# 18.2 Migrate the shop's schema
Since chapter 4, `EnsureSchemaCreatedAsync` has created the shop's tables. It creates what is
missing and changes nothing that exists, which suits a schema that is still being written. A
deployed shop's schema changes under data, so it moves to EF Core migrations. Trax's own tables are
migrated separately, by `UsePostgres` when each process starts, and the two never touch each
other's history.
Add the EF tools, at the version of EF Core the rest of Shopfront uses:
```bash
dotnet tool install dotnet-ef --version 10.0.12
```
`Directory.Packages.props`:
```xml file=Directory.Packages.props
true
true
```
`Microsoft.EntityFrameworkCore.Design` goes in the library that holds the context. `PrivateAssets`
keeps it out of everything that references the library: only the tools use it.
`Shopfront.Core/Shopfront.Core.csproj`:
```xml file=Shopfront.Core/Shopfront.Core.csproj
net10.0
enable
enable
Shopfront
```
The provider options the hub, the tests and the tools use are written once. They put the
migrations' history in the `shop` schema, beside the shop's tables.
`Shopfront.Core/Data/ShopfrontDatabase.cs`:
```csharp compile=app file=Shopfront.Core/Data/ShopfrontDatabase.cs
using Npgsql.EntityFrameworkCore.PostgreSQL.Infrastructure;
namespace Shopfront.Data;
// The provider options the hub, the tests and the EF tools share.
public static class ShopfrontDatabase
{
// The migrations' history goes in the shop's own schema, beside its tables.
public static void Npgsql(NpgsqlDbContextOptionsBuilder npgsql) =>
npgsql.MigrationsHistoryTable("__EFMigrationsHistory", "shop");
}
```
`dotnet ef` builds the context from a design-time factory rather than starting the hub, which
would migrate Trax's tables and run the rest of `Program.cs`.
`Shopfront.Core/Data/ShopfrontDbContextFactory.cs`:
```csharp compile=app file=Shopfront.Core/Data/ShopfrontDbContextFactory.cs
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Design;
namespace Shopfront.Data;
// What dotnet ef builds the context from, instead of starting the hub. It reads the model and
// connects to nothing.
public class ShopfrontDbContextFactory : IDesignTimeDbContextFactory
{
public ShopfrontDbContext CreateDbContext(string[] args) =>
new(
new DbContextOptionsBuilder()
.UseNpgsql("Host=localhost;Database=shopfront", ShopfrontDatabase.Npgsql)
.Options
);
}
```
`Shopfront.Core/Extensions/ShopfrontServiceCollectionExtensions.cs`:
```csharp compile=app file=Shopfront.Core/Extensions/ShopfrontServiceCollectionExtensions.cs
using Microsoft.EntityFrameworkCore;
using Shopfront.Auth;
using Shopfront.Couriers;
using Shopfront.Data;
using Shopfront.Failures;
using Shopfront.Fraud;
using Shopfront.Inventory;
using Shopfront.Payments;
using Shopfront.Staff;
using Shopfront.Suppliers;
using Shopfront.Warehouse;
using Trax.Core.Decisions;
using Trax.Effect.Services.FailureClassifier;
namespace Shopfront.Extensions;
public static class ShopfrontServiceCollectionExtensions
{
// Everything Shopfront's trains need, apart from Trax itself. Every process that runs the
// trains calls it, because Trax checks every train's chain when a process starts.
public static IServiceCollection AddShopfront(
this IServiceCollection services,
string connectionString
) =>
services
// One context per scope, built for that scope's caller: a pool would share it.
.AddDbContextFactory(
options => options.UseNpgsql(connectionString, ShopfrontDatabase.Npgsql),
ServiceLifetime.Scoped
)
.AddScoped(sp =>
sp.GetRequiredService>().CreateDbContext()
)
.AddScoped()
.AddScoped()
.AddSingleton()
.AddSingleton()
.AddSingleton(FraudRules.Live())
.AddSingleton()
.AddSingleton()
.AddSingleton()
.AddSingleton(sp => sp.GetRequiredService())
.AddSingleton()
.AddSingleton();
}
```
Generate the first migration:
```bash
dotnet ef migrations add Initial --project Shopfront.Core --output-dir Data/Migrations
```
```text
Shopfront.Core/Data/Migrations/
├── 20261018214548_Initial.cs
├── 20261018214548_Initial.Designer.cs
└── ShopfrontDbContextModelSnapshot.cs
```
Commit them. Every later change to the model is a migration of its own, `dotnet ef migrations add`
with a name that says what changed.
Your Development database was created by `EnsureSchemaCreatedAsync`, so it has the tables and no
history, and the first migration would fail on tables that already exist. Drop it and let the hub
create it again, or [record the first migration as applied](/docs/effect/move-a-domain-data-context-to-ef-migrations#a-database-ensureschemacreatedasync-already-created).
## SDK Reference
> [Deployment topologies](/docs/reference/deployment-topologies) | [Move a domain data context to EF migrations](/docs/effect/move-a-domain-data-context-to-ef-migrations) | [UseRabbitMq](/docs/sdk-reference/configuration/use-rabbit-mq) | [AddTraxHealthCheck](/docs/sdk-reference/graphql-api/add-trax-health-check) | [Health and liveness](/docs/scheduler/health-and-liveness) | [Startup refusals](/docs/security/startup-refusals) | [UseTraxApiDashboard](/docs/sdk-reference/api-dashboard/use-trax-api-dashboard)
---
Next: [18.3 The hub](/docs/book/deploy/the-hub)