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libraries/katabasis/README.md

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+# Katabasis - MS-flavoerd OAuth for Qt, derived from the O2 library
+
+This library's sole purpose is to make interacting with MSA and various MSA and XBox authenticated services less painful.
+
+It may be possible to backport some of the changes to O2 in the future, but for the sake of going fast, all compatibility concerns have been ignored.
+
+[You can find the original library's git repository here.](https://github.com/pipacs/o2)
+
+Notes to contributors:
+
+   * Please follow the coding style of the existing source, where reasonable
+   * Code contributions are released under Simplified BSD License, as specified in LICENSE. Do not contribute if this license does not suit your code
+   * If you are interested in working on this, come to the MultiMC Discord server and talk first
+
+## Installation
+
+Clone the Github repository, integrate the it into your CMake build system.
+
+The library is static only, dynamic linking and system-wide installation are out of scope and undesirable.
+
+## Usage
+
+At this stage, don't, unless you want to help with the library itself.
+
+This is an experimental fork of the O2 library and is undergoing a big design/architecture shift in order to support different features:
+
+* Multiple accounts
+* Multi-stage authentication/authorization schemes
+* Tighter control over token chains and their storage
+* Talking to complex APIs and individually authorized microservices
+* Token lifetime management, 'offline mode' and resilience in face of network failures
+* Token and claims/entitlements validation
+* Caching of some API results
+* XBox magic
+* Mojang magic
+* Generally, magic that you would spend weeks on researching while getting confused by contradictory/incomplete documentation (if any is available)