{
  "version": "v0.6",
  "updated": "2026-06-21",
  "strategy": "Chunk source metadata by year, theater, and source registry id so large archival imports can be lazy-loaded instead of rendered as one default layer.",
  "totals": {
    "source_points": 424
  },
  "chunks": {
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      {
        "key": "1939",
        "records": 2,
        "url": "/data/world-war-ii-atlas/sources-by-year/1939.geojson",
        "sha1": "6b0d4c212be9f74cc1e35cdf115138d6ea56a3ee"
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      {
        "key": "1941",
        "records": 1,
        "url": "/data/world-war-ii-atlas/sources-by-year/1941.geojson",
        "sha1": "f0337416952606e7ab480c83b6e21998e2e5a177"
      },
      {
        "key": "1942",
        "records": 1,
        "url": "/data/world-war-ii-atlas/sources-by-year/1942.geojson",
        "sha1": "cef74d2bdec443f7e6b6653ce123ff187a18f77b"
      },
      {
        "key": "1944",
        "records": 211,
        "url": "/data/world-war-ii-atlas/sources-by-year/1944.geojson",
        "sha1": "cba08a36794fe2ccaa5f43525b0af66b5a6583d3"
      },
      {
        "key": "1945",
        "records": 209,
        "url": "/data/world-war-ii-atlas/sources-by-year/1945.geojson",
        "sha1": "1b60d07e2558fe45fdc089e56cd3f67bdef7cdbe"
      }
    ],
    "by_theater": [
      {
        "key": "home-fronts",
        "records": 4,
        "url": "/data/world-war-ii-atlas/sources-by-theater/home-fronts.geojson",
        "sha1": "f19be1144d58e64f16f6857df2461160985d237d"
      },
      {
        "key": "western-front",
        "records": 420,
        "url": "/data/world-war-ii-atlas/sources-by-theater/western-front.geojson",
        "sha1": "d7cad02775e9c3d0364defe7a6614c6daf050d52"
      }
    ],
    "by_source": [
      {
        "key": "hyperwar-ibiblio",
        "records": 1,
        "url": "/data/world-war-ii-atlas/sources-by-source/hyperwar-ibiblio.geojson",
        "sha1": "5816e3ab609d183c349c5297872eb4f5faaf2643"
      },
      {
        "key": "loc-twelfth-army-group-1944-07-29",
        "records": 1,
        "url": "/data/world-war-ii-atlas/sources-by-source/loc-twelfth-army-group-1944-07-29.geojson",
        "sha1": "c68fb45eaffb2fd8699510b8cde73b86b8cd02ff"
      },
      {
        "key": "loc-twelfth-army-group-1944-12-11",
        "records": 1,
        "url": "/data/world-war-ii-atlas/sources-by-source/loc-twelfth-army-group-1944-12-11.geojson",
        "sha1": "2ef0d56a8878037aaccdc30170128f32a0cda766"
      },
      {
        "key": "loc-twelfth-army-group-1945-03-09",
        "records": 1,
        "url": "/data/world-war-ii-atlas/sources-by-source/loc-twelfth-army-group-1945-03-09.geojson",
        "sha1": "54c9e1f805a7febc21a20b935ca74ffdce3359e4"
      },
      {
        "key": "loc-ww2-situation-maps",
        "records": 416,
        "url": "/data/world-war-ii-atlas/sources-by-source/loc-ww2-situation-maps.geojson",
        "sha1": "34813235eeac37921903ff6f4eae3423ff26b916"
      },
      {
        "key": "nara-cartographic-ww2",
        "records": 1,
        "url": "/data/world-war-ii-atlas/sources-by-source/nara-cartographic-ww2.geojson",
        "sha1": "80bb2d5cd23103864d7be1c9224f33db11676730"
      },
      {
        "key": "nara-ww2-photos",
        "records": 1,
        "url": "/data/world-war-ii-atlas/sources-by-source/nara-ww2-photos.geojson",
        "sha1": "bbc49cfc83d10ad50ce00285b42311188e5a3b01"
      },
      {
        "key": "truman-library-newsmap",
        "records": 1,
        "url": "/data/world-war-ii-atlas/sources-by-source/truman-library-newsmap.geojson",
        "sha1": "82206971adb70688e5cf3cc0907b0d118e8e6057"
      },
      {
        "key": "ut-pcl-ww2-maps",
        "records": 1,
        "url": "/data/world-war-ii-atlas/sources-by-source/ut-pcl-ww2-maps.geojson",
        "sha1": "dcd51979e0ae5bfddf15d3d6e92e80ccc0328ec9"
      }
    ]
  },
  "loading_policy": {
    "default": "Render source_density first; load source_point chunks only after layer/filter selection.",
    "large_scale_rule": "For more than 5000 records, generate clustered/vector-tile outputs and keep raw source chunks downloadable."
  }
}