---
title: "DEWS"
canonical: "https://pharos.watch/docs/dews/"
description: "Depeg Early Warning System methodology: DEWS formula, stress sub-signals, bands, downgrade gates, and API response contract."
---

# Depeg Early Warning Score (DEWS)

Per-coin, forward-looking stress score (0-100) for depeg stress. It is not a calibrated probability. Computed every 30 minutes from 8 sub-signals.

## Methodology Versioning

DEWS shares its methodology versioning with the Depeg Tracker pipeline. Both are tracked together in `shared/lib/depeg-dews-version.ts`.

- **Current methodology version:** `v6.01`
- **Public changelog page:** `/methodology/depeg-changelog/`
- **Canonical source:** `shared/lib/depeg-dews-version.ts`

Each API response includes the shared `methodology` envelope with `version`, `versionLabel`, `currentVersion`, `currentVersionLabel`, `changelogPath`, `asOf`, and `isCurrent` fields.

---

## Score Formula

```
base  = sum(W_i * S_i) / sum(W_i)          # available signals only
psiAmp = PSI < 75 ? 1 + ((75 - PSI) / 75) * 0.3 : 1.0
contagionAmp = same-peg first-pass bump, currently 1.15 for DANGER or 1.08 for WARNING, clamped to 1.2
DEWS = round(clamp(0, 100, base * psiAmp * contagionAmp))
```

Only signals where `available = true` participate. Weights are redistributed proportionally across available signals.

**Minimum signal requirement:** At least 2 available signal sources (total weight >= 0.30). If weight is below 0.30, `computeDEWS()` returns `null` (insufficient data) instead of emitting `0/CALM`.

**Evidence-quality WATCH cap:** After the amplifier formula, `computeDEWS()` caps preliminary scores above `WATCH_MAX_SCORE = 35` back to WATCH when the evidence set has neither market-price evidence nor DEX-liquidity evidence and there is no severe issuer-control signal. Severe issuer-control evidence is a blacklist sub-signal at or above the configured severe threshold, so a real freeze/blacklist surge can exceed WATCH even without market or DEX corroboration. Capped rows carry `insufficientEvidenceReason = "data_quality_only"` when the stress is only data quality plus systemic backdrop, or `"missing_market_or_liquidity_evidence"` when other non-market evidence exists but market/DEX corroboration is missing.

**Systemic backdrop amplifier:** When PSI drops below 75 (STEADY band), individual DEWS scores are amplified by up to 30%. At PSI=40, amplification is ~14%. At PSI=0, amplification is 30%. This reflects that individual coin stress is more dangerous during systemic instability.

**Contagion Amplifier:** On top of the PSI amplifier, DEWS applies a bounded per-peg-type contagion amplifier derived from the same cycle's first-pass results. If any tracked stablecoin's first-pass band is `DANGER` (bump `1.15x`) or `WARNING` (bump `1.08x`), the other coins sharing its `pegType` are re-scored with that multiplier — the amplifier takes the largest qualifying bump, not a sum, so multiple DANGER coins on one peg type still cap at `1.15x`. The hard defensive cap is `1.2x` (`CONTAGION_AMPLIFIER_CAP`) for future bump values; different peg types do not share contagion risk. A coin that is itself `DANGER` or `WARNING` on the first pass does **not** contagion-amplify itself — its first-pass result carries forward unchanged. The resulting per-coin amplifier is surfaced on `/api/stress-signals` as `amplifiers.contagion` (default `1.0` when no contagion is detected or for legacy cached rows).

