VOICEN is an open source project to build voice-enabled devices. Check this project at http://voicen.io/.
The first goal of the project is to make an open source smart speaker. With an open source smart speaker, you have the freedom to choose which voice assistant to use. You have full control of your device to install apps and to share your data.
The first hardware of the project is a DIY smart speaker kit - VOICEN Linear 4 Mic Array Kit.
The kit lets you build a smart speaker from scratch. It can run a variety of voice assistants such as Amazon Alexa, Google Assistant, MyCroft, Snips Offline Voice Assistant and Baidu DuerOS. It supports AirPlay and UPnP/DLNA. You can turn it into a music box with Mopidy and MPD, or use it to automate your home with Home Assistant.
Check this video of assembling the first prototype of VOICEN Linear 4 Mic Array Kit, to build a smart speaker from scratch: