dynamic, or Web3Auth) create wallets using email or social login — the user never sees a seed phrase. This approach lets you target Web3-native users and mainstream users simultaneously.
No — that's the whole point. We add an adapter layer that sits between your existing application and the blockchain. Your current codebase, database, and business logic stay unchanged. We add new API endpoints, new frontend components, and new event handlers that extend what you already have. The integration is additive, not disruptive.
Crypto payments bypass the traditional card network entirely, so the crypto-specific payment flow doesn't require PCI DSS compliance. If you accept cards alongside crypto, the card flow still requires PCI compliance independently. On-ramp partners (Transak, MoonPay) handle their own KYC/AML compliance as part of their service.
Simple integrations (wallet auth only, or token gating, or read-only on-chain data) — 2 to 4 weeks. Medium complexity (crypto payments with fiat conversion, server-side contract calls) — 5 to 8 weeks. Complex integrations (audit trail systems, custom event indexing, multi-chain support) — 8 to 14 weeks. We scope precisely in the first call and don't start development until you've approved the spec.
Any EVM-compatible network: Ethereum mainnet, Polygon, Arbitrum, Optimism, Base, BNB Chain, and Avalanche. Solana for high-throughput applications. For most integration use cases, we recommend L2s (Arbitrum, Base, Polygon) due to dramatically lower transaction costs and 1-2 second block times — the difference between a usable and unusable user experience.
Simple integrations — wallet authentication, token gating, or read-only on-chain data — typically run $10K–$25K. Crypto payments with fiat conversion or server-side contract calls land in the $30K–$60K range. Complex work like audit-trail systems, custom event indexing, or multi-chain support runs $60K–$130K. We quote a fixed scope after the spec call, with milestone-based payments and no surprise hourly billing.
We use embedded wallet providers like Privy, Dynamic, or Web3Auth that create a non-custodial wallet from an email or social login — the user never sees a seed phrase. Traditional login stays fully functional, and wallet features are offered as a progressive enhancement. This lets you onboard mainstream users and crypto-native users through the same flow without fragmenting your product.
Yes. We validate every contract interaction on-chain rather than trusting client input, scope token approvals to exact amounts, sign with human-readable EIP-712 typed data, and keep deployer and admin keys behind multi-sig or timelocks. Any custom contracts in the integration go through Slither and Mythril static analysis plus an internal security review before they touch mainnet.
“We needed smart contract work done right — no shortcuts. Their blockchain team audited, optimized, and deployed our DeFi protocol with zero post-launch issues.”
AC
Alex Chen
Founder · Meridian DeFi · Singapore
Ready to IntegrateAdd blockchain to your product
Add blockchain to your product
this quarter
Tell us your existing stack and what blockchain capability you want to add. We'll scope the integration and give you a timeline within 48 hours.
Free consultation24-hour responseNDA on request
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