Public transparency log witness

Witness for https://api.fd0.sh

Independent observer of the fd0.sh server's signed tree heads. Consistency-verified observations are cosigned; fork evidence is archived and flagged. Pin the witness pubkey below in your client to require its cosign on every sync.

HEALTHYlast refresh 0s ago
Witness identity
pin this
URLhttps://witness.fd0.sh
Pubkey (ed25519)233848710d80517e…1ec7a383dc7cf567
Domainfd0-witness-cosign-v1
Add to ~/.fd0/config.toml:
[[witness]]
url = "https://witness.fd0.sh"
pub = "233848710d80517e09718e3d18abc4afd12fea4f4fb83b911ec7a383dc7cf567"

[witness_policy]
min_cosigns = 1
Observed chains (27)
watching https://api.fd0.sh
Chain IDTree sizeCosignsStatus
scope:s_3h7ty2l6wlhsuhcrzvibc3ixkmtree_size=1505105 cosigns✓ no fork
scope:s_7cs43lfdb53zdkdjodrzdgkeketree_size=41 cosigns✓ no fork
scope:s_efnkfuvrnkuhfvofgtjwwjr6latree_size=72 cosigns✓ no fork
scope:s_kig2kd4eytwqnq6cn42zh4x77itree_size=101 cosigns✓ no fork
scope:s_p2e2mb2rifsrxhg4zaoosrdwnytree_size=72 cosigns✓ no fork
scope:s_w25qav7mzmyii7dld2qio2655etree_size=6120 cosigns✓ no fork
scope:s_ygvhbly2rzclk7nk22tyc5kde4tree_size=3916 cosigns✓ no fork
scope:s_zajnqddgnm7sofg64rugoele5itree_size=41 cosigns✓ no fork
user:0ngv0pndtree_size=11 cosigns✓ no fork
user:36mnyp54tree_size=11 cosigns✓ no fork
user:5xeq1d0gtree_size=11 cosigns✓ no fork
user:7838y498tree_size=11 cosigns✓ no fork
user:789wrp0gtree_size=11 cosigns✓ no fork
user:7p41x93ntree_size=11 cosigns✓ no fork
user:86f2xah0tree_size=11 cosigns✓ no fork
user:9tmgntzqtree_size=11 cosigns✓ no fork
user:a6pypfz5tree_size=11 cosigns✓ no fork
user:atxy5jmztree_size=11 cosigns✓ no fork
user:b06tgea1tree_size=11 cosigns✓ no fork
user:cx9j1pyftree_size=11 cosigns✓ no fork
user:e58tzd5ctree_size=11 cosigns✓ no fork
user:j3by4p0gtree_size=11 cosigns✓ no fork
user:jdt6sqegtree_size=11 cosigns✓ no fork
user:p7g2n4rctree_size=11 cosigns✓ no fork
user:y3wsyvk2tree_size=11 cosigns✓ no fork
user:z2rtefm1tree_size=11 cosigns✓ no fork
user:ztbym5cwtree_size=11 cosigns✓ no fork
Verify yourself
curl + jq

The witness API is read-only and unauthenticated. Pull any STH and compare against what the server gave your client — the cosign should match.

$ curl -sS https://witness.fd0.sh/v1/server-info | cbor2json
{
  "witness_pub":     "0x233848710d80517e...",
  "witness_pub_hex": "233848710d80517e..."
}

# All chains the witness has archived for https://api.fd0.sh
$ curl -sS https://witness.fd0.sh/v1/observed/$(echo -n "https://api.fd0.sh" | basenc --base64url -w0 | tr -d '=')
What this guarantees

Both tables matter. Listing a witness only makes it available; cross-checking stays off until min_cosigns is at least 1. The default is 0, which disables it entirely, so a config with the witness alone verifies nothing. With the policy set, every sync verifies the server's STH against this witness's cosign. If the server ever publishes a fork — two distinct root hashes at the same tree_size — the witness flags equivocation and your client refuses the sync. That makes server-side equivocation cryptographically detectable rather than a matter of trust.

Run your own witness: docs/TRANSLOG.md §8. The more independent witnesses, the harder undetected equivocation becomes.