ChirpStack is an open-source LoRaWAN network server for private and public networks. It includes a web interface for managing gateways, devices and tenants, integrations with cloud services and databases, and a gRPC-based API. It supports the common LoRaWAN regions, device classes A, B and C, and LoRaWAN versions 1.0 through 1.1. Around the server there are separate components, such as Concentratord and MQTT Forwarder for gateways, and an open-source Gateway OS for Raspberry Pi-based gateways and hardware from RAK, Dragino and Seeed. You install and operate ChirpStack yourself; it requires PostgreSQL, Redis and MQTT.
ChirpStack is distributed under the MIT licence and was written by Orne Brocaar, who offers commercial support. Because you run ChirpStack yourself, device and network data stay on the infrastructure you choose, and the source code is open to inspection. For a European organisation this means full control over hosting and data, with the trade-off that operation and maintenance rest with you or a support partner.