---
layout: page
published: true
noToc: true
noComments: false
noDate: false
title: Fun - External integrations (optional extensions)
subtitle: Catalog of all example scripts under ./examples/, what each area contains, how to run them, required env vars, and extension requirements.
description: Catalog of all example scripts under ./examples/, what each area contains, how to run them, required env vars, and extension requirements.
permalink: /documentation/external/
lang: en
tags:
- documentation
- handbook
- installation
- usage
- introduction
- help
- guide
- howto
- docs
- specifications
- specs
- repl
---

# External integrations (optional extensions)

This section documents Fun's optional, build-time selectable extensions. Each page covers:
- How to enable the extension via CMake option (FUN_WITH_*)
- Build requirements and detection notes
- Available opcodes and/or helper functions
- Minimal usage examples and links to example scripts

## Extensions:

- [cURL (libcurl)](./curl/)
- [INI (iniparser)](./ini/)
- [JSON (json-c)](./json/)
- [libxml2 (XML)](./xml2/)
- [SQLite](./sqlite/)
- [PCRE2 (Perl-compatible regex)](./pcre2/)
- [PC/SC (Smart cards)](./pcsc/)
- [OpenSSL](./openssl/)

## Notes:

- These integrations are optional; the VM compiles without them.
- When disabled, related builtins usually return empty strings/neutral values rather than fail hard, mirroring existing optionality patterns.