{
 "schemaVersion": "1.0.0",
 "constitutionVersion": "1.0.0",
 "createdAt": "2026-08-12T00:00:00Z",
 "description": "Append-only Evidence Passport records. Old revisions are immutable; corrections create a new revision and preserve the previous permalink.",
 "entity": {
  "type": "project",
  "id": "mainz-digital-twin",
  "title": "Digital Twin Mainz",
  "canonicalUrl": "https://1001smartcities.org/projects/mainz-digital-twin/"
 },
 "currentRevisionId": "2026-08-22-evidence-baseline",
 "revisions": [
  {
   "id": "2026-08-22-evidence-baseline",
   "createdAt": "2026-08-22T09:10:00Z",
   "effectiveAt": "2026-08-02",
   "changeType": "baseline",
   "summary": "Created the first structured Evidence Passport with 7 claims and 3 source dossiers.",
   "preparedBy": {
    "type": "automation",
    "label": "AI-assisted evidence preparation",
    "humanApproved": false
   },
   "review": {
    "status": "unreviewed",
    "by": null,
    "date": null,
    "note": "Awaiting operator and domain-expert review; publication of this revision implies neither."
   },
   "changes": [
    {
     "operation": "add",
     "path": "/evidencePassport",
     "summary": "Added claim-level evidence mapping and source dossiers."
    },
    {
     "operation": "add",
     "path": "/revisionHistory",
     "summary": "Established a permanent, hash-addressed baseline revision."
    }
   ],
   "snapshotHash": "sha256:0a19594cd1885e531ef695bfdebc1ec7cc4c7244e0e5e36e07984356fee38b7e",
   "snapshot": {
    "asOf": "2026-08-02",
    "projectFingerprint": "sha256:b93444823da8124b4891937abc284d81c7e05394bff599b847bba1bf8431059f",
    "assurance": {
     "status": "unreviewed",
     "scope": "evidence-passport-revision",
     "statement": "AI-assisted structural preparation. This revision has not been reviewed by a human or subject-matter expert.",
     "machineChecks": [
      "schema",
      "publication-diff-contract",
      "material-project-fingerprint",
      "claim-text-drift",
      "source-reference-resolution",
      "complete-source-dossier",
      "snapshot-hash"
     ]
    },
    "projectState": {
     "status": "construction",
     "outcome": "ongoing",
     "evidenceGrade": "official",
     "timeline": {
      "started": 2025,
      "ended": null
     }
    },
    "governance": {
     "operator": null,
     "actorTypes": [
      "city-government"
     ],
     "fundingModel": "public",
     "fundingDescription": null,
     "cost": null,
     "ownership": null,
     "decisionRights": null,
     "exitConditions": null
    },
    "claims": [
     {
      "id": "clm-d7ad9d5d99a1bafc",
      "field": "snippet",
      "text": "As part of its mainzDIGITAL strategy",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-44e3f04c651c9cdf"
      ],
      "supportNote": "The city's own report to the council is titled „Sachstandsbericht zur Digitalisierungsstrategie mainzDIGITAL der Landeshauptstadt Mainz“, and the digital twin is described inside it as one of the strategy's projects: „Der Konzern Stadt Mainz plant zunächst die Entwicklung eines Digitalen Zwillings“. The same passage ties it to the geodata work — „Das Vorhaben ist eng mit dem Relaunch des WebGIS-Systems verknüpft“ (the undertaking is closely linked to the relaunch of the WebGIS system) — and the report states that mainzDIGITAL supports such projects with facilitation and coordination.",
      "caveat": "Neither the March 2026 supplier release nor the local press report names mainzDIGITAL. The link between the strategy and the geodata relaunch rests on the city's own status report of April 2025.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-3ae6db2022e18375",
      "field": "snippet",
      "text": "Mainz is modernising its geodata infrastructure",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-a01ada656eb066eb",
       "src-1339bbff11641e70"
      ],
      "supportNote": "Merkurist reports „Die Stadt Mainz hat den Relaunch ihrer digitalen Geodatenplattform gestartet“ and „Mit dem Projekt wird das aktuelle System grundlegend modernisiert und an aktuelle technische Anforderungen angepasst“ (the existing system is being fundamentally modernised and brought up to current technical requirements). The VertiGIS release describes the same undertaking: the city and its municipal data centre KDZ „setzen beim Relaunch ihrer Geodateninfrastruktur (GDI) auf VertiGIS und Esri Deutschland“.",
