semver()

Creates a validator that accepts strict semver strings.

Signature

function semver(): SemverValidator

Accepted Values

Accepts semantic version strings in X.Y.Z format. No v prefix, no ranges (^, ~). Supports optional pre-release tags and build metadata.

Input	Result
"1.0.0"	✅ "1.0.0"
"0.0.1"	✅ "0.0.1"
"999.999.999"	✅ "999.999.999"
"1.2.3-alpha"	✅ "1.2.3-alpha"
"1.2.3-alpha.1"	✅ "1.2.3-alpha.1"
"1.2.3+build.1"	✅ "1.2.3+build.1"
"1.2.3-rc.1+build.2"	✅ "1.2.3-rc.1+build.2"
"v1.0.0"	❌ Invalid — v prefix not allowed
"1.0"	❌ Invalid — must have three parts
"^1.0.0"	❌ Invalid — range not allowed
"abc"	❌ Type error — not a semver string

Refinements

semver() has no type-specific refinements. It supports only the chainable methods (.optional(), .default(), .describe(), .secret(), .validate()).

Examples

Basic semver

const env = defineEnv({
  APP_VERSION: semver(),
})
// env.APP_VERSION: string

With defaults

const env = defineEnv({
  API_VERSION: semver().default("1.0.0"),
})
// env.API_VERSION: string (default: "1.0.0")

Optional

const env = defineEnv({
  SCHEMA_VERSION: semver().optional(),
})
// env.SCHEMA_VERSION: string | undefined