Versioning Protocols Calver Structure

Calendar Versioning (CalVer) version string using date-based identifiers

Type: object Properties: 7 Required: 2

API DesignBackward CompatibilitySoftware DevelopmentVersion ControlSemantic VersioningAPI LifecycleDeprecation

CalendarVersion is a JSON Structure definition published by Versioning Protocols, describing 7 properties, of which 2 are required. It conforms to the https://json-structure.org/meta/core/v0/# meta-schema.

Properties

version year month day modifier format releaseDate

Meta-schema: https://json-structure.org/meta/core/v0/#

JSON Structure

{
  "$schema": "https://json-structure.org/meta/core/v0/#",
  "$id": "https://raw.githubusercontent.com/api-evangelist/versioning-protocols/refs/heads/main/json-structure/versioning-protocols-calver-structure.json",
  "description": "Calendar Versioning (CalVer) version string using date-based identifiers",
  "type": "object",
  "properties": {
    "version": {
      "type": "string",
      "description": "Full CalVer version string (e.g., 2026-05-03, 2026.05)",
      "example": "2026-05-03"
    },
    "year": {
      "type": "int32",
      "minimum": 2000,
      "description": "Full 4-digit year",
      "example": 2026
    },
    "month": {
      "type": "int32",
      "minimum": 1,
      "maximum": 12,
      "description": "Month number (1-12)",
      "example": 5
    },
    "day": {
      "type": "int32",
      "minimum": 1,
      "maximum": 31,
      "description": "Day of month (1-31)",
      "example": 3
    },
    "modifier": {
      "type": "string",
      "description": "Optional modifier (e.g., dev, alpha, beta, rc)",
      "example": "rc"
    },
    "format": {
      "type": "string",
      "enum": [
        "YYYY.MM.DD",
        "YYYY-MM-DD",
        "YYYY.MM",
        "YYYY"
      ],
      "description": "CalVer format used for this version",
      "example": "YYYY-MM-DD"
    },
    "releaseDate": {
      "type": "date",
      "description": "ISO 8601 release date",
      "example": "2026-05-03"
    }
  },
  "required": [
    "version",
    "year"
  ],
  "name": "CalendarVersion"
}

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