I will build secure cryptocurrency backend apis with multi blockchain support
I Build Scalable SaaS and MVP Apps That Actually Work Flutter, Node, AWS
About this Gig
Expert Server-Side Cryptocurrency Backend Development
Specialized in production-ready cryptocurrency infrastructure with proven multi-blockchain expertise and secure transaction processing.
What You Get:
- Multi-Currency Support: Bitcoin, Litecoin, Dogecoin, Ethereum, 15+ altcoins
- PSBT-Based Signing: Modern transaction signing with client-side security
- Real-Time Processing: Live balance updates via Electrum integration
- Enterprise Security: JWT authentication, rate limiting, input validation
Professional Services:
- RESTful APIs with comprehensive documentation
- Advanced UTXO management and fee optimization
- Custom payment processing with webhook integration
- Optimized database schemas for crypto operations
Security-First:
- Zero private key storage ensures maximum security
- 100% test coverage with 28/28 tests passed
- Industry-standard security practices
- Clean, documented, vulnerability-tested code
Tech Stack: Node.js, Express.js, MongoDB, bitcoinjs-lib, bip32/bip39, WebSocket support
Perfect For: Fintech startups, exchanges, DeFi projects, e-commerce sites, investment platforms
Includes: Complete source code, API testing, security implementation, deployment guide, technical support
My Portfolio
2 reviews for this Gig
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Rating Breakdown
- Seller communication level
- Quality of delivery
- Value of delivery
Sort By
B broke6699

Turkey
Great experience working with Niladri. Strong technical skills, clear communication, and delivered a fully working encrypted E2E flow as expected. Very reliable — looking forward to continuing the collaboration.
$800-$1,000
Price
11 days
Duration
Helpful?B broke6699

Turkey
Niladri delivered a solid end-to-end relayer MVP for our protocol. The architecture was well thought out, especially around the Waku-based intent flow, queue/worker execution, and overall system design. Communication was clear throughout, and he was very responsive to feedback — quickly incorporating...
$600-$800
Price
10 days
Duration
Helpful?
2 reviews for this Gig
| (2) | ||
| (0) | ||
| (0) | ||
| (0) | ||
| (0) |
Rating Breakdown
- Seller communication level
- Quality of delivery
- Value of delivery
Sort By
B broke6699

Turkey
Great experience working with Niladri. Strong technical skills, clear communication, and delivered a fully working encrypted E2E flow as expected. Very reliable — looking forward to continuing the collaboration.
$800-$1,000
Price
11 days
Duration
Helpful?B broke6699

Turkey
Niladri delivered a solid end-to-end relayer MVP for our protocol. The architecture was well thought out, especially around the Waku-based intent flow, queue/worker execution, and overall system design. Communication was clear throughout, and he was very responsive to feedback — quickly incorporating...
$600-$800
Price
10 days
Duration
Helpful?