---

## Sub-Signals & Weights

| Signal                  | Key      | Weight | Data Source             | What It Detects                                                                      |
| ----------------------- | -------- | ------ | ----------------------- | ------------------------------------------------------------------------------------ |
| Supply Velocity         | `supply` | 0.25   | stablecoins cache       | Rapid redemptions (bank run)                                                         |
| Pool Balance Drift      | `pool`   | 0.20   | `dex_liquidity`         | One-sided selling pressure in DEX pools                                              |
| Liquidity Erosion       | `liq`    | 0.15   | `dex_liquidity_history` | LPs fleeing                                                                          |
| Price Confidence        | `price`  | 0.15   | stablecoins cache       | Oracle/data source failures                                                          |
| Cross-Source Divergence | `diverg` | 0.15   | `dex_prices` + cache    | Fragmented pricing, trust breakdown                                                  |
| Blacklist Activity      | `black`  | 0.10   | `blacklist_events`      | Issuer emergency freeze surge                                                        |
| Mint/Burn Flow          | `flow`   | 0.10   | `mint_burn_hourly`      | Redemption surge vs minting                                                          |
| Yield Anomaly           | `yield`  | 0.05   | `yield_data` + `yield-rankings` cache | Yield warning signals plus populated source-risk and rank-attribution stress evidence |

Weights sum to 1.15 but only available signals participate, so redistribution normalizes by actual available weight. When `S_flow` and `S_yield` are both unavailable (most coins), effective weight is 1.00 across the 6 original signals.

---

## Threat Bands

| Range  | Band        | Hex       | Description                            |
| ------ | ----------- | --------- | -------------------------------------- |
| 0-15   | **CALM**    | `#22c55e` | No stress signals detected             |
| 16-35  | **WATCH**   | `#14b8a6` | Mild stress on 1-2 indicators          |
| 36-55  | **ALERT**   | `#eab308` | Multiple indicators elevated           |
| 56-75  | **WARNING** | `#f97316` | Strong stress signals, depeg plausible |
| 76-100 | **DANGER**  | `#ef4444` | Severe stress across available weighted signals |

---

## Sub-Signal Details

### S_supply — Supply Velocity

Measures supply contraction rate. Only negative changes contribute stress.

- **1d normalization:** `[0%, 0] → [1%, 15] → [3%, 40] → [5%, 65] → [10%, 85] → [20%, 100]`
- **7d normalization:** `[0%, 0] → [3%, 15] → [7%, 40] → [15%, 70] → [30%, 100]`
- **Blend:** `0.6 * norm1d + 0.4 * norm7d`
- **Size dampening:** `sizeFactor = min(1, log10(max(mcap, $1M) / $1M) / 3)` — small coins (<$50M) get reduced signal

### S_pool — Pool Balance Drift

DEX pool imbalances from `dex_liquidity`. Blends:

- 40% balance stress (1 - weighted_balance_ratio)
- 35% pool stress score (avg_pool_stress)
- 25% worst single pool imbalance (from top_pools_json)

Smoothed with previous reading when available.

### S_liq — Liquidity Erosion

7-day change in liquidity score and TVL from `dex_liquidity_history`.

- **Score erosion anchors:** `[0%, 0] → [5%, 15] → [15%, 40] → [30%, 70] → [50%, 100]`
- **TVL erosion anchors:** `[0%, 0] → [10%, 15] → [25%, 40] → [50%, 70] → [75%, 100]`
- 50/50 blend
- **Fail-closed:** current liquidity score is required, and at least one of the score or TVL 7-day anchors must be available. If both anchors are missing, the sub-signal is unavailable; if one anchor is missing, that side contributes 0 to the 50/50 blend.

### S_price — Price Confidence Degradation

Maps `priceConfidence` field: high=0, single-source=25, low=60, fallback=80, null price=100.
+15 transition bonus when confidence degrades from previous reading.

### S_diverg — Cross-Source Price Divergence

Max of: primary deviation from peg, DEX deviation from peg, cross-source spread (all in bps).

- DEX input comes only from `dex_prices` rows refreshed within the live depeg trust window (`DEX_FRESHNESS_SEC = 2100`, currently 35 minutes) **and** backed by at least `$1M` of aggregate source TVL, matching the live depeg trust floor
- **Anchors:** `[0bps, 0] → [25bps, 10] → [50bps, 25] → [75bps, 50] → [100bps, 75] → [200bps, 90] → [500bps, 100]`
- **Non-USD peg dampening:** `value *= 0.7`
- Smoothed with previous reading.

Historical `stress_signal_history` rows do not retain the underlying DEX trust metadata (`source_total_tvl`, per-row freshness context) needed to replay this gate exactly. The Wave 5.9 repair path therefore refreshes current rows and prunes unrecomputable daily history from the Mar 9, 2026 trust-floor boundary onward instead of pretending those stored snapshots can be deterministically recomputed.

### S_black — Blacklist Activity

Only for symbols in the shared `BLACKLIST_STABLECOINS` set (`shared/types/market.ts`). Coverage is derived from the same supported blacklist symbol set as the live blacklist tracker instead of maintaining a separate DEWS-local coin list. Uses 24h event count with spike detection relative to 7d daily average.

### S_flow — Mint/Burn Flow

Available only when `mint_burn_hourly` data exists and is >= 7 days old. A mature 30-day baseline with zero mint/burn activity in the latest 24h window still counts as available data and contributes zero flow stress. Measures:

- **Burn surge:** 24h burn volume / 30d daily average
- **Burn-to-mint ratio:** 24h burns / 24h mints
- 60/40 blend of surge and ratio scores

### S_yield — Yield Anomaly

Available for yield-bearing coins with warning signals in `yield_data` or populated structured yield stress in the published `yield-rankings` cache. Maps active warning signals to stress points:

| Warning Signal     | Points |
| ------------------ | ------ |
| `yield-spike`      | 30     |
| `yield-divergence` | 25     |
| `tvl-outflow`      | 35     |
| `negative-trend`   | 15     |
| `reward-heavy`     | 20     |

Score = `min(100, sum of active signal points)`.

Structured Yield Intelligence source-risk and rank-attribution evidence adds these stress points inside the same Yield Anomaly sub-signal:

| Structured input | Points |
| --- | ---: |
| `sourceRisk.rewardShare > 0.5` | 20 |
| `sourceRisk.sourceDepthRatio < 0.001` | 35 |
| `sourceRisk.sourceAgeSeconds > 6h` | 15 |
| `sourceRisk.sourceSwitchCount30d > 0` | 20 |
| `sourceRisk.sourceRiskPenalty >= 1.5` | 20 |
| `sourceRisk.venueRiskTier = "high"` | 25 |
| `rankChangeAttribution.primaryDriver = "source-switch"` | 20 |
| `rankChangeAttribution.primaryDriver = "source-risk"` | 20 |

Structured evidence is additive with warning-string evidence and the final Yield Anomaly sub-signal still caps at 100. Neutral structured rows do not become available zero-stress signals; missing, malformed, or neutral source-risk evidence remains a no-op so legacy warning-only behavior is preserved.

---

## Edge Cases

- **NAV tokens** (`flags.navToken`): Excluded entirely (price appreciates, not pegged)
- **Non-USD pegs:** S_diverg dampened by 0.7 factor (noisier FX pricing)
- **Small coins (<$50M):** S_supply dampened via size factor
- **No DEX data:** S_pool and S_liq marked unavailable, weight redistributed
- **No blacklist tracking:** S_black unavailable for most coins
- **New coins / no history:** Signals gracefully degrade to unavailable

---

## Data Pipeline

### Tables

| Table                   | Pruning  | Purpose                                |
| ----------------------- | -------- | -------------------------------------- |
| `stress_signals`        | 7 days   | 30-minute rolling samples              |
| `stress_signal_history` | 365 days | Daily snapshots (first run of UTC day) |

### Cron Schedule

**Trigger:** `26,56 * * * *` — DB-only DEWS/PSI lane. It runs after the normal `10,40 * * * *` DEX-liquidity slot, but it is a separate scheduled invocation so a DEX-liquidity CPU overrun cannot prevent DEWS publication.

**Cron name:** `compute-dews`

**Run health semantics:** DEWS records upstream read problems as structured cron metadata (`sourceFailures`, `sourceCoverage`, `validationFailures`). The cron returns `status: "degraded"` when non-bootstrap source dependencies fail. Bootstrap grace is now a one-time state transition, tracked by the `dews:bootstrap-complete` cache sentinel after the first successful publication. Before that first success, only explicitly optional missing tables are tagged `bootstrapAllowed=true`; once the sentinel exists, those same failures degrade the run normally. Stale `dex_liquidity` is treated as a core dependency failure and is recorded in metadata, but rows that meet signal-coverage requirements are still persisted.

**Off-chain confirmation resilience:** CoinGecko and DefiLlama confirmation fetches used by the pending-depeg pipeline are wrapped in a circuit breaker. A sustained provider outage trips the breaker and short-circuits subsequent confirmation lookups until it resets, so a single upstream failure no longer hammers the endpoint for 45 minutes per pending row.

**Data flow:**

1. Read stablecoins cache, derive peg rates with cached `fxFallbackRates` for thin non-USD groups
2. Read `dex_liquidity`, live-depeg-trusted `dex_prices`, and `dex_liquidity_history`
3. Read `blacklist_events` counts (24h + 7d)
4. Read previous `stress_signals` for smoothing
5. Read `mint_burn_hourly` aggregates
6. Read `yield_data.warning_signals` and structured `sourceRisk` / `rankChangeAttribution` evidence from the published `yield-rankings` cache
7. Compute DEWS per PSI-eligible coin
8. Batch write to `stress_signals` (only for coins where `computeDEWS()` returned a score)
9. Retire current `stress_signals` rows for PSI-eligible assets that are explicitly present in the stablecoins cache with zero current circulating supply
10. Daily snapshot to `stress_signal_history` (first run of UTC day)
11. Purge rows for IDs no longer in the current PSI-eligible universe (chunked ID deletes, 90 IDs/chunk, to stay under D1 bind-variable limits)
12. Prune old data

---

## API Endpoint

### `GET /api/stress-signals`

**All coins (no params):** Returns latest DEWS for readable tracked stablecoins. The response-level freshness headers use the latest aggregate publication timestamp (`updatedAt`) so one retained frozen/long-tail row does not stale the entire `/depeg` surface; `oldestComputedAt` remains in the body for consumers that need to detect per-coin lag. Pre-launch tracked entries are excluded because the handler gates on readable tracked IDs.

When a coin has insufficient data in a cycle (`computeDEWS() === null`), that run skips writes for the coin, so this endpoint continues serving the last valid cached row.

```text
{
  "signals": {
    "usdt-tether": { "score": 5, "band": "CALM", "signals": { ... }, "computedAt": 1740000000, "methodologyVersion": "6.0" },
    ...
  },
  "updatedAt": 1740000000,
  "oldestComputedAt": 1740000000,
  "malformedRows": 0,
  "methodology": { "version": "6.0", "versionLabel": "...", "currentVersion": "6.0", "currentVersionLabel": "...", "changelogPath": "/methodology/depeg-changelog/", "asOf": 1740000000 }
}
```

`updatedAt` is the newest current row in the aggregate response and is used for aggregate `X-Data-Age` / `Warning` freshness headers. `oldestComputedAt` is the oldest returned current row and is body-only for consumers that need per-coin lag detection.

**Single coin:** `?stablecoin=usdt-tether&days=30` (default 30, min 1, max 365) — Returns latest + daily history.

Unknown IDs return `404` with `Unknown stablecoin`; tracked-but-non-active IDs return `404` with `Stablecoin not tracked`.

```text
{
  "current": { "score": 5, "band": "CALM", "signals": { ... }, "computedAt": 1740000000, "methodologyVersion": "6.0" },
  "history": [
    { "date": 1739900000, "score": 3, "band": "CALM", "signals": { ... }, "methodologyVersion": "6.0" },
    ...
  ],
  "malformedRows": 0,
  "methodology": { "version": "6.0", "versionLabel": "...", "currentVersion": "6.0", "currentVersionLabel": "...", "changelogPath": "/methodology/depeg-changelog/", "asOf": 1740000000 }
}
```

**Cache:** standard (s-maxage=300, max-age=60)

### `GET /api/backfill-dews` (admin)

Validates DEWS against historical depeg events. The primary calibration path uses stored `stress_signal_history` rows plus curated anchors and reports precision, recall, false-positive days, false-negative incidents, lead-time P50/P90, alert churn, band-transition stability, and cohort metrics. The older supply/liquidity reconstruction remains a diagnostic path because it cannot replay every live signal or source-trust gate.

