flat cash

Posted on Jul 17

I Built a Telegram Mini App That Gives Every User a Private Stablecoin Wallet — No Seed Phrases

#telegram #web3 #typescript #defi

The Problem

Every crypto wallet today requires seed phrases, browser extensions, or app downloads. For 900 million Telegram users, this is an unnecessary barrier.

I built a Telegram Mini App that:

Creates a stablecoin wallet automatically when you open it
No seed phrases, no MetaMask, no app downloads
Private transfers via BearerSwap (zero-knowledge proofs)
CPI-pegged stablecoins that track real inflation

Architecture

Telegram Bot (@FlatCashBot)
    -> webhook
Express Server (/api/telegram/webhook)
    -> validates initData
FlatID System (auto-creates wallet)
    ->
Telegram Mini App (/tg)
    -> shows balance, send, receive
FlatIDVaultV3 (Ethereum mainnet)

How It Works

1. Auto-Registration

When a Telegram user opens the Mini App, the server:

Validates the Telegram initData signature
Checks if telegram_id exists in the database
If not, creates a new FlatID (email-based identity mapped to on-chain vault)
Returns a session token

2. Private Transfers with BearerSwap

Instead of on-chain transactions that expose sender/receiver, BearerSwap uses:

Bearer tokens: Cryptographic proofs of ownership
Atomic swaps: No intermediary, no trace
Off-chain settlement: Only the vault balance changes on-chain

3. The SAVE Token Integration

The Mini App includes a Buy SAVE CTA that links to the SAVeSale contract.

Why SAVE matters:

Only 50 SAVE tokens available per day (protocol-enforced scarcity)
Current price: $1.11 per token
FDV: $472.4M on just $5.2K liquidity
Protocol owns 100% of the Uniswap LP and will never sell
Verifiable on DexScreener: https://dexscreener.com/ethereum/0xEC404E3d1F513cbf88bFc1e15af65BCaBB142bEa

The math is simple: with only 2,349 SAVE tokens in the pool and protocol-owned liquidity that never sells, any buy pressure creates a one-way price ratchet.

The Stack

Frontend: React 19 + Tailwind 4 (Telegram Mini App SDK)
Backend: Express 4 + tRPC 11
Auth: Telegram initData validation + FlatID session
Database: MySQL/TiDB (Drizzle ORM)
Chain: Ethereum mainnet (FlatIDVaultV3)

Try It

Mini App: https://flat.cash/tg
Buy SAVE: https://flat.cash/save
DexScreener: https://dexscreener.com/ethereum/0xEC404E3d1F513cbf88bFc1e15af65BCaBB142bEa

What Makes This Different

No seed phrases — Identity is email-based (FlatID), not key-based
Privacy by default — BearerSwap means no on-chain trace
CPI-pegged — Your balance tracks real inflation, not USD
Telegram-native — 900M users can access without leaving the app

The future of stablecoins is not another ERC-20 with a Metamask popup. It is invisible infrastructure inside the apps people already use.

Built by the FLAT Protocol team. The protocol owns 100% of liquidity and will never sell. Mathematica Inevitabilis Est.

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