DéjàDéjài
PROTOCOL//ARCHITECTURAL PROOF

No magic.
Just math.

Déjà's Automated Chain of Custody turns incidents into deterministic evidence: what failed, why it recurred, and the exact fixes that resolved it.

>SECURE_TRANSMISSION//MODE:DETERMINISTIC_LOOKUP

The pipeline

Each phase emits structured metadata, so every match is explainable and reviewable.

01 // INGEST

Capture evidence

Ingest incidents, stack traces, and linked context (deploys, alerts, tickets).

02 // ANALYZE

Extract signal

Normalize traces, strip noise, and isolate the error's stable signature.

03 // FINGERPRINT

Stable identity

Generate a deterministic fingerprint that survives refactors and churn.

04 // MATCH

Evidence-backed fix

Match recurrence to prior proven PRs—complete with confidence and gates.

CURRENT_PHASE: INGEST
incident + traces stable signature evidence-backed fix

Code-centric proof

> parse_trace() // emit fingerprint // match_fix()
NO_MAGIC: deterministic
12345678910111213141516171819202122232425
// 1) Normalize the trace to stable tokens
const normalized = stripNoise(trace)
.keepFrames( ["src/api", "src/utils"])
.collapseVendor();
// 2) Generate a deterministic fingerprint
const fp = sha256(
serialize({
error: normalized.errorType,
message: normalized.messageTemplate,
frames: normalized.stableFrames
})
);
// 3) Match the fingerprint to prior fixes with evidence gates
const candidates = index.lookup(fp);
const verified = candidates
.filter(c => c.gates.rate && c.gates.duration)
.sortBy(c => c.confidence)
.last();
return {
fingerprint: fp,
fix_pr: verified.pr,
confidence: verified.confidence,
evidence: verified.explain
};

Validation gates

Déjà doesn't guess. It qualifies matches using deterministic gates — so you can trust the "Verified Fix" as a repeatable outcome, not a coincidence.

Scope verification> GATE: SCOPE_VALIDATION
VERIFIED
PATH_MATCHsrc/api/users.ts
CONTEXTrecurrence-aligned
RISKlow
Blast-radius deviation> GATE: CHANGE_DEVIATION
REVIEW
FILES_TOUCHED2
DIFF_SIZE+16 / -3
ANOMALYnone
Duration gate> GATE: REOCCURRENCE_WINDOW
VERIFIED
WINDOWlast_24h
FREQ_AFTER_FIX0
CONFIDENCE0.93

Privacy by design

Déjà is built for regulated environments. You decide what's ingested. The system can be deployed to meet strict perimeter requirements.

CODE_ACCESS:no source ingestion
DATA_MIN:tokens + fingerprints
RETENTION:configurable
>PERIMETER_POLICY: customer_defined//AUDIT_LOGS: enabled

Ready to deploy the engine?

Start your vault, connect a repo, and let the evidence accumulate.