Observability first

Why it matters

Enterprise systems live or die on the details. Here is a small example of the kind of guard clause that keeps a payment flow honest.

def apply_discount(total, percent):
    if not 0 <= percent <= 100:
        raise ValueError("percent must be between 0 and 100")
    return round(total * (1 - percent / 100), 2)

We treat every edge case as a first-class citizen, because in production, they are.

What we shipped

• Idempotent APIs that survive retries
• Observability baked in from day one
• A migration path that never needs a big-bang cutover