Backend Services

Supported Backends

ovos-core supports multiple backends under a single unified interface

  • Personal backend - self hosted
  • Selene -
  • OpenVoiceOS API Service -
  • Offline - support for setting your own api keys and query services directly

Developers do not need to worry about backend details in their applications and skills

API Offline Personal Selene OVOS
Admin yes [1] yes no no
Device yes [2] yes yes yes [4]
Metrics yes [2] yes yes yes [4]
Dataset yes [2] yes yes yes [4]
OAuth yes [2] yes yes yes [4]
Wolfram yes [3] yes yes yes
Geolocate yes yes yes yes
STT yes [3] yes yes yes
Weather yes [3] yes yes yes
Email yes [3] yes yes yes
[1] will update user level mycroft.conf
[2] shared json database with ovos-config-assistant and ovos-backend-manager
[3] needs additional configuration (eg. credentials)
[4] uses offline_backend functionality

Identity Information

A unique uuid and pairing information generated by registering with Home is stored in: ~/.config/mycroft/identity/identity2.json <-- DO NOT SHARE THIS WITH OTHERS!

This file uniquely identifies your device and should be kept safe

STT Plugin

a companion stt plugin is available to use a backend as remote STT provider

edit your configuration to use ovos-stt-plugin-selene

  "stt": {
    "module": "ovos-stt-plugin-selene"

source code

Offline Backend

OVOS by default runs without a backend, in this case you will need to configure api keys manually

This can be done with OCA or by editing mycroft.conf

edit your configuration to use the offline backend

  "server": {
    "backend_type": "offline"


The official mycroft home backend is called selene, users need to create an account and pair devices with the mycroft servers.

This backend is not considered optional by MycroftAI but is not used by OVOS unless explicitly enabled

Selene is AGPL licensed: - backend source code - frontend source code

edit your configuration to use the selene backend

  "server": {
    "backend_type": "selene",
    "url": "",
    "version": "v1",
    "update": true,
    "metrics": true,
    "sync_skill_settings": true

Personal Backend

Personal backend is a reverse engineered alternative to selene that predates it

It provides the same functionality for devices and packs some extra options

It is not intended to serve different users or thousands of devices, there are no user accounts!

This is currently the only way to run a vanilla mycroft-core device offline

edit your configuration to use your own personal backend instance

  "server": {
    "backend_type": "personal",
    "url": "",
    "version": "v1",
    "update": true,
    "metrics": true,
    "sync_skill_settings": true

source code

Backend Manager

A web UI is provided to manage a personal backend instance

source code

Admin Api

personal backend provides a admin api that can be used to manage your devices

from ovos_backend_client.api import AdminApi

admin = AdminApi("secret_admin_key")
uuid = "..."  # check identity2.json in the device you want to manage

# manually pair a device
identity_json = admin.pair(uuid)

# set device info
info = {"opt_in": True,
        "name": "my_device",
        "device_location": "kitchen",
        "email": "",
        "isolated_skills": False,
        "lang": "en-us"}
admin.set_device_info(uuid, info)

# set device preferences
prefs = {"time_format": "full",
         "date_format": "DMY",
         "system_unit": "metric",
         "lang": "en-us",
         "wake_word": "hey_mycroft",
         "ww_config": {"phonemes": "HH EY . M AY K R AO F T",
                       "module": "ovos-ww-plugin-pocketsphinx",
                       "threshold": 1e-90},
         "tts_module": "ovos-tts-plugin-mimic",
         "tts_config": {"voice": "ap"}}
admin.set_device_prefs(uuid, prefs)

# set location data
loc = {
    "city": {
        "code": "Lawrence",
        "name": "Lawrence",
        "state": {
            "code": "KS",
            "name": "Kansas",
            "country": {
                "code": "US",
                "name": "United States"
    "coordinate": {
        "latitude": 38.971669,
        "longitude": -95.23525
    "timezone": {
        "code": "America/Chicago",
        "name": "Central Standard Time",
        "dstOffset": 3600000,
        "offset": -21600000
admin.set_device_location(uuid, loc)

OVOS API Service

OVOS Api Service is not a full backend, it is a set of free proxy services hosted by the OVOS Team for usage in default skills

device management functionality and user accounts do not exist, offline mode will be used for these apis

edit your configuration to use the OVOS backend

  "server": {
    "backend_type": "ovos",
    "url": ""

source code