# Mobile Wallet Token (MWT) ATM Backend

> Engineered the mission-critical backend for the Mobile Wallet Token crypto ATM network, allowing users to buy and sell major cryptocurrencies and stablecoins using various fiat currencies. The solution is built on a scalable, high-performance Node.js/Express.js architecture, covering secure blockchain-side logic, API integration with multiple crypto exchanges, and fiat-to-crypto conversion handling.

- **Category:** Blockchain & Web3

## Stack & skills
- Node.js
- Blockchain, NFT & Cryptocurrency
- ExpressJS
- Back-End Development
- AWS Lambda

## Gallery
- Laptop mockup of a navy "Select Operator" kiosk screen; banner text reads ATM APPLICATION and CRYPTO ATM — https://cdn.sanity.io/images/9umagxbl/production/4a162aaace53b11cfdd4f97d27ba9675e85c7282-1000x750.webp
- Kiosk login form with masked Username and Pin fields plus Login, Print Deposit and Print Withdraw buttons on navy — https://cdn.sanity.io/images/9umagxbl/production/bc80edb3b5e4603667e43e3930c3ddb6fa0ff60e-1600x900.webp
- Bilingual welcome screen reading Welcome To Mobile Wallet / Bienvenue, with a photo of a user at an ATM and a Getting Started button — https://cdn.sanity.io/images/9umagxbl/production/3fa9ec699235c4371c8106eba7ad42bb85c02aec-1600x899.webp
- Language chooser headed Select Language/Selectionnez la langue offering English/Anglais and French/francais beside Back and Cancel — https://cdn.sanity.io/images/9umagxbl/production/5942513ee395d38c5c85ecab0280e559565a3b0c-1600x899.webp
- Operator picker listing MoMo from MTN, Orange Money and Crypto tiles on the right, with Back and red Cancel buttons on the left — https://cdn.sanity.io/images/9umagxbl/production/698a9a99d1dc37276ca3042560780c27b40ae5ce-1600x900.webp
- Account-number entry step: a filled input above a blue numeric keypad with Clear All and Backspace keys, plus a Submit button — https://cdn.sanity.io/images/9umagxbl/production/ad6e4cc2c3f3aed3da617263440a85a3dd3c831f-1600x899.webp
- Transaction choice screen asking What would you like to do? with Buy, Sell and Resume options opposite Back and Cancel — https://cdn.sanity.io/images/9umagxbl/production/bf1dd78428732d88f593a099b6fbe502eb536fd8-1600x893.webp
- Cash amount step limited to 5000-200,000 Fcfa, with XAF preset tiles flanking a numeric keypad and an empty amount field — https://cdn.sanity.io/images/9umagxbl/production/53b0b3368d88965a78618d7c42d7a2c992adc5e0-1600x899.webp
- Verify Crypto Rates deposit step prompting for a deposit amount over a numeric keypad, with Next and Submit actions at right — https://cdn.sanity.io/images/9umagxbl/production/43d985367487e4285560f87dc43e40e8b6832d66-1600x899.webp
- One-time-passcode step confirming an OTP was sent to the customer wallet, with a six-digit field, keypad, Submit and Resend OTP — https://cdn.sanity.io/images/9umagxbl/production/8dc4206b058f786c65dd7536040ad872ddef229d-1600x899.webp
- Token picker headed Select Crypto Token listing DAI, SOL, USDC and USDT buttons with coin icons beside Back and Cancel — https://cdn.sanity.io/images/9umagxbl/production/16487111806ffdc25fbabde602517f353593047f-1600x899.webp
- Network selection screen offering BSC and SOL chain buttons on the right, with Back and red Cancel controls on the left — https://cdn.sanity.io/images/9umagxbl/production/1b65e71e492d9024e37f3f19beeb27b5d4bf67d5-1600x899.webp
- Threshold prompt How much do you want to buy/sell? offering Buy above 10,000 XAF and Buy below 10,000 XAF options — https://cdn.sanity.io/images/9umagxbl/production/bff2575e2ff1030f1cc5ef511690e9e6f1a64c45-1600x899.webp

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Canonical page: https://sentientarc.com/portfolio/mwt-crypto-atm-backend