Open Source Attribution
xthAB Limited, England and Wales
1. Our Commitment to Open Source
Villip is built entirely on Free and Open Source Software (FOSS). We are deeply grateful to the open source community whose work makes carrier-grade communications infrastructure accessible. This page lists the key open source projects and libraries that power the Villip platform.
While Villip itself is a proprietary product of xthAB Limited, we are committed to contributing back to the open source ecosystem where possible and to respecting the licence terms of every project we use.
2. Infrastructure and Platform
The following FOSS projects form the foundation of the Villip platform:
| Project | Licence | Role |
|---|---|---|
| Go | BSD-3-Clause | Backend runtime and API services |
| SvelteKit | MIT | Product website and tenant portal |
| PostgreSQL | PostgreSQL Licence | Primary transactional database |
| Valkey | BSD-3-Clause | Cache, session state, and rate limiting |
| Apache Kafka | Apache-2.0 | Event streaming and CDR pipeline |
| Kamailio | GPLv2 | SIP signalling proxy and session border controller |
| FreeSWITCH | MPL-1.1 | Media server for voice, conferencing, and recording |
| RTPengine | GPLv3 | RTP/SRTP media relay and transcoding |
| Caddy | Apache-2.0 | Web server and reverse proxy with automatic TLS |
| K3s | Apache-2.0 | Lightweight Kubernetes distribution |
| Linkerd | Apache-2.0 | Service mesh with mTLS |
| Prometheus | Apache-2.0 | Metrics collection |
| Grafana | AGPLv3 | Monitoring dashboards |
| OpenSearch | Apache-2.0 | Log aggregation and search |
| OpenBao | MPL-2.0 | Secret management and encryption |
| MinIO | AGPLv3 | Object storage for recordings and media |
| Gitea | MIT | Self-hosted source control |
3. Go Libraries
Key open source Go libraries used in the Villip backend:
| Library | Licence | Purpose |
|---|---|---|
| jackc/pgx | MIT | PostgreSQL driver and connection pool |
| valkey-glide | Apache-2.0 | Valkey client |
| google/uuid | BSD-3-Clause | UUID generation |
| stripe/stripe-go | MIT | Payment processor integration |
| segmentio/kafka-go | MIT | Kafka producer and consumer |
| gRPC-Go | Apache-2.0 | Internal service mesh communication |
| Protocol Buffers | BSD-3-Clause | Service interface definitions |
| golang.org/x/crypto | BSD-3-Clause | Argon2id password hashing |
4. Frontend Libraries
Open source libraries used in the Villip website and portal:
| Library | Licence | Purpose |
|---|---|---|
| Svelte / SvelteKit | MIT | UI framework and server-side rendering |
| Vite | MIT | Build tool and development server |
| Fontsource (Inter) | OFL-1.1 / MIT | Self-hosted Inter typeface |
| Stoplight Elements | Apache-2.0 | Interactive API documentation renderer |
5. Licence Compliance
xthAB Limited complies with all applicable open source licence terms. Where required by copyleft licences (GPL, AGPL), source code modifications to those specific components are made available upon request.
All proprietary Villip application code is developed independently and does not incorporate copyleft-licensed code via linking or embedding. Copyleft infrastructure components (Kamailio, FreeSWITCH, RTPengine, Grafana, MinIO) run as standalone processes and communicate with Villip services exclusively via network protocols.
6. Contact
For questions about our use of open source software, licence compliance, or to request source code where required by applicable licences, contact us at hello@villip.xyz.