SeaBridge — Cross-Border Payments via Telegram

The Problem

For migrant workers: Traditional remittance services charge 6–8% per transfer, with fees hidden inside exchange rates. A worker sending Rp 5 juta home loses Rp 300–400 ribu every month to fees.

For recipients: Crypto-based solutions require the recipient to download a new app, understand wallets, and convert tokens to cash. Most families receiving remittances don't want to do this.

For everyone: Telegram has ~90% penetration in Indonesia. The interface already exists. The friction is in the payment layer.

What SeaBridge Does

SeaBridge is a Telegram bot built on Stellar that handles the full remittance flow:

1. Worker tops up balance via Indonesian bank transfer (Xendit on-ramp)
2. Worker sends to recipient using a /send command with guided step-by-step flow
3. Stellar handles the cross-border conversion (IDR → VND, PHP, etc.) via SDEX
4. Recipient's money arrives in their bank account or GoPay/OVO (Xendit off-ramp)

The recipient never touches crypto.

Supported Corridors

From	To	Stablecoin
Indonesia	Vietnam	IDR → IDRX → VNDT
Indonesia	Philippines	IDR → IDRX → PHPC
Philippines	Indonesia	PHP → PHPC → IDRX

Key Features

Transparent Pricing — Exchange rate and total fee are shown before PIN confirmation. No surprises.

QRIS Payments — Scan a QRIS merchant QR code from the bot, pay from IDR balance. Works cross-border.

Bilingual — Full Indonesian and English interface, switchable from /settings.

Non-Custodial Option — Users can export their Stellar private key at any time.

Mobile-Native UX — Inline keyboard buttons instead of typed commands. Feels like an app.

Stellar Integration

SeaBridge uses the full SEP protocol stack:

• SEP-10 — Wallet authentication
• SEP-24 — Interactive on/off-ramp (fiat ↔ stablecoin via anchors)
• SEP-31 — Cross-border payment routing
• SDEX — Stellar DEX for real-time FX between IDRX, VNDT, and PHPC

Bot Commands

Command	Description
/start	Home dashboard with balance
/register	Create account with phone + PIN
/send	Guided send money flow
/pay	QRIS merchant payment
/history	Paginated transaction history
/topup	Top-up via bank transfer
/withdraw	Withdraw to bank/e-wallet
/settings	PIN, language, export key

Security

• PIN encrypted with bcrypt
• Stellar private keys encrypted with AES-256-GCM + PBKDF2 key derivation
• Session state managed per Telegram user ID
• JWT for internal API authentication

Built For

SEA Stellar Hackathon — Rise In 2026 — targeting the cross-border payments and financial inclusion track.