### `GET /api/backfill-dews?repair=...&dry-run=true` / `POST /api/backfill-dews?repair=...` (admin)

Repair modes:

- `repair=refresh-current`: preview or immediately republish current `stress_signals` rows under the live `$1M` DEX trust floor
- `repair=prune-history`: preview or delete bounded `stress_signal_history` windows that cannot be deterministically recomputed because the retained daily snapshots do not store the underlying DEX trust metadata

`GET` is accepted for the read-only backtest path and for repair previews with `dry-run=true`. Mutating DEWS repair runs require `POST`.

**Direct ops-api CLI example:** `CF-Access-Client-Id: <id>` and `CF-Access-Client-Secret: <secret>`

---

## Frontend Integration

| Component     | File                              | Location                                                                              |
| ------------- | --------------------------------- | ------------------------------------------------------------------------------------- |
| `DEWSBadge`   | `src/components/dews-badge.tsx`   | Table rows (hidden when CALM)                                                         |
| `DEWSDetail`  | `src/components/dews-detail.tsx`  | Stablecoin detail page; contextual methodology hint + footer links on the detail card |
| `DEWSSummary` | `src/components/dews-summary.tsx` | Homepage widget / depeg-page hero radar; title-level contextual methodology hint      |

**Hook:** `useStressSignals()` and `useStressSignalDetail(id, days)` in `src/hooks/api-hooks.ts`

**Classification constants:** `ThreatBand`, `THREAT_BAND_COLORS`, `THREAT_BAND_HEX`, `THREAT_BAND_LABELS` in `shared/lib/classification.ts`

**Design tokens:** `--dews-calm` through `--dews-danger`, plus radar contrast tokens (`--dews-radar-spoke`, `--dews-radar-calm-boundary`, `--dews-radar-band-ring-opacity`, `--dews-radar-outer-ring-opacity`, `--dews-radar-calm-dot-bloom`, `--dews-radar-calm-dot-core`) in `src/styles/tokens/semantic.css`

### Radar Layout (`DEWSSummary`)

The radar is center-is-danger: higher threat bands occupy inner rings, CALM coins form an ambient starfield at the periphery.

| Zone           | Radius range | Description                                                                     |
| -------------- | ------------ | ------------------------------------------------------------------------------- |
| Center label   | r 0–38       | `SCANNING` status label + total monitored count                                 |
| DANGER         | r 45–90      | Innermost elevated ring                                                         |
| WARNING        | r 95–140     |                                                                                 |
| ALERT          | r 143–175    |                                                                                 |
| WATCH          | r 178–208    | Outermost elevated ring                                                         |
| CALM starfield | r 212–238    | Non-interactive ambient dots (r=2 core + r=5 bloom, theme-aware opacity tokens) |
| Outer boundary | r 240        | Radar edge                                                                      |

Dashed ring boundaries are drawn at each zone's inner edge (r=45, 95, 143, 178) using the zone's threat color, plus a faint gray ring at r=212 delimiting the calm zone. Ring/spoke/calm-dot visibility is theme-aware via the DEWS radar tokens listed above. CALM dots are scattered deterministically using `deterministicRadiusOffset(id, 26)` from `src/lib/dews-radar-utils.ts`. The legend renders severity-order bands with live counts: `Danger (n)`, `Warning (n)`, `Alert (n)`, `Watch (n)`, `Calm (n)`. The `Calm` legend marker uses the same faint bloom+core star-dot treatment as the calm outer starfield.

---

## Alerting

DEWS has a dedicated outbound Telegram path via `dispatch-telegram-alerts`, scheduled every 5 minutes on the isolated `dispatch-telegram-alerts` cron. Subscriber filtering and dedupe behavior live in the Telegram alert subsystem, but DEWS remains surfaced through the normal read paths too:

- `GET /api/stress-signals`
- Telegram subscriber alerts (`dispatch-telegram-alerts`)
- Frontend components (`dews-badge`, `dews-detail`, `dews-summary`)