# Moving from 1.x

> What changed in STX.Sdk 2.0, and how to move an app across.

Source: https://docs.stxapp.io/sdks/csharp/migrating-from-1x/

STX.Sdk 2.0 is a new SDK over the REST API and the WebSocket channels, authenticated with an API key. Nothing from 1.x carries across unchanged, so plan the move as a rewrite of the code that talks to the exchange. 1.x stays installable; to stay on it, pin the range: `<PackageReference Include="STX.Sdk" Version="[1.6.2,2.0)" />`.

| 1.x | 2.0 |
|---|---|
| Email and password login, sessions, token refresh | An API key: every request is signed. See [Authentication](/sdks/csharp/authentication/) |
| `ConfigureSTXServices()` and services resolved from DI | One `STXClient` per exchange; register it as a singleton if you use DI |
| `STXMarketService`, `STXOrderService`, `STXTradeService`, `STXSettlementService` | Methods on `STXClient`: `GetMarketsAsync`, `PlaceOrderAsync`, `GetFillsAsync`, `GetSettlementsAsync` |
| Channel classes and channel wrappers, one socket each | One `STXWebSocket` for every channel; `OrdersAsync`, `FillsAsync`, `PositionsAsync`, `BalancesAsync`, `AccountViewAsync` |
| `decimal` and `double` amounts, enums | Decimal strings exactly as the API sends them; statuses and actions as strings |
| `STXEnvironment.OntarioDemo` and friends | `Region` and `Environment` options, or a credentials profile. See [Environments](/sdks/csharp/environments/) |
| .NET 8 and .NET 10 | .NET 10 |

Cancel-on-disconnect works as before: arm it on the `orders` channel and opt each order in. See [Cancel-on-disconnect](/sdks/csharp/trading#cancel-on-disconnect).

Response models are generated from the [REST API reference](/api/rest/), so their fields follow the API: `market.MarketId`, `order.ClientOrderId`, `position.NetPosition`.