Vertical Slice Template

A .NET 10 API template built around vertical slice architecture and orchestrated with .NET Aspire. The Aspire AppHost wires the API together with its supporting infrastructure — SQL Server, Redis, and Seq — so you can run the whole system locally with a single command.

Solution structure

Project	Description
src/VerticalSliceTemplate.AppHost	Aspire orchestrator and local run entry point. Provisions SQL Server, Redis and Seq containers and launches the API.
src/VerticalSliceTemplate.Api	ASP.NET Core API organized into vertical slices, with API documentation exposed via Scalar.
src/VerticalSliceTemplate.ServiceDefaults	Shared Aspire service defaults (telemetry, health checks, resilience).
tests/VerticalSliceTemplate.Api.Tests	Unit tests.
tests/VerticalSliceTemplate.Api.Integration.Tests	Integration tests.

Prerequisites

• .NET 10 SDK
• A running container runtime — Docker Desktop or a compatible alternative. The AppHost starts SQL Server, Redis, and Seq as containers, so the runtime must be running before you start the app.

First-time setup

Trust the ASP.NET Core development HTTPS certificate (required for the https profile):

dotnet dev-certs https --trust

The SQL Server password is supplied by the sqlPassword parameter, which already has a default value in src/VerticalSliceTemplate.AppHost/appsettings.json. No additional configuration is required to run locally. If you want to override it, set a user secret on the AppHost project:

dotnet user-secrets --project src/VerticalSliceTemplate.AppHost set "Parameters:sqlPassword" "<your-password>"

Running the solution with Aspire (https profile)

From the repository root, run the AppHost using the https launch profile:

dotnet run --project src/VerticalSliceTemplate.AppHost --launch-profile https

This will:

1. Start the SQL Server, Redis, and Seq containers.
2. Start the API.
3. Open the Aspire dashboard at https://localhost:17178.

From the dashboard you can view each resource, its logs, and its endpoints. Open the API's Scalar UI link (served at /scalar on the API's HTTPS endpoint) to explore and call the API.

Using an IDE? Set VerticalSliceTemplate.AppHost as the startup project, select the https launch profile, and start debugging — this is equivalent to the command above.

Running tests

dotnet test

Troubleshooting

• Containers won't start / connection errors: ensure Docker Desktop (or your container runtime) is running before launching the AppHost.
• HTTPS/certificate warnings: run dotnet dev-certs https --trust and restart your browser.
• Persistent containers: SQL Server, Redis, and Seq are configured with a persistent lifetime, so their data survives restarts. Remove the containers manually if you need a clean state.
• Ports in use: the local endpoints use fixed ports (dashboard 17178, Seq 8002, SQL Server 8003, Redis 8004). Free these ports or update the configuration if they conflict with other services.