UniSi — AI-Native Digital Signatures

UniSi is an open-source digital signature platform that businesses can self-host and run entirely under their own brand. It covers the full signing workflow — sending documents, collecting signatures, and verifying completion — without depending on a closed, third-party vendor.

AI does the tedious parts: it auto-detects and places signature and form fields on uploaded documents, and can draft a complete signing template from a plain-language prompt. Every completed document is checked against a tamper-evident, SHA-256 audit trail, so signers and senders can independently verify nothing changed after signing.

For developers, UniSi exposes a REST API, webhooks, and embeddable signing forms so the whole flow can be built into an existing product. It's available pay-as-you-go with $5 of free AI credit, with a white-label option for businesses that want it under their own name.