# Creating and sharing a CircuitPython library ## Overview Open source software is awesome. It's a shared resource that we all work on to benefit ourselves and others all at once. CircuitPython is built on the open source code of MicroPython for example. One challenge of open source software is making your code and documentation available in a way that makes it accessible to those that use it. It's not just a matter of writing code and posting it somewhere on the internet. For the core of CircuitPython we have existing source control on [GitHub](https://github.com/adafruit/circuitpython), low-level documentation on [ReadTheDocs](http://circuitpython.readthedocs.io/en/latest/), continuous testing on [GitHub Actions](https://github.com/features/actions), tutorials on [Adafruit Learn System](https://learn.adafruit.com/search?q=circuitpython&), community support on the [Adafruit Forums](https://forums.adafruit.com/viewforum.php?f=60) and live chat on [Discord](https://adafru.it/discord). However, there is much more to CircuitPython than just the core code. There are also additional libraries that expand what can be done on CircuitPython. They may add additional support for a particular FeatherWing or making simple tasks easier. To make CircuitPython libraries easy to find and understand we've come up with a number of best practices when creating a new library. This guide is an overview of those practices with links to more information on specific topics. - [Next Page](https://learn.adafruit.com/creating-and-sharing-a-circuitpython-library/creating-a-library.md) ## Featured Products ### Circuit Playground Express [Circuit Playground Express](https://www.adafruit.com/product/3333) **Circuit Playground Express** is the next step towards a perfect introduction to electronics and programming. We've taken the original Circuit Playground Classic and made it even better! Not only did we pack even more sensors in, we also made it even easier to... In Stock [Buy Now](https://www.adafruit.com/product/3333) [Related Guides to the Product](https://learn.adafruit.com/products/3333/guides) ### Adafruit Feather M0 Express [Adafruit Feather M0 Express](https://www.adafruit.com/product/3403) At the Feather M0's heart is an ATSAMD21G18 ARM Cortex M0+ processor, clocked at 48 MHz and at 3.3V logic, the same one used in the new [Arduino Zero](https://www.adafruit.com/products/2843). This chip has a whopping 256K of FLASH (8x more than the Atmega328 or 32u4) and... Out of Stock [Buy Now](https://www.adafruit.com/product/3403) [Related Guides to the Product](https://learn.adafruit.com/products/3403/guides) ### Adafruit METRO M0 Express - designed for CircuitPython [Adafruit METRO M0 Express - designed for CircuitPython](https://www.adafruit.com/product/3505) Metro is our series of microcontroller boards for use with the Arduino IDE. This new **Metro M0 Express** board looks a whole lot like our [original Metro 328](https://www.adafruit.com/product/2488), but with a huge upgrade. Instead of the ATmega328, this Metro... In Stock [Buy Now](https://www.adafruit.com/product/3505) [Related Guides to the Product](https://learn.adafruit.com/products/3505/guides) ### Adafruit GEMMA M0 - Miniature wearable electronic platform [Adafruit GEMMA M0 - Miniature wearable electronic platform](https://www.adafruit.com/product/3501) The **Adafruit Gemma M0** is a super small microcontroller board, with just enough built-in to create many simple projects. It may look small and cute: round, about the size of a quarter, with friendly alligator-clip sew pads. But do not be fooled! The Gemma M0 is incredibly... In Stock [Buy Now](https://www.adafruit.com/product/3501) [Related Guides to the Product](https://learn.adafruit.com/products/3501/guides) ## Related Guides - [Adafruit Feather M0 Express](https://learn.adafruit.com/adafruit-feather-m0-express-designed-for-circuit-python-circuitpython.md) - [Adafruit Metro M0 Express](https://learn.adafruit.com/adafruit-metro-m0-express.md) - [Adafruit Circuit Playground Express](https://learn.adafruit.com/adafruit-circuit-playground-express.md) - [Wind Blowing Emoji Prop](https://learn.adafruit.com/wind-face-emoji.md) - [Deco Two-Key Feather Macro Pad](https://learn.adafruit.com/deco-two-key-keypad-macropad-circuitpython-feather.md) - [Dance-Reactive Tutu Sparkle Skirt](https://learn.adafruit.com/dance-reactive-tutu-sparkle-skirt.md) - [CircuitPython Hardware: ILI9341 TFT & FeatherWing](https://learn.adafruit.com/micropython-hardware-ili9341-tft-and-featherwing.md) - [Professor Bubbleton’s Breathing Head in a Jar](https://learn.adafruit.com/professor-bubbleton-s-breathing-head-in-a-jar.md) - [Soil Moisture Sensor with Circuit Playground Express and MakeCode](https://learn.adafruit.com/soil-moisture-sensor-with-circuit-playground-express.md) - [Custom Controllers for MakeCode Arcade](https://learn.adafruit.com/custom-controllers-for-makecode-arcade.md) - [Mouse Painter: Emulate Mice with MakeCode ](https://learn.adafruit.com/mouse-painter-emulate-mice-with-makecode.md) - [Gemma 3D Printed Tree Topper](https://learn.adafruit.com/gemma-3d-printed-tree-topper.md) - [Using MCP23008 & MCP23017 with CircuitPython](https://learn.adafruit.com/using-mcp23008-mcp23017-with-circuitpython.md) - [Perfect Pitch Machine](https://learn.adafruit.com/perfect-pitch-machine.md) - [How to Program SAMD Bootloaders](https://learn.adafruit.com/how-to-program-samd-bootloaders.md) - [Sensor Plotting with Mu and CircuitPython](https://learn.adafruit.com/sensor-plotting-with-mu-and-circuitpython.md) - [Magical Cardboard Craft Obsidian Sword](https://learn.adafruit.com/cardboard-obsidian-sword.md) - [Hammer Time Mini Golf Hazard with Crickit](https://learn.adafruit.com/mini-golf-hammer-time-circuit-playground-crickit.md)