Crypto-to-fiat accounting automation platform that provides real-time price oracles, automated USD conversion tracking, and generates compliant financial reports for crypto-enabled businesses.

Repository: SubStream-Protocol/SubStream-Protocol-Backend Author: elizabetheonoja-art Description: This issue bridges the gap between strictly crypto-denominated on-chain payments and fiat-denominated SaaS accounting. Currently, when a user is billed 50 USDC or 500 XLM, the backend does not know the exact USD equivalent at that moment. We need to build a cron job that periodically fetches historical exchange rates using the SEP-40 Oracle standard. The service must run every 5 minutes and store the exact asset_to_usd exchange rate in a PriceCache table. When the event indexer processes a SubscriptionBilled event, it must instantly query this price cache. It must append the usd_equivalent_value to the BillingEvent record before saving it to the database. The core logic is essential for generating accurate B2B tax receipts and calculating true Monthly Recurring Revenue (MRR). Ensure the service handles rate limits from the external pricing API by implementing a robust backoff strategy. If the price cache is completely unavailable, the billing event should be saved with a null USD value and flagged for backfilling. Write tests validating the chronological matching logic (finding the price closest to the ledger timestamp). Acceptance 1: Every billing event is accurately tagged with its real-world fiat equivalent at the time of execution. Acceptance 2: The pricing cron job is resilient to network failures and upstream Oracle downtime. Acceptance 3: The backend can generate accurate, fiat-denominated financial reports for enterprise merchants. Labels: data, oracle, finance