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---
layout: default
title: How it works
nav_order: 5
---
## How ViewComponent Works
### At application boot
When `ViewComponent::Base` is inherited from, `ViewComponent::Compiler.compile` compiles a component's template(s) into instance method(s) on the component:
```ruby
class MyComponent < ViewComponent::Base
end
```
```erb
<%= Time.now %>
```
Compiles to:
```ruby
class MyComponent < ViewComponent::Base
def _call_my_component
@output_buffer.append = (Time.now)
@output_buffer
end
end
```
### At component instantiation
Component initializer runs if defined. ViewComponent does not perform any actions.
### At render
When a ViewComponent is passed to `render`, Rails calls `render_in`, passing the current [ActionView::Context](https://api.rubyonrails.org/classes/ActionView/Context.html). `ActionView::Context` is used to provide access to the current controller, request, and helpers, which is why they cannot be referenced until a component is rendered.
First, ViewComponent calls the `before_render` method, which gives ViewComponents the opportunity to execute logic before render time but after initialization.
Second, ViewComponent calls `render?`, returning early with an empty string if `render?` returns false.
ViewComponent then renders the component template, wrapped in a call to the `around_render` method.
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