gulpfile.js

var gulp = require("gulp");
var replace = require("gulp-replace");
var fs = require("fs");

const OUT_LIB = "lib";

function updateVersion(dst, file) {

  const VERSION = JSON.parse(fs.readFileSync("./package.json")).version;

  return gulp.src(dst + "/" + file)
    .pipe(replace("CONFIGCAT_SDK_VERSION", VERSION))
    .pipe(gulp.dest(dst));
}

function updateVersion_lib() {
  return updateVersion(OUT_LIB, "version.js");
}

exports.default = gulp.series(
  gulp.parallel(updateVersion_lib));