In the VTEX IO ecosystem, services play a crucial role by allowing you to run .NET and Node.js code directly on VTEX servers. Services enable VTEX IO apps to export HTTP routes, GraphQL resolvers, and event handlers to the server.

To create and export services, you need to specify the node or dotnet builders in your app's manifest.json file. Additionally, GraphQL services can be exported using the graphql builder.

For a practical example, refer to our service example apps: Node.js, .NET, and GraphQL.

For more information, check the Developing services on VTEX IO course in the VTEX Learning Center.

The configuration of your service depends on the selected builder (node or dotnet). You will find the service.json file in the /node or /dotnet folder of your app. This configuration file is responsible for defining essential parameters, including timeout, memory allocation, routes, event handlers, and replicas.

Here's an example of a service.json file:

Let's delve into the parameters you can set within the service.json file:

Name	Type	Description
events	object	Maps a event handler to an object that describes sender or keys.
maxReplicas	number	Defines the maximum number of replicas available.
minReplicas	number	Defines the minimum number of replicas available when the service is running.
memory	number	Allocates the specified memory size (in MB) allocated to the service.
routes	object	Maps route handlers to objects containining information about the route, such as path and public.
timeout	number	Sets the timeout (in seconds) for aborting a connection if a request takes too long.
ttl	number	Defines the time-to-live (in minutes) for how long the platform will keep the service running without receiving new requests (Default: 10 minutes; minimum: 10 minutes; maximum: 60 minutes).
workers	number	Specifies the number of workers to spawn for the service on production. (maximum: 4).

Note that most of these fields are optional, and default values provided by the platform are often sufficient.