      "caveat": null,
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-083d096c0c8e3b8c",
      "field": "snippet",
      "text": "a cloud-based platform",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-1339bbff11641e70"
      ],
      "supportNote": "The VertiGIS release states the goal is „der Aufbau einer modernen, cloudbasierten und sicherheitszertifizierten SaaS-Plattform“ (a modern, cloud-based and security-certified SaaS platform) and that the technical basis is Esri's ArcGIS Online, which „ohne lokale Server auskommt“ (needs no local servers).",
      "caveat": "The cloud architecture is described only in the supplier's own release. The city's status report and the local press coverage report the relaunch without detailing how it is hosted.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-eb61a573b4732296",
      "field": "snippet",
      "text": "built with Esri and VertiGIS",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-1339bbff11641e70",
       "src-a01ada656eb066eb"
      ],
      "supportNote": "The VertiGIS release names the components: „Die technische Basis bildet ArcGIS Online von Esri“, extended by „VertiGIS Studio, VertiGIS FM sowie weitere Komponenten der VertiGIS Neo Technologievision“. Merkurist states the same independently: „Für die Umsetzung arbeitet die Stadt mit den Partnern Esri Deutschland GmbH und VertiGIS GmbH zusammen“.",
      "caveat": "Esri and VertiGIS are the suppliers. The platform is run by the city of Mainz together with its own municipal data centre, the Eigenbetrieb Kommunale Datenzentrale (KDZ).",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-4aff0666f1624932",
      "field": "snippet",
      "text": "whose relaunch began in March 2026",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-a01ada656eb066eb",
       "src-1339bbff11641e70"
      ],
      "supportNote": "Merkurist, published 21 March 2026, reports that the relaunch had begun and that the city announced it on the Friday before: „Die Stadt Mainz hat den Relaunch ihrer digitalen Geodatenplattform gestartet. Das teilte die Stadt am Freitag mit.“ The VertiGIS release of 25 March 2026 announces the same relaunch and carries a photograph of the contract for it being signed. Neither source describes the platform as arriving in stages; the only phased schedule in the listed sources is in the city's April 2025 report and concerns the digital twin itself: „Geplant ist eine schrittweise Umsetzung über fünf Jahre“.",
      "caveat": "The sources date the start of the relaunch to March 2026 but do not describe the platform as arriving in stages. The five-year step-by-step schedule in the city's April 2025 report is a plan for the digital twin, not a record of how this platform was delivered.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-ec7924065026d41c",
      "field": "snippet",
      "text": "which the city calls the foundation for a future digital twin",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-1339bbff11641e70",
       "src-a01ada656eb066eb",
       "src-44e3f04c651c9cdf"
      ],
      "supportNote": "Both March 2026 sources carry the same quote from mayor Nino Haase: „Der Aufbau einer modernen Geodateninfrastruktur ist die Grundlage für den digitalen Zwilling unserer Stadt“ (building a modern geodata infrastructure is the foundation for our city's digital twin). That the twin is still ahead is confirmed by the city's own April 2025 report: „Der Konzern Stadt Mainz plant zunächst die Entwicklung eines Digitalen Zwillings“, with only a prototype built — „Der erste Prototyp wurde bereits entwickelt“ — and a feasibility study on costs and value commissioned in December 2024 and, at the time of the report, not yet complete.",
      "caveat": "This is the mayor's own framing, and the entry reports it as such. On the record of these sources the twin itself exists as a prototype and a commissioned feasibility study, not as a system in operation.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-6a533921efe72d42",
      "field": "snippet",
