# Install Dependencies - PostgreSQL

Next we will install all packages that we will require for the backend when working with PostgreSQL data store. If you want to work with MongoDB go [here](https://arif-hanif.gitbook.io/slackclone/server/getting-started/install-dependencies-mongo). We will build up the use of each but will install all of them in the project now.

```aspnet
dotnet add package HotChocolate
dotnet add package HotChocolate.AspNetCore
dotnet add package HotChocolate.AspNetCore.Playground
dotnet add package HotChocolate.AspNetCore.Subscriptions
dotnet add package HotChocolate.Subscriptions.InMemory
dotnet add package HotChocolate.Types
dotnet add package HotChocolate.Types.Filters
dotnet add package HotChocolate.Types.Sorting

dotnet add package Microsoft.EntityFrameworkCore
dotnet add package Microsoft.EntityFrameworkCore.Tools
dotnet add package Microsoft.EntityFrameworkCore.Design
dotnet add package Npgsql.EntityFrameworkCore.PostgreSQL

dotnet restore
```

The `HotChocolate.AspNetCore` package contains the ASP.NET core middle-ware for hot chocolate and also includes the Hot Chocolate query engine as a dependency.

The `HotChocolate.AspNetCore.Playground` package adds the [GraphQL Playground](https://github.com/prisma-labs/graphql-playground) IDE.

The `HotChocolate.AspNetCore.Subcriptions` package adds the capabilities to do subscriptions with the `HotChocolate.Subscriptions.InMemory` adding for it be in memory. Visit  [hotchocolate.io](https://hotchocolate.io) for using additional backends for subscriptions.

The `HotChocolate.Types.Filters`package adds the capabilities to do filtering on fields.

The `HotChocolate.Types.Sorting` package adds the capabilities to do sorting on fields.

The remainder of the packages add Entity Framework Core and the Npgsql driver for PostgreSQL.