Open `docker-dotnet-sample/src/Pages/Index.cshtml` in an IDE or text editor and update the student name text on line 13 from `Student name is` to `Student name:`.

```diff
-    <p>Student Name is @Model.StudentName</p>
+    <p>Student name: @Model.StudentName</p>
```

Save the changes to `Index.cshmtl` and then wait a few seconds for the application to rebuild. Refresh [http://localhost:8080](http://localhost:8080) in your browser and verify that the updated text appears.

Press `ctrl+c` in the terminal to stop your application.

## Create a development container

At this point, when you run your containerized application, it's using the .NET runtime image. While this small image is good for production, it lacks the SDK tools and dependencies you may need when developing. Also, during development, you may not need to run `dotnet publish`. You can use multi-stage builds to build stages for both development and production in the same Dockerfile. For more details, see [Multi-stage builds](/manuals/build/building/multi-stage.md).

Add a new development stage to your Dockerfile and update your `compose.yaml` file to use this stage for local development.

The following is the updated Dockerfile.

```Dockerfile {hl_lines="10-13"}
# syntax=docker/dockerfile:1

FROM --platform=$BUILDPLATFORM mcr.microsoft.com/dotnet/sdk:8.0-alpine AS build
ARG TARGETARCH
COPY . /source
WORKDIR /source/src
RUN --mount=type=cache,id=nuget,target=/root/.nuget/packages \
    dotnet publish -a ${TARGETARCH/amd64/x64} --use-current-runtime --self-contained false -o /app

FROM mcr.microsoft.com/dotnet/sdk:8.0-alpine AS development
COPY . /source
WORKDIR /source/src
CMD dotnet run --no-launch-profile

FROM mcr.microsoft.com/dotnet/aspnet:8.0-alpine AS final
WORKDIR /app
COPY --from=build /app .
ARG UID=10001
RUN adduser \
    --disabled-password \
    --gecos "" \
    --home "/nonexistent" \
    --shell "/sbin/nologin" \
    --no-create-home \
    --uid "${UID}" \
    appuser
USER appuser
ENTRYPOINT ["dotnet", "myWebApp.dll"]
```

The following is the updated `compose.yaml` file.

```yaml {hl_lines=[5,15,16]}
services:
  server:
    build:
      context: .
      target: development
    ports:
      - 8080:8080
    depends_on:
      db:
        condition: service_healthy
    develop:
      watch:
        - action: rebuild
          path: .
    environment:
      - ASPNETCORE_ENVIRONMENT=Development
  db:
    image: postgres
    restart: always
    user: postgres
    secrets:
      - db-password
    volumes:
      - db-data:/var/lib/postgresql/data
    environment:
      - POSTGRES_DB=example
      - POSTGRES_PASSWORD_FILE=/run/secrets/db-password
    expose:
      - 5432
    healthcheck:
      test: ["CMD", "pg_isready"]
      interval: 10s
      timeout: 5s
      retries: 5
volumes:
  db-data:
secrets:
  db-password:
    file: db/password.txt
```

Your containerized application will now use the `mcr.microsoft.com/dotnet/sdk:8.0-alpine` image, which includes development tools like `dotnet test`. Continue to the next section to learn how you can run `dotnet test`.

## Summary

In this section, you took a look at setting up your Compose file to add a local
database and persist data. You also learned how to use Compose Watch to automatically rebuild and run your container when you update your code. And finally, you learned how to create a development container that contains the SDK tools and dependencies needed for development.

Related information:

- [Compose file reference](/reference/compose-file/)
- [Compose file watch](/manuals/compose/how-tos/file-watch.md)
- [Multi-stage builds](/manuals/build/building/multi-stage.md)

## Next steps

In the next section, you'll learn how to run unit tests using Docker.