Blog

This post calculates the size of a Beacon Signal in vbytes and divides that size across an aggregation cohort. It shows why on-chain fees are usually a small part of the cost of a did:btcr2 deployment.

Bitcoin finality is probabilistic, so the current version of a DID is also probabilistic. One confirmation threshold for all updates is a poor design, because the safe direction depends on what the update does.

A resolver finds Beacon Signals through a query of address history, and Bitcoin Core has no index for this query. The choice between an indexed RPC and your own scan of the blocks is a trust decision, not a capacity decision.

Bitcoin stores the commitment permanently. It does not store the data that explains the commitment. In did:btcr2, this gap is the problem of the controller, and it increases with each update.

Credential issuance is the easy half. This post shows how Bitstring Status List works, how a status check can cancel the privacy of selective disclosure, and what each alternative costs.

If one laptop key controls a company DID, that key is a liability. This post shows the custody options for BIP340 document signatures and where the tools still have gaps. It also explains why the beacon key is a separate custody problem.

btcr2 rotates keys without a dedicated recovery key, and the old key signs the update that replaces it. This post explains the rotation rules and what a contested rotation does to a DID.

This post reads did:nostr v0.1.1 closely. It shows the three resolution paths of the draft and why a projection of replaceable events is not an append-only history. It also shows which lifecycle operations the draft does not specify.

Nostr identity uses public keys, as DIDs do. This post shows where the two models align and where they can interoperate.

Enterprises can use decentralized identity for more than consumer wallets. This post shows real use cases in supply chains and B2B trust.

Lessons from the TypeScript implementation: sans-I/O patterns, branded types, builder and options APIs, and explicit dependency injection.

The threat model for DIDs with one canonical history, and how btcr2 finds and rejects late-publishing attacks.

How to issue, hold, and verify credentials with DIDs that are anchored to Bitcoin.

How decentralized identifiers remove password databases from servers and remove the dependency on one identity provider.

How the btcr2 spec and its reference implementation use MuSig2 n-of-n Schnorr multi-signatures and Nostr relays for beacon aggregation.

How the 256-bit SMT Beacon puts many DID updates behind one Merkle root on Bitcoin. An optional per-leaf nonce hides which DIDs have an update.

Techniques that let you prove a claim about yourself and keep the data behind the claim private.

How sidecar delivery keeps DID documents off public registries and lets you use a different DID for each relationship.

Practical steps to resolve Bitcoin-anchored DIDs in your applications.

How the bip340-jcs-2025 cryptosuite uses Bitcoin-native Schnorr signatures over secp256k1 for W3C Data Integrity proofs.

A detailed look at the three Beacon Types of did:btcr2 (Singleton, CAS, SMT) and how aggregation divides on-chain costs.

This post gives a technical description of the Sidetree-on-Bitcoin design of ION. It also gives an honest account of the current status of ION after Microsoft moved to did:web.

This post shows how Taproot activation, Schnorr signatures, and Bech32m encoding shaped the design decisions of btcr2.

This post shows how you derive btcr2 identifiers offline from secp256k1 keys or genesis documents. It also explains how this changes the economics of decentralized identity.

This post explains what btcr2 is and why the original BTCR needed a second version. It also shows how btcr2 adds zero-cost creation, stable identifiers, and private resolution.

A comparison of SSI with federated identity (OpenID Connect, OAuth, and SAML), and why the change is important for data ownership.

An overview of the DID specifications, the DID methods that use Bitcoin, and their outlook.

This post examines the tradeoffs of Bitcoin as an anchor for DIDs and compares Bitcoin with other approaches.