> ## Documentation Index
> Fetch the complete documentation index at: https://cdktn.io/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Upgrading to CDKTF Version 0.12

> We simplified recursive attribute types to have shorter names

0.12 includes improvements to the provider code bindings, allowing for shorter
attribute names for recursive attributes.

### Simplified interfaces of recursive attributes

The generated provider bindings are based on the Terraform schema which does not
support recursion and hence uses a large, explicit structure instead. Previously
this resulted in long names such as e.g.
`Wafv2WebAclRuleStatementAndStatementStatementOrStatementStatementLabelMatchStatement`.
In 0.12 we implemented a first rough detection for this underlying recursion
which drastically reduced the amount of generated interfaces as they now are
converted to recursive data structures themselves. If you are currently using
those types e.g. in a language like Java, you will need to change them to the
new shorter names.

### `cdktf get` exits with 0 exit code when no provider / module specifications are found in the `cdktf.json`

Previously we would throw an error and exit with 1 if there were no provider or
module specifications in the `cdktf.json` file. This can be inconvenient if
`cdktf get` is part of a workflow.

### `Fn.merge` is split into `Fn.mergeLists` and `Fn.mergeMaps`

The Terraform `merge` function can merge both lists and maps, but this can cause
[issues](https://github.com/open-constructs/cdk-terrain/issues/1653) when using the
result in a typed language. Therefore we split it into `Fn.mergeLists` and
`Fn.mergeMaps`, this means you need to change your cdktf programs code.