diff --git a/plugin/docker.go b/plugin/docker.go
index cb38fb2..1cd30b1 100644
--- a/plugin/docker.go
+++ b/plugin/docker.go
@@ -5,6 +5,7 @@ import (
 	"os"
 	"os/exec"
 	"strings"
+	"time"
 
 	"github.com/urfave/cli/v2"
 )
@@ -106,7 +107,11 @@ func commandBuild(build Build) *exec.Cmd {
 		args = append(args, "--platform", strings.Join(build.Platforms.Value()[:], ","))
 	}
 
-	return exec.Command(dockerExe, args...)
+	cmd := exec.Command(dockerExe, args...)
+	copy(os.Environ(), cmd.Env)
+	cmd.Env = append(cmd.Env, fmt.Sprintf("DRONE_DOCKER_BUILD_TIME=%s", time.Now().Format(time.RFC3339)))
+
+	return cmd
 }
 
 // helper function to add proxy values from the environment