Blockchain Exchange Backend Developer (Remote Freelance Position)

Position Overview

• Job Type: Project-based freelance
• Location: Fully remote (global)
• Daily Rate: $700 (estimated)
• Project Duration: 15 days
• Total Budget: $10,500

Core Requirements

👉 Experienced blockchain wallet developers with Java Spring framework expertise are strongly encouraged to apply.

Technical Responsibilities

1. Wallet Modification System

• Implement cross-chain deposit/withdrawal support for:

  • Major Chains: BTC, ETH (ERC20), BCH, LTC, EOS (account model), TRX (TRC20), BNB (BEP20)

  • Key Features:

    • Replace third-party UDUN API with self-hosted RPC interfaces
    • Configurable withdrawal fees (percentage or fixed)
    • Token management system for chain-specific assets

• Required technologies:

  • JSON-RPC clients
  • Web3J integration

2. Enhanced Security Features

• Google Authenticator integration for:

  • Withdrawal verification (selectable between SMS/email/Google Auth)
  • Admin-controlled unbinding/re-binding functionality

• Example implementation reference:

  "Users must pass one verification method (SMS/Google Auth/email) to authorize withdrawals."

3. Multi-Method Registration System

• Flexible signup options:

  • Phone number (SMS-gated)
  • Email registration

  • MetaMask login with mandatory:

    • Email binding
    • 2FA setup

• Critical requirement:

  "MetaMask-authenticated users must complete profile binding before system access."

Exchange Management Features

4. C2C Exchange Configuration

• Dual-mode pricing:

  • API-based market rates
  • Manual override capability

• Implementation guide:

  Global API Documentation: [Gate.io API V4 Reference](https://www.gateio.ch/docs/developers/apiv4/zh_CN/)

5. Instant Swap Functionality

• Dynamic pricing engine for:

  • Cross-pair arbitrage (e.g., BTC/USDT → BCH/USDT)

  • Configurable parameters:

    Feature	Setting
    Time Window	30-60 seconds
    Rate Calculation	Real-time or fixed
    UI Status Display	On/off toggle

6. Crypto Investment Products

1. Administration Panel:

   • Master enable/switch
   • Asset management (add/remove)

2. Product Rules:

   • Flexible term periods
   • APR configuration
   • Daily yield distribution
   • Automatic maturity release

Partnership Program Features

7. Multi-Level Partner System

• Tier Structure:

  Level	Requirements	Benefits
  LV1	500+ referrals	Base rewards
  LV2	1,500+ referrals	Enhanced splits
  LV3	3,000+ referrals	Premium status

• Upgrade Paths:

  • Referral milestones OR
  • Trading volume thresholds ($2M/$4M/$6M)

8. Revenue Sharing Model

• Profit sources:

  • Trading fee rebates
  • Token airdrops
  • Platform token dividends

• Key feature:

  "Trading mining rewards convert activity into platform tokens with utility value."

Administrative Controls

9. Market Management

• Dynamic trading pair configuration
• Regional availability controls

10. CTC Management Suite

1. Liquidity Providers:

   • CRUD operations

2. Order Processing:

   • Audit trails
   • Permission-based actions

FAQ Section

Q1: What blockchain experience is mandatory?

A: Candidates must have deployed wallet solutions supporting at least two major chains (BTC/ETH required).

Q2: How flexible is the remote work arrangement?

A: This is 100% remote with asynchronous coordination - no timezone restrictions.

Q3: What Spring modules are most used?

A: Spring Boot, Security, and Data are core to this implementation.

Q4: Can partners combine referral and volume qualifications?

A: Yes - thresholds are independent and upgrades apply on first qualification.

Q5: What's the timeline for API replacement?

A: Phase 1 (wallet RPC) must complete within 7 days post-start.

👉 See live implementation examples for technical reference.