{
 "schema_version": "1.7.0",
 "id": "x_NXMC-2024-0047",
 "modified": "2026-10-19T02:33:38.839Z",
 "published": "2026-10-18T09:00:52.565Z",
 "summary": "ModernBERT-base: structural change at 5756c58 (2024-12-19)",
 "details": "ModernBERT-base: derived parameters 130.1M to 136.0M (+5.9M, +0.01 GB of bf16 weights); context window 512 to 8192 tokens (2024-12-19).\n\nRepository: https://huggingface.co/answerdotai/ModernBERT-base. Revisions from 5756c58a31a2478f9e62146021f48295a92c3da5 onward carry this change; a pin at fa3113d09d6dacfe5528708803dd92a62240237a or earlier does not.\n\nChanged keys:\n- max_position_embeddings: 512 -> 8192 (structural)\n\nThis record says what the change does mechanically. It is not a report that anything broke for anyone.",
 "affected": [
  {
   "ranges": [
    {
     "type": "GIT",
     "repo": "https://huggingface.co/answerdotai/ModernBERT-base",
     "events": [
      {
       "introduced": "5756c58a31a2478f9e62146021f48295a92c3da5"
      }
     ]
    }
   ],
   "database_specific": {
    "model": "answerdotai/ModernBERT-base",
    "previous_revision": "fa3113d09d6dacfe5528708803dd92a62240237a"
   }
  }
 ],
 "references": [
  {
   "type": "INTRODUCED",
   "url": "https://huggingface.co/answerdotai/ModernBERT-base/commit/5756c58a31a2478f9e62146021f48295a92c3da5"
  },
  {
   "type": "PACKAGE",
   "url": "https://huggingface.co/answerdotai/ModernBERT-base"
  },
  {
   "type": "WEB",
   "url": "https://www.neurarch.com/changes-feeds/models/answerdotai/ModernBERT-base.html"
  }
 ],
 "database_specific": {
  "source": "neurarch model change tracker",
  "model": "answerdotai/ModernBERT-base",
  "kind": "structural",
  "classes": [
   "structural"
  ],
  "changed_keys": [
   {
    "file": "config",
    "key": "max_position_embeddings",
    "before": 512,
    "after": 8192,
    "class": "structural"
   }
  ],
  "impact": {
   "memory": true,
   "serving": true,
   "tokenizer": false,
   "licence": null
  },
  "breaking": true,
  "breaking_rule": "https://www.neurarch.com/changes-feeds/advisories/index.json#breaking_rule",
  "consequence": {
   "params": {
    "before": 130052352,
    "after": 135950592
   },
   "weightsGbBf16": {
    "before": 0.26,
    "after": 0.272
   },
   "trainPeakGb": {
    "before": 8.257,
    "after": 25.649
   },
   "fingerprint": null,
   "context": {
    "before": 512,
    "after": 8192
   },
   "eos": null,
   "bos": null
  },
  "commit_date": "2024-12-19T21:14:57.000Z",
  "detected_at": "2026-10-18T09:00:52.565Z",
  "detected_by": "backfill",
  "days_since_first_commit": 8,
  "license": "CC-BY-4.0"
 }
}