Public Key Directory
Key Transparency for the Fediverse
Details
- External ID
- 46728357
- Source
- HN
- Company
- —
- Product
- Public Key Directory
- Website domain
- publickey.directory
- Launched
- Jan. 23, 2026
- Cohort
- —
- Upvotes
- 5
- Upvotes percentile
- 0.09617918313570488
- Tags
- —
- Fetched at
- Sept. 7, 2026, 9:25 p.m.
- Updated at
- Sept. 7, 2026, 9:25 p.m.
Description
Specification: https://github.com/fedi-e2ee/public-key-directory-specificat...I've been working on solving this problem so we can have end-to-end encryption for DMs on ActivityPub (and therefore Mastodon).I thought I'd share it here in case anyone was interested in this work.
Enrichment
- Theme
- self-hosted infrastructure and security tools
- Vertical
- Security
- Function
- Compliance & governance
- Audience
- Developer
- AI stance
- Not AI
- Project type
- Commercial product
- Normalized one-liner
- key transparency for federated networks
- Manually corrected
- False
Could you build this?
No Designing and implementing an append-only cryptographic key transparency log with formal verification (ProVerif), post-quantum algorithms, and Merkle tree auditing requires specialized cryptographic protocol expertise.
What it would actually take: A production implementation requires distributed systems and cryptographic engineering using languages like Go or Rust for verifiable Merkle tree logs (similar to Google Trillian/Certificate Transparency). The hard parts include designing Byzantine fault-tolerant witness cosigning, GDPR-compliant verifiable redaction ('shreddable history') without breaking append-only proofs, and rigorous formal verification using tools like ProVerif to ensure zero protocol vulnerabilities.
Discussion
2 comments analyzed.
Competitors mentioned: FOKS
Concerns raised: Key directory can infer social graph through lookup metadata, Limited k-anonymity to same-instance users, ActivityPub already leaks social graph
Feature requests: Metadata resistance for non-ActivityPub e2ee systems
Competitors
Other products that read as similar to this one — 23 launches clear the similarity bar, closest 8 shown.
Attention rank: #22 of 24 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).
Looks like the first mover among its competitors.
- HushOS Drive · ph · 2026-09-18 · 6 upvotes · similarity 0.40
- Classified · ph · 2026-09-10 · 1 upvotes · similarity 0.36
- Secure Core FFI · ph · 2026-09-14 · 1 upvotes · similarity 0.35
- dpapi-toolkit · github · 2026-09-23 · 28 upvotes · similarity 0.34
- SelfCertForge, manage root CAs and self-signed certs on macOS/Windows · hn · 2026-05-13 · 5 upvotes · similarity 0.33
- CTlogs.io · ph · 2026-09-08 · 1 upvotes · similarity 0.33
- Authorize MCP tool calls without giving agents the credentials · hn · 2026-09-14 · 7 upvotes · similarity 0.32
- Keydentials · ph · 2026-09-29 · 1 upvotes · similarity 0.32
Other launches for this product
- No other launches for this product.
Same idea, different domain
Nobody's really built a compliance & governance tool for Media & entertainment yet.