      "text": "to help plan traffic, climate and social infrastructure",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-1339bbff11641e70",
       "src-a01ada656eb066eb"
      ],
      "supportNote": "The mayor's quote continues: „schaffen wir die Basis für bessere Planungsentscheidungen – etwa in den Bereichen Verkehr, Klima oder soziale Infrastruktur“ (we create the basis for better planning decisions — in areas such as traffic, climate or social infrastructure). Merkurist paraphrases the same three fields: „Dies betreffe etwa die Bereiche Verkehr, Klima oder soziale Infrastruktur“.",
      "caveat": "These are the stated purposes of the platform. Neither source reports a planning decision that has been taken with it.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     }
    ],
    "sources": [
     {
      "id": "src-44e3f04c651c9cdf",
      "title": "Landeshauptstadt Mainz – mainzDIGITAL Sachstandsbericht (authority)",
      "url": "https://www.mainz.de/medien/internet/downloads/mainzDIGITAL-Sachstandsbericht_April-2025.pdf",
      "publisher": {
       "name": null,
       "domain": "mainz.de",
       "classification": "not-classified"
      },
      "sourceType": "pdf",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-d7ad9d5d99a1bafc",
       "clm-ec7924065026d41c"
      ],
      "temporal": {
       "publishedAt": null,
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-08-02",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "record-date-only"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Official status report on the digitalisation strategy, April 2025.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-1339bbff11641e70",
      "title": "VertiGIS (partner, press release)",
      "url": "https://www.vertigis.com/de/news/cloud-first-strategie-fur-die-verwaltung-mainz-implementiert-vollstandig-cloudbasierte-gdi-mit-vertigis-und-esri/",
      "publisher": {
       "name": null,
       "domain": "vertigis.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-3ae6db2022e18375",
       "clm-083d096c0c8e3b8c",
       "clm-eb61a573b4732296",
       "clm-4aff0666f1624932",
       "clm-ec7924065026d41c",
       "clm-6a533921efe72d42"
      ],
      "temporal": {
       "publishedAt": "2026-03-25",
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-08-02",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Vendor press release, 25 March 2026, confirming the cloud geodata-platform relaunch and the mayor's 'foundation for the digital twin' framing.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     },
     {
      "id": "src-a01ada656eb066eb",
      "title": "Merkurist Mainz (press)",
      "url": "https://merkurist.de/mainz/geodatenplattform-was-der-neue-digitale-zwilling-fuer-die-stadt-mainz-bedeutet_V6AU?SSOC=1",
      "publisher": {
       "name": null,
       "domain": "merkurist.de",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
       "clm-3ae6db2022e18375",
       "clm-eb61a573b4732296",
       "clm-4aff0666f1624932",
       "clm-ec7924065026d41c",
       "clm-6a533921efe72d42"
      ],
      "temporal": {
       "publishedAt": "2026-03-21",
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-08-02",
       "dossierCreatedAt": "2026-08-22",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Local press coverage of the geodata platform relaunch and its stated purpose.",
       "exact": false
      },
      "preservation": {
       "archiveUrl": null,
       "archivedAt": null,
       "contentHash": null,
       "status": "not-captured"
      }
     }
    ],
    "coverage": {
     "claimsTotal": 7,
     "claimsMapped": 7,
     "sourcesTotal": 3,
     "sourcesUsedByClaims": 3,
     "sourcesWithPublicationDate": 2,
     "sourcesWithArchive": 0,
     "sourcesWithExactLocator": 0,
     "sourcesWithContentHash": 0
    },
    "limits": [
     "Publisher names and source languages have not yet been classified; domains are recorded without guessing.",
     "Existing source notes are descriptive locators, not page- or paragraph-exact citations.",
     "A missing archive, publication date or content hash is shown as null rather than inferred.",
     "The project-level evidence grade ranks the strongest source in the entry; it is not a truth score for every claim."
    ]
   }
  }
 ]
}