A signing library,
inside your network.
A standalone library that drops into C#, Java, Python or Go — so your documents are signed, counter-signed and stored without ever crossing your network boundary.
One library, every language.
The standalone library ships as a native package for the languages your stack already speaks — same API, same behaviour.
C# & .NET
Java
Python
Go
+ bindings for Node.js, Rust and PHP on request
Your documents never leave home.
With the standalone library, the document stays inside your organisation's network. The library runs in-process — no upload, no round-trip, no boundary crossed.
- ✓ Library executes in-process, beside your application
- ✓ No document leaves the network perimeter
- ✓ Signed files are written straight to local disk
Sign your way. Trust, optional.
Choose how a document is signed — handwritten or digital — and decide whether to counter-sign with a Gravixia certificate for cross-border standing.
Handwritten Signature
Capture a wet-ink or drawn signature directly inside the application — straight onto the document.
Digital Signature
Cryptographically sign with your own PFX certificate. The private key stays where it already lives — inside your infrastructure.
Counter-sign by Gravixia
At the end of the flow the document can be counter-signed with a Gravixia certificate. This establishes trust in international court.
Stored on local disk
The signed document is written straight to your local disk — not to Gravixia Cloud. You decide where it lives, and who gets to read it.
Pay per envelope. Nothing more.
The library itself is free. You pay only for each envelope you sign, with an active Gravixia subscription as the single requirement.
Drop the standalone library into any project — there is no per-seat or per-install fee.
Pricing is metered by the envelope. You pay only when an envelope is sealed and signed.
A current Gravixia subscription is the only prerequisite for using the standalone library in production.
Your network. Your disk. Your terms.
Documents are signed and stored where they already live — nothing leaves the organisation, nothing touches the cloud.