Versioning reference

Versioning allows you to deterministically control the precise revisions of dependencies used by your project from within your manifest file. Versioning is only available to Manifest mode users.

For more information about the vcpkg versioning algorithm and high level concepts, see Versioning Concepts.

For an example with context, see our guide to getting started with versioning.

Version Schemes

Ports in vcpkg should attempt to follow the versioning conventions used by the package's authors. For that reason, when declaring a package's version the appropriate scheme should be used.

Each versioning scheme defines its own rules on what is a valid version string and more importantly the rules for how to sort versions using the same scheme.

The versioning schemes understood by vcpkg are:

Manifest property Versioning scheme
version For dot-separated numeric versions
version-semver For SemVer compliant versions
version-date For dates in the format YYYY-MM-DD
version-string For arbitrary strings

A manifest must contain only one version declaration.


By design, vcpkg does not compare versions that use different schemes. For example, a package that has a version-string: 7.1.3 cannot be compared with the same package using version: 7.1.4, even if the conversion seems obvious.


Accepts version strings that follow a relaxed, dot-separated-, semver-like scheme.

The version is logically composed of dot-separated (.) numeric sections. Each section must contain an integer positive number with no leading zeroes.

The regex pattern for this versioning scheme is: (0|[1-9]\d*)(\.(0|[1-9]\d*))*

Sorting behavior: When comparing two versions, each section is compared from left to right by their numeric value, until the first difference is found. A version with the smallest set of sections takes precedence over another with a larger set of sections, given that all their preceding sections compare equally.


0 < 0.1 < 0.1.0 < 1 < 1.0.0 < 1.0.1 < 1.1< 2.0.0


Accepts version strings that follow semantic versioning conventions as described in the semantic versioning specification.

Sorting behavior: Strings are sorted following the rules described in the semantic versioning specification.


1.0.0-1 < 1.0.0-alpha < 1.0.0-beta < 1.0.0 < 1.0.1 < 1.1.0


Accepts version strings that can be parsed to a date following the ISO-8601 format YYYY-MM-DD. Disambiguation identifiers are allowed in the form of dot-separated-, positive-, integer-numbers with no leading zeroes.

This is the recommended versioning scheme for "Live at HEAD" libraries that don't have established release versions.

The regex pattern for this versioning scheme is: \d{4}-\d{2}-\d{2}(\.(0|[1-9]\d*))*

Sorting behavior: Strings are sorted first by their date part, then by numeric comparison of their disambiguation identifiers. Disambiguation identifiers follow the rules of the relaxed (version) scheme.

Examples: 2021-01-01 < 2021-01-01.1 < 2021-02-01.1.2 < 2021-02-01.1.3 < 2021-02-01


For packages using version strings that do not fit any of the other schemes, it accepts most arbitrary strings. The # which is used to denote port versions is disallowed.

Sorting behavior: No sorting is attempted on the version string itself. However, if the strings match exactly, their port versions can be compared and sorted.


  • apple <> orange <> orange.2 <> orange2
  • watermelon#0< watermelon#1


Port-versions track changes in the packaging files (vcpkg.json, portfile.cmake, etc) without any changes to the upstream library version.

A port version is a non-negative integer value.

The rules for port versions are:

  • Start at 0 for the original version of the port,
  • increase by 1 each time a vcpkg-specific change is made to the port that does not increase the version of the package,
  • and reset to 0 each time the version of the package is updated.


vcpkg follows the text format <version>#<port version>. For example 1.2.0#2 means version 1.2.0 port version 2. If the port version is 0 the #0 suffix is omitted (e.g., 1.2.0 implies version 1.2.0 port version 0).

Sorting behavior: If two versions compare equally, their port versions are compared by their numeric value, lower port versions take precedence.


  • 1.2.0 < 1.2.0#1 < 1.2.0#2 < 1.2.0#10
  • 2021-01-01#20 < 2021-01-01.1
  • windows#7 < windows#8

Version Constraints


Baselines define a global version floor for what versions will be considered. This enables top-level manifests to keep the entire graph of dependencies up-to-date without needing to individually specify direct "version>=" constraints.

Every configured registry has an associated baseline. For manifests that don't configure any registries, the "builtin-baseline" field defines the baseline for the built-in registry. If a manifest does not configure any registries and does not have a "builtin-baseline", the install operates according to the Classic mode algorithm and ignores all versioning information.

Baselines, like other registry settings, are ignored from ports consumed as a dependency. If a minimum version is required during transitive version resolution the port should use "version>=".


  "name": "project",
  "version": "1.0.0",
  "dependencies": ["zlib", "fmt"],

To add an initial "builtin-baseline", use vcpkg x-update-baseline --add-initial-baseline. To update baselines in a manifest, use vcpkg x-update-baseline.


Expresses a minimum version requirement, version>= declarations put a lower boundary on the versions that can be used to satisfy a dependency.


vcpkg selects the lowest version that matches all constraints, so a less-than constraint is not required.


  "name": "project",
  "version-semver": "1.0.0",
  "dependencies": [
    { "name": "zlib", "version>=": "1.2.11#9" },
    { "name": "fmt", "version>=": "7.1.3#1" }

As part of a version constraint declaration, a port version can be specified by adding the suffix #<port-version>, in the previous example 1.2.11#9 refers to version 1.2.11 port version 9.


Declaring an override forces vcpkg to ignore all other version constraints and use the version specified in the override. This is useful for pinning exact versions and for resolving version conflicts.

Overrides are declared as an array of package version declarations.

For an override to take effect, the overridden package must form part of the dependency graph. That means that a dependency must be declared either by the top-level manifest or be part of a transitive dependency.

  "name": "project",
  "version-semver": "1.0.0",
  "dependencies": [
    { "name": "zlib", "version>=": "1.2.11#9" },
  "overrides": [
    { "name": "fmt", "version": "6.0.0" },
    { "name": "openssl", "version-string": "1.1.1h#3" }