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VISION.md

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+# Android Upload Service Vision
+This document has the purpose of illustrating the vision behind this library and help you know more about the direction in which is going.
+
+## Goals
+- Provide an easy way of uploading files on all different Android versions
+- Make the upload service core as easy, performant and lightweight as possible, using latest technologies
+- The core should not depend on anything more than androidx libraries and kotlin runtime
+- Decouple library and protocol implementation from HTTP Stacks
+- Allow to implement integrations with third party services using standard protocols, without having to depend on
+proprietary or third party libraries
+- Always support latest Android version
+- Comply with Google best practices and recommendations
+- Comply with latest security recommendations
+- Use Kotlin best practices
+
+## I wrote an integration with a third party service. And now?
+If your integration is using third party dependencies (e.g. FTP plugin uses Apache Commons Net dependency) then your plugin is not suitable 
+for integration in the main codebase, but you retain full authorship of your work and you're free to publish it on your own.
+
+This is made on purpose to avoid turning this library into a massive monorepo with a bazillion of different third party dependencies 
+to keep updated, which is really heavy to maintain.
+
+Every author of something new which is an integration to a third party service is responsible for its maintenance, support and evolution.
+
+Get in touch by opening an issue, describing what you've done and from when it can be downloaded.
+Your work will be featured in the wiki with direct links.
+
+If your third party integration makes some modifications to upload service core, you are encouraged to make a PR with only those modifications, while
+keeping the rest of your work in your repo.
+
+If your integration depends solely on Upload Service core, all your implementations have been done using the `HttpStack` abstraction and you have automatic tests
+as well, then you can make a PR requesting it to be included in the main codebase. After a code review and approval, you will be the one responsible for the
+support and maintenance of the newly added integration. You can obtail write access as a contributor as well.
+
+## Things which are not going to happen
+- Rewrite in Java. Starting from version 4.x the library has been completely rewritten in Kotlin. It has 100% interoperability 
+with Java, but this is the language with which further development will be made.
+- Porting for Android API < 21. Starting from 4.x, all the previous support for APIs 18, 19 and 20 has been dropped. The main motivation is security.
+Android API < 21 does not guarantee TLS 1.2 and everything is left to single vendors. Moreover, minimum hardware device available for testing is an old
+Android 5.0. If you or your company are intereseted in such support, feel free to fork the project, add it yourself and maintain it.
+
+## This document is incomplete
+As any document on earth, this document is incomplete. If you have an idea and you can't figure out if it complies with the vision by reading this file, 
+get in touch and let's discuss about it :wink: