Docs: note Kalshi fixed-point migration

readme

@@ -5,3 +5,33 @@ surrealdb:v2.3.10
 Dokploy  
 ntfy  
 kxbtc15m/bitcoin-price-up-down
+
+## Kalshi API Compatibility Notes (March 2026)
+
+Kalshi migrated API payloads from legacy integer-centric fields to fixed-point fields.
+
+- **March 10, 2026:** fixed-point migration docs updated
+- **March 12, 2026:** legacy integer fields removed from API responses (per migration timeline)
+
+### What changed
+
+Use these fields when parsing order/fill data:
+
+- `fill_count_fp` (string) instead of `fill_count`
+- `taker_fill_cost_dollars` (string dollars) instead of `taker_fill_cost` (cents)
+- `yes_price_dollars` / `no_price_dollars` for price strings
+- similar `_fp` / `_dollars` fields across REST + WebSocket
+
+### Why this matters for Kalbot
+
+If code only reads legacy integer fields, a real fill can be interpreted as zero fill, causing:
+- missing ntfy fill alerts
+- position visible on Kalshi but not tracked correctly in local live state
+
+### Reference docs
+
+- Fixed-Point Migration: https://docs.kalshi.com/getting_started/subpenny_pricing
+- Create Order: https://docs.kalshi.com/api-reference/orders/create-order
+- Get Order: https://docs.kalshi.com/api-reference/orders/get-order
+- User Orders WS: https://docs.kalshi.com/websockets/user-orders
+- User Fills WS: https://docs.kalshi.com/websockets/user-fills