Getting started with Aspire nightly and Dev Containers

Build apps with JavaScript/TypeScript, Python, .NET, or a mix of languages using Aspire. This repository provides a ready-to-use development environment for Visual Studio Code Dev Containers and GitHub Codespaces, with nightly Aspire builds and additional tooling for Aspire team dogfooding.

Note

This repository installs the latest daily builds of Aspire. Use microsoft/aspire-devcontainer as a template for the latest released bits. Aspire team members can create a Codespace directly from this repository to take advantage of prebuilds and reduce startup time.

What's included

The container uses an Ubuntu 24.04 base image, with language tooling installed as Dev Container Features:

Tooling	Purpose
Nightly Aspire CLI and Aspire VS Code extension	Dogfood orchestration and debug your app's services
Docker-in-Docker	Run containers for databases, caches, and other dependencies
Node.js LTS and npm	Develop JavaScript and TypeScript apps
Python and uv	Develop Python apps and manage packages and virtual environments
.NET 10 SDK and C# Dev Kit	Develop .NET apps
PowerShell	Run cross-platform automation scripts
Azure CLI, Azure Developer CLI (azd), and Azure/Bicep extensions	Exercise Azure deployment scenarios
kubectl, Helm, Minikube, and the Kubernetes extension	Exercise Kubernetes development and deployment scenarios

VS Code includes JavaScript/TypeScript support, with ESLint, Python, and Pylance extensions installed alongside the existing Aspire, .NET, Azure, Kubernetes, and GitHub Copilot extensions. Codespaces requests 8 CPUs, 32 GB of memory, and 64 GB of storage.

Get started

1. Create a Codespace directly from this repository for team testing, or create a repository from this template.
2. Alternatively, clone the repository and select Dev Containers: Reopen in Container in VS Code. Local development requires Docker and the Dev Containers extension.
3. Run aspire new in the container terminal to choose an app template, or bring your existing services into the repository.

For more guidance, see:

• Aspire and GitHub Codespaces
• Aspire and Visual Studio Code Dev Containers

Customize your environment

Edit .devcontainer/devcontainer.json to change language versions, add tooling, or remove features you don't need. Rebuild the container after changing its configuration. The Dev Container configuration reference describes the available options.

Unlike the released template, this repository installs the Aspire CLI through oncreate.sh using the installer's -q dev option. Installation retries transient failures, then clears NuGet caches when the standalone SDK is present to keep Codespaces prebuilds small. The hook runs during creation/prebuild, not every restart. The Dockerfile supplies ICU for the CLI even without a standalone .NET SDK, and the remote environment puts the nightly CLI on PATH for terminals and lifecycle commands.

The template does not run an application-specific restore command. Install your app's dependencies with its package manager, such as npm install, uv sync, or dotnet restore. The repository's nuget.config retains NuGet.org and the dotnet10 feed for team testing.

The container configures HTTPS development certificates at startup through Aspire, independent of your app's language:

aspire certs trust --non-interactive

Aspire stores these certificates under ~/.aspnet/dev-certs/trust. The container's remote environment includes this directory in SSL_CERT_DIR so OpenSSL-based tools such as curl can verify HTTPS endpoints from the container terminal.

Trust inside the container does not automatically make your host browser trust the certificate. Follow the Dev Containers HTTPS guidance for local browser setup.

Note

Once you have created your repository from this template please remember to review the included files such as LICENSE, CODE_OF_CONDUCT.md, SECURITY.md and this README.md file to ensure they are appropriate for your circumstances.

CI checks

The Devcontainer workflow runs on pull requests, pushes to main, and manual dispatch. Each matrix job starts the actual nightly devcontainer and runs smoke checks before and after stopping and reopening it:

Scenario	AppHost and services
Python and React	TypeScript AppHost, FastAPI, React, and Redis; also compiles a .NET console app
C# and Blazor	C# AppHost, ASP.NET Core API, Blazor, and Redis
TypeScript without .NET SDK	TypeScript AppHost, Express, and React, with the standalone .NET SDK feature omitted

All jobs check non-root workspace access, language and team CLI tooling, startup certificate trust, Docker-in-Docker, and app endpoints. HTTPS requests verify certificates normally. The SDK-free job checks that dotnet is absent from PATH before and after running Aspire; Aspire still manages its own bundled .NET components. This is a test-only configuration, not a separate editor preset.

Sample projects stay inside the container, with a copy of the repository's NuGet configuration in their parent directory so restores inherit the team feeds. The Redis check uses a non-expiring sentinel value rather than timing-dependent response comparisons. Failures preserve container, AppHost, and resource logs as workflow artifacts. VS Code extensions, debugging, browser rendering, IDE port forwarding, and actual Azure/Kubernetes deployments are not covered.

To run the same checks locally with Docker running:

npx --yes --package @devcontainers/cli@0.89.0 devcontainer up --workspace-folder . --mount-workspace-git-root false --no-lockfile
npx --yes --package @devcontainers/cli@0.89.0 devcontainer exec --workspace-folder . node .github/scripts/smoke-test.mjs

The default scenario is python; append csharp to the smoke command for the C# AppHost. For the SDK-free scenario, generate a temporary configuration with node .github/scripts/prepare-config.mjs --output /tmp/aspire-nightly-no-dotnet/devcontainer.json --without-dotnet, pass --config /tmp/aspire-nightly-no-dotnet/devcontainer.json to both CLI commands, and append typescript-no-dotnet to the smoke command. The helper preserves the Dockerfile and build context paths when relocating the configuration.

To check restart behavior, stop the container identified by the up output, then run both commands again. The smoke script stops its Aspire app; the devcontainer remains running for further use.

Code of Conduct

This project has adopted the code of conduct defined by the Contributor Covenant to clarify expected behavior in our community.

For more information, see the .NET Foundation Code of Conduct.