Methodology

Definitions before rankings.

BIR is a historical registry for cross-chain bridge incidents and their aftermath. It is not a live safety ranking and not a recommendation engine.

Scope boundary

BIR records what happened, what changed, and what remains uncertain after bridge incidents. It does not publish exploit reproduction steps, attack instructions, or bridge safety rankings.

Scope

What BIR records

A record may describe a bridge entity, an incident case, an aftermath event, or a source used as evidence.

Bridge entity

A bridge, router, messaging protocol, or interoperability system that may have one or more incident records.

Incident case

An exploit, pause, migration, shutdown, recovery, reimbursement, or other historically significant bridge incident.

Evidence

Official statements, postmortems, analytics reports, security writeups, media coverage, or archived pages used to support claims.

Maturity

Record maturity and freshness

BIR separates how complete a record is from how recently it was reviewed.

stub: Minimal placeholder with limited verified facts.
reviewed: Core facts checked against source material.
full: Expanded record with timeline, evidence, and known uncertainty.
current: Reviewed recently enough for the record scope.
stale: May still be useful, but needs a later review.
needs_review: Known issue, missing source, or uncertain claim requires review.
under_revision: Record is being actively corrected or expanded.

Evidence

Source handling

BIR prefers primary and well-attributed sources. Lower-tier sources can provide context, but should not alone establish major claims.

Tier 1: Official postmortem, project statement, court/regulatory source, or analytical report with clear methodology.
Tier 2: Security firm writeup, blockchain analytics article, major crypto media report, or archived official material.
Tier 3: Community post, social thread, database entry, or secondary summary.
Conflicts: Conflicting claims should be kept visible with source links and resolution notes.
Quotes: Use short excerpts only. Prefer paraphrase, attribution, and source URLs.

Amounts

Reported loss and recovery amounts

Amounts are treated as claims, not automatic facts.

Reported loss values may differ across official posts, analytics reports, security writeups, and media coverage. BIR stores the selected display value together with confidence, source links, and conflicting claims where needed.

Uncertainty

Known unknowns

Unknown values are part of the record, not a failure of the record.

null: Information is missing or not yet entered.
unknown: The question was considered, but no reliable answer is currently known.
not_applicable: The field does not apply to this record.
is_unresolved: The final recovery, reimbursement, restart, or outcome is not yet sufficiently verified.