**Tags:** "Hello World" Examples · .NET # .NET Hello world [.NET 9](https://dotnet.microsoft.com/) recipe for [Zerops](https://zerops.io) demonstrating a minimal web service with automatic PostgreSQL migrations and a health check endpoint that verifies live database connectivity. Includes ready-made configurations for every stage of the development lifecycle — from AI agent environments to highly-available production. ### Available Environments - [AI Agent](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=ai-agent) - [Remote (CDE)](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=remote-cde) - [Local](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=local) - [Stage](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=stage) - **Small Production** ← current - [Highly-available Production](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=highly-available-production) ### Services in this Environment **Services:** - **core** (core:single@2) - Containers: 1 × Shared Core, 0.00 GB RAM, 0 GB Disk - **app** (ubuntu/dotnet@9) :8080 - Containers: 2 × Shared Core, 0.75 GB RAM, 1 GB Disk - Repository: [zerops-recipe-apps/dotnet-hello-world-app](https://github.com/zerops-recipe-apps/dotnet-hello-world-app) - **db** (postgresql:single@16) :5432, :6432 - Containers: 1 × Shared Core, 4.50 GB RAM, 1 GB Disk **Total Resources:** 4 containers, 6.00 GB RAM, 3 GB Disk ### One-Click Deploy (Import YAML) Use this YAML with `zcli project import` to deploy this environment: ```yaml # Small production environment offers a production-ready setup # optimized for moderate throughput. project: name: dotnet-hello-world-small-prod services: # Production app — compiled and deployed using the 'prod' # zeropsSetup. Zerops builds framework-dependent .NET artifacts # and runs the readiness check (GET /) before routing traffic. # minContainers: 2 keeps two replicas running at all times for # availability and horizontal load distribution. Zerops scales # RAM automatically within the verticalAutoscaling bounds. # minFreeRamGB: 0.25 reserves headroom for the .NET runtime's # GC cycles and traffic spikes — without it, the container hits # the minRam ceiling and gets OOM-killed under load. - hostname: app type: dotnet@9 zeropsSetup: prod buildFromGit: https://github.com/zerops-recipe-apps/dotnet-hello-world-app enableSubdomainAccess: true minContainers: 2 verticalAutoscaling: minRam: 0.5 minFreeRamGB: 0.25 # PostgreSQL single-node for moderate production traffic. # Automatic encrypted backups are on by default. For # higher-durability requirements, consider HA mode or # your own backup strategy. # Priority 10 starts the database before app containers. - hostname: db type: postgresql:single@16 profile: oltp-production priority: 10 ``` --- ## Next Steps After deploying one of the environments and getting to know Zerops, you have two paths to choose from: 1. **Template Flow** — Clone our GitHub repositories and use the whole recipe as a template 2. **Integrate Flow** — If you already have an existing application on a similar stack, integrate the recipe setup with your application Select a flow: [Template Flow](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=small-production&guideFlow=template) or [Integrate Flow](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=small-production&guideFlow=integrate) Both flows are shown below: ## How to take over the Small Production environment ### 📦 Clone the template repositories Fork or clone the following repositories to your local machine or GitHub account: - [zerops-recipe-apps/dotnet-hello-world-app](https://github.com/zerops-recipe-apps/dotnet-hello-world-app) ### 1. Find your service name Many commands and configurations need the exact name of your service. You can find it in the Zerops Dashboard. - Open your project in the Zerops Dashboard. - In the project overview, find the service you want to manage. - Use this exact name whenever a command or pipeline configuration asks for ``. Zerops GUI: Locating the Service Name ### 2. Configure deployment pipeline Go to Service Settings > Pipelines & CI/CD Settings in the Zerops Dashboard and connect your repository. For production, use a trigger on new tags. This keeps deployments intentional and tied to a specific version. You can also add a regex filter, such as `^v[0-9]+\.[0-9]+\.