Jenkins Declarative Pipeline and Groovy ZonedDateTime for Regional Timestamp Conversion

Answer the question first

In a Declarative Pipeline you can read the build’s start time directly from the currentBuild object. The value currentBuild.startTimeInMillis is an epoch‑millisecond timestamp that is independent of the agent’s local clock. From that timestamp you can create a java.time.Instant and then apply any ZoneId you need.

Step 1 – Grab the raw start time

def startMillis = currentBuild.startTimeInMillis

This returns the exact moment the build was queued, in UTC milliseconds since the epoch.

Step 2 – Convert to an Instant or ZonedDateTime

import java.time.*
import java.time.format.*

// Option A – keep it as an Instant
Instant buildInstant = Instant.ofEpochMilli(startMillis)

// Option B – immediately create a ZonedDateTime in the target zone
ZoneId targetZone = ZoneId.of('America/New_York')
ZonedDateTime buildInNY = buildInstant.atZone(targetZone)

Step 3 – Format the timestamp for reporting

String formatted = buildInNY.format(DateTimeFormatter.ofPattern('yyyy-MM-dd HH:mm:ss z'))
echo "Build started at ${formatted}"

The z pattern token includes the IANA zone abbreviation (e.g., "EDT" or "EST"). If you prefer the numeric offset, use XXX instead.

Full Declarative Pipeline example

pipeline {
    agent any
    stages {
        stage('Show Build Time') {
            steps {
                script {
                    import java.time.*
                    import java.time.format.*
                    def startMillis = currentBuild.startTimeInMillis
                    ZoneId nyZone = ZoneId.of('America/New_York')
                    ZonedDateTime startNY = Instant.ofEpochMilli(startMillis).atZone(nyZone)
                    String fmt = startNY.format(DateTimeFormatter.ofPattern('yyyy-MM-dd HH:mm:ss z'))
                    echo "Build started at ${fmt}"
                }
            }
        }
    }
}

Things to keep in mind

• Jenkins must be running on Java 8 or newer – the java.time API is not available on older Java runtimes.
• Use a valid IANA zone ID (e.g., America/New_York, Europe/London). An invalid ID throws an IllegalArgumentException.
• Because ZonedDateTime and Instant are serializable, you usually don’t need @NonCPS, but if you perform heavy processing inside a script block consider adding it to avoid CPS serialization issues.
• For downstream consumption you can store the formatted string in an environment variable:

  env.BUILD_START_NY = fmt
  

Ask for missing detail

If you need a different target zone than the example, just replace ZoneId.of('America/New_York') with the desired IANA ID.