Re: Experimental did:cel Witness Service (open-source)

Manu, thank you. The oblivious witness concept is intriguing and holds
promise for decentralized systems.

The witness service implementation was straightforward, which encouraged me
to implement additional services covering the did:cel lifecycle. It binds
Google KMS with did:cel, allowing anyone to host their identifiers and it
contributes to greater diversity in the ecosystem.

https://github.com/filip26/iron-did-cel-witness

One of the other major did:cel features should be "infrastructure
democratization". I picture an ecosystem composed of services using HTTPS
endpoints, DIDComm, IFPS, or other protocols,  where you can manage
mission-critical DIDs that require high protection using an
enterprise-level solution with HSM protection, while other DIDs, like those
related to individuals, might reside on your mobile phone, and I’m happy to
contribute to this effort.

Feedback is welcome.

Best regards,
Filip
https://www.linkedin.com/in/filipkolarik/

On Sun, Mar 1, 2026 at 10:55 PM Patrick St-Louis <
patrick.st-louis@opsecid.ca> wrote:

> If there's compatibility, I don't see why the webvh information website
> couldn't reference it. I'm unsure about creating a hard dependency in the
> specification. We use a secure peer to peer DIDComm protocol for witness
> requests in our implementation, and are unlikely to implement an HTTP API
> interface in the foreseeable future. I believe other implementers have also
> defined their API services for witnessing, which should be taken into
> consideration.
>
> We debated including an API definition in the witness/watcher service, and
> opted to define only watchers because witness governance is outside of the
> WebVH spec, and implementers shouldn't be restricted by special
> infrastructure requirements. However as mentioned, I think providing a
> reference API definition could be interesting.
>
> Perhaps did:cel could also include a dependency on a witness DIDComm
> protocol. This would also be interesting.
>
> On Sun, Mar 1, 2026 at 4:40 PM Manu Sporny <msporny@digitalbazaar.com>
> wrote:
>
>> On Fri, Feb 27, 2026 at 11:51 AM Filip Kolarik <filip26@gmail.com> wrote:
>> > I’m excited to share an experimental witness service
>> >
>> > While designed for did:cel, the service can also be used to witness
>> arbitrary events, providing a lightweight, verifiable, and high-performance
>> proof layer for other decentralized or event-driven applications.
>>
>> This is awesome, Filip! I really like the fact that it highlights a
>> number of things:
>>
>> Oblivious witness services:
>>
>> 1. Can be simple and quick to build.
>> 2. Can be cost effective to operate.
>> 3. Can be lightning fast (with c14n templates).
>> 4. Can leverage industry standard HSMs.
>> 5. Can be generalized to any market vertical.
>>
>> Would you have any aversion to us writing down the API for the service
>> in a spec? It feels like it should be a separate, really lightweight
>> spec that both the CEL spec, and did:cel depend on. I'd love to see
>> did:webvh depend on it as well, thoughts on that from the did:webvh
>> folks?
>>
>> -- manu
>>
>> --
>> Manu Sporny - https://www.linkedin.com/in/manusporny/
>> Founder/CEO - Digital Bazaar, Inc.
>> https://www.digitalbazaar.com/
>>
>>