[0-9]+$`, if you want to allow only semantic version tags. Zerops GUI: Triggers Alternatively, add `zcli push` to your existing CI/CD pipeline if you want full control over when deployments happen. Learn more about pipeline triggers: https://docs.zerops.io/features/pipeline ### 3. Deploy to production Create and push a new Git tag to deploy a specific version of your app: ```bash git tag -a v1.0.0 -m "Release version 1.0.0" git push origin v1.0.0 ``` > [!TIP] > Open the pipeline detail in the Zerops Dashboard to check the build progress and verify that all steps finish successfully. ### 4. Configure autoscaling Review the autoscaling settings for your runtime services and databases in Service Settings > Automatic Scaling Configuration in the Zerops Dashboard. Zerops GUI: Autoscaling configuration The most important settings are: ```yaml verticalAutoscaling: minRam: 1 minFreeRamGB: 0.5 minFreeRamPercent: 20 ``` > [!CAUTION] > Pay attention to `minFreeRamGB`. This value tells Zerops when to scale RAM vertically. Adjust it based on your app’s real memory needs. RAM scales up immediately, while CPU scales after two consecutive measurements below the threshold. > [!TIP] > Run a quick stress test with a tool like hey before real users arrive. This helps you see how your app behaves under load and tune the autoscaling settings. ### 5. Set up your domain To send real traffic to your app, configure public HTTP access in Service Settings > Public Access & Internal Ports in the Zerops Dashboard. Add your custom domain and point your DNS records to the Zerops IPs shown in the dashboard: Zerops GUI: Public access and custom domain ```text Type Name Content TTL A example.com Auto AAAA example.com Auto ``` For wildcard domains, add a CNAME record for SSL validation. Check the public access documentation: https://docs.zerops.io/features/access > [!TIP] > When changing DNS records for production, start with a low TTL value. Make sure SSL certificates are active before you disable the fallback Zerops subdomain. Once everything works, you can disable the Zerops subdomain so all traffic goes through your custom domain. --- ### 🎉 You are good to go! Your application is live in production and the core setup is complete. The following sections are optional. They cover extra production features such as log forwarding, backups, and diagnostic access. You can stop here and come back later when you need them. --- ### 6. Set up log forwarding (Optional) To send logs to an external service, go to Project Settings > Log Forwarding & Logs Overview in the Zerops Dashboard. You can forward logs to services like Better Stack, Papertrail, or your own self-hosted solution. Learn more about log forwarding: https://docs.zerops.io/references/logging ### 7. Configure database backups (Optional) Manage automated encrypted backups in Service Settings > Backups in the Zerops Dashboard. By default, backups run daily between 00:00 and 01:00 UTC. Before a major deployment, create a manual protected backup: ```bash zcli backup create --tags pre-deploy,protected ``` Read the backup documentation for more options: https://docs.zerops.io/features/backup ### 8. Set up diagnostic access (Optional) Use zCLI and VPN access when you need to inspect or maintain services directly. For runtime services: ```bash zcli vpn up ssh .zerops ``` For databases, connect through the VPN to reach the project’s private network, or set up secure direct IP access for your database admin tools. Check the VPN documentation: https://docs.zerops.io/references/cli/commands#vpn-up ## How to integrate app with Zerops ### 1. Adding `zerops.yaml` The main application configuration file you place at the root of your repository. It tells Zerops how to build, deploy, and run your application. ```yaml zerops: # Production setup — compile both app and migration, deploy # minimal framework-dependent artifacts to the runtime container. - setup: prod build: base: dotnet@9 buildCommands: # Publish framework-dependent artifacts (runtime provided by # the dotnet@9 container image — no bundled runtime needed). # dotnet publish implicitly restores NuGet packages first. - dotnet publish App/App.csproj -c Release -o out/app - dotnet publish Migrate/Migrate.csproj -c Release -o out/migrate # Deploy only the published output — no source, no obj/ dirs. deployFiles: - ./out # cache: true snapshots the global NuGet package cache # (~/.nuget/packages) in the build container image, so # subsequent builds skip re-downloading packages. cache: true # Readiness check: verifies new containers respond before the # project balancer routes traffic to them (zero-downtime deploy). deploy: readinessCheck: httpGet: port: 8080 path: / run: base: dotnet@9 # Run the migration exactly once per deploy version across all # containers. initCommands runs before start on every container # — zsc execOnce ensures only one container executes, all others # wait. Placed in initCommands (not buildCommands) so schema # changes deploy atomically with the new application code. initCommands: - zsc execOnce ${appVersionId} --retryUntilSuccessful -- dotnet ./out/migrate/Migrate.dll ports: - port: 8080 httpSupport: true envVariables: ASPNETCORE_ENVIRONMENT: Production # Kestrel listens on all interfaces at port 8080. ASPNETCORE_URLS: http://0.0.0.0:8080 # Referencing variables — Zerops injects credentials for the # 'db' service using the pattern {hostname}_{credential}. DB_NAME: db DB_HOST: ${db_hostname} DB_PORT: ${db_port} DB_USER: ${db_user} DB_PASS: ${db_password} start: dotnet ./out/app/App.dll # Development setup — deploy full source code so the developer can # SSH in and run the app interactively. NuGet packages are restored # in the build container to populate the cache; the developer runs # 'dotnet restore' again after SSH (runtime container starts fresh). - setup: dev build: base: dotnet@9 buildCommands: # Restore packages to populate the NuGet cache in the build # container (cached via cache: true for subsequent builds). # The developer will need to run 'dotnet restore' after SSH — # NuGet cache lives in the build container, not the runtime. - dotnet restore App/App.csproj - dotnet restore Migrate/Migrate.csproj # Deploy the entire working directory — source code, project # files, and zerops.yaml (so 'zcli push' works from SSH). deployFiles: ./ cache: true run: base: dotnet@9 # Migration still runs on deploy — database is ready when the # developer SSHs in. Compiles Migrate on the fly via 'dotnet # run'; zsc execOnce ensures single execution per version. initCommands: - zsc execOnce ${appVersionId} --retryUntilSuccessful -- dotnet run --project Migrate/Migrate.csproj ports: - port: 8080 httpSupport: true envVariables: ASPNETCORE_ENVIRONMENT: Development ASPNETCORE_URLS: http://0.0.0.0:8080 # HOME is required — .NET CLI and NuGet use it to locate # package caches and temp dirs in the runtime container. HOME: /home/zerops DB_NAME: db DB_HOST: ${db_hostname} DB_PORT: ${db_port} DB_USER: ${db_user} DB_PASS: ${db_password} # Container stays idle — developer starts the app via SSH: # dotnet restore App/App.csproj # dotnet run --project App/App.csproj start: zsc noop --silent ``` ### 🎯 What's next? **Deploy other environments** — Ready to scale? Deploy additional environments for different stages of your workflow: - [AI Agent](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=ai-agent) - [Remote (CDE)](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=remote-cde) - [Local](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=local) - [Stage](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=stage) - [Highly-available Production](https://app.zerops.io/recipes/dotnet-hello-world.md?environment=highly-available-production) ## Knowledge Base ### Platform Reference - [Routing & Domains](https://docs.zerops.io/features/access) - [Scaling](https://docs.zerops.io/features/scaling) - [Environment Variables](https://docs.zerops.io/features/env-variables) - [CLI (zcli)](https://docs.zerops.io/references/cli) ### Service Type Reference **.NET** - [Build & Deploy](https://docs.zerops.io/dotnet/how-to/build-pipeline) - [Customize Runtime](https://docs.zerops.io/dotnet/how-to/customize-runtime) **PostgreSQL** - [Connect](https://docs.zerops.io/postgresql/how-to/connect) - [Backup & Restore](https://docs.zerops.io/postgresql/how-to/backup) - [Manage](https://docs.zerops.io/postgresql/how-to/manage) - [Scale](https://docs.zerops.io/postgresql/how-to/scale) --- ## Related Recipes - [Bun Hello World](https://app.zerops.io/recipes/bun-hello-world.md) - [Go Hello World](https://app.zerops.io/recipes/go-hello-world.md) - [Zerops showcase](https://app.zerops.io/recipes/zerops-showcase.md) - [Java Hello World](https://app.zerops.io/recipes/java-hello-world.md)