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Announcing DIDsign, a New Application Built on KILT

We are delighted to announce the launch of DIDsign, a decentralized way to sign and verify files privately and securely. DIDsign is designed to make online services more convenient and safer in Web3, the next generation of the internet.

DIDsign allows you to sign any digital file — PDFs, audio, video, software — directly in your browser using a unique decentralized identifier (DID). You can download your signed file (or group of files) together with the signature to your device as a zip file and send it to anyone via your preferred method (email, Telegram, WhatsApp, etc.). The recipient can then easily verify that the file has not been tampered with. Signing, sending and verifying files is always free!

Using DIDsign, several people can sign the same document separately and confirm that it was signed. For example if a contract needs to be approved by several parties, each party can sign it and send their signature to the others. The document can then be checked against each signature, showing that each party signed the document in its original form.

Real-world use cases

With DIDsign, documents can be signed by anyone with an on-chain KILT DID. The recipient can then verify the files on — no blockchain experience needed! Only the sender and recipient have access to the files; they are not stored anywhere else. This provides a safe and private way of signing files.

In addition to text documents, DIDsign can be used for signing a video file, making sure it came from the right person and hasn’t been tampered with. Researchers could use DIDsign for verifying new research discoveries; doctors could use DIDsign for signing and verifying lab reports with colleagues in clinical settings. Developers could use DIDsign for signing software — if a single line of code is changed, the signature isn’t valid.

And DIDsign provides a new mechanism for Web3 processes like signing contracts in DAOs (decentralized autonomous organizations) or in the metaverse. Your avatar could even have its own DID for signing contracts. Decentralized ownership needs decentralized signatures.

DIDsign was built on KILT by B.T.E. BOTLabs Trusted Entity GmbH (BTE), a subsidiary of BOTLabs GmbH, the initial developer of KILT Protocol.

How to Create DIDs on KILT

A digital identity contains your own unique “decentralized identifier” (DID), a string of numbers and letters that looks like this:


You can create your DID for free using Sporran, a wallet for KILT Coins and credentials developed by BTE. In order to use DIDsign, you’ll need to upgrade your free DID to an on-chain DID in Sporran, which anchors it on the KILT blockchain.

On-chain DIDs require a deposit of 2 KILT Coins and a small transaction fee (currently less than 0.01 KILT). This deposit remains on your account and is unlocked if you later delete your on-chain DID.

DIDsign can be used in large enterprises in a scalable way. While each signer requires an on-chain DID, the deposit and fees don’t necessarily need to be paid by the owner of that DID. Instead, businesses could pay the KILT Coin deposits for employee DIDs. In this way employees don’t face any of the hurdles that first-time users may have when buying crypto.

Your data under your control

Unlike centralized services that currently offer digital signatures, DIDsign does not store any data. You sign and store the files locally on your personal device (laptop or mobile) without external servers, providing privacy by design. Using the DIDsign website, the file recipient can quickly and easily verify that the signature is valid and that the contents have not been changed in any way since signing.

How does it work?

Signing with DIDsign requires a Sporran wallet (setup instructions here) and an on-chain DID.

Once you have set these up, you can use this step-by-step guide to sign your files, or follow the walkthrough below:

Step 1: Go to DIDsign,io.

Step 2: Drag and drop the files you want to sign into the dropzone, or add them from your device.

Step 3: Click the blue “SIGN” button below the files.

This triggers a Sporran pop-up.

Step 4: Enter your password in the Sporran to sign the files. (Please note, if you accidentally close Sporran during this process, click “DISMISS” on the “Signature needed” pop-up to restart.)

Step 5: Save the signed files with the signature file in one zip file that can be easily sent via email etc.

That’s it!

The recipient then goes to the “VERIFY” section on the DIDsign website and adds the zip file.

DIDsign now verifies that the signature matches the file contents and the on-chain DID on the KILT blockchain. If the file was not changed and the DID matches the signature, then a green checkmark is displayed:

If files have been altered, the verification fails and DIDsign shows an orange exclamation mark:

The signer should share their DID with the recipient so that they can make sure the files come from the right person:

DIDsign also integrates verification of credentials issued by trusted entities such as SocialKYC, adding extra layers of security to the signed files. SocialKYC is an attestation service built on KILT that confirms ownership of your accounts (email, Twitter, Discord, GitHub) after you prove that you control them.

If users choose to make some of these credentials public, by exposing them via service endpoints of their DID, recipients will have more evidence about who signed the file than in Web2 solutions.

Future versions of DIDsign will also include the ability to:

  • Include KILT credentials directly in a signed file
  • Add a unique name to your DID
  • Self-attest timestamps anchored on the KILT blockchain at the time of signing.

Keep up-to-date with these new developments by following the KILT blog and Twitter, or join the conversation on Discord.

About KILT Protocol

KILT is a decentralized blockchain identity protocol for issuing self-sovereign, anonymous and verifiable credentials. KILT’s mission is to return control over personal data to its owner, restoring privacy to the individual. Developers can use KILT’s open-source Javascript SDK to quickly build applications for issuing, holding and verifying credentials and create businesses around identity and privacy.

About B.T.E. BOTLabs Trusted Entity GmbH

B.T.E. BOTLabs Trusted Entity GmbH (BTE) is a subsidiary of BOTLabs GmbH, a blockchain R&D company founded in 2018 and based in Berlin.

BOTLabs GmbH is the initial developer of KILT Protocol, now a fully decentralized blockchain identity network for issuing self-sovereign, anonymous and verifiable credentials. BOTLabs GmbH is a founding member of the International Association for Trusted Blockchain Applications (INATBA) and the Decentralized Identity Foundation (DIF), and a member of Blockchain for Europe.

BTE collaborates with developers, enterprise and government to build applications that enhance and protect digital identity across gaming, metaverse, health care, IoT, media, academia, energy, sustainability and more. The Sporran wallet, Stakeboard platform, SocialKYC attestation and DIDsign are the first applications developed by BTE.



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KILT Protocol

KILT is a blockchain identity protocol for issuing self-sovereign, verifiable credentials. KILT is part of the Polkadot ecosystem.