oliverbooth.dev/Gulpfile.js

const gulp = require('gulp');
const sass = require('gulp-sass')(require('node-sass'));
const cleanCSS = require('gulp-clean-css');
const rename = require('gulp-rename');
const ts = require('gulp-typescript');
const terser = require('gulp-terser');

const srcDir = 'src';
const destDir = 'OliverBooth/wwwroot';

function compileSCSS() {
    return gulp.src(`${srcDir}/scss/**/*.scss`)
        .pipe(sass().on('error', sass.logError))
        .pipe(cleanCSS({ compatibility: 'ie11' }))
        .pipe(rename({ suffix: '.min' }))
        .pipe(gulp.dest(`${destDir}/css`));
}

function compileTS() {
    return gulp.src(`${srcDir}/ts/**/*.ts`)
        .pipe(ts())
        .pipe(terser())
        .pipe(rename({ suffix: '.min' }))
        .pipe(gulp.dest(`${destDir}/js`));
}

function copyJS() {
    return gulp.src(`${srcDir}/ts/**/*.js`)
        .pipe(rename({ suffix: '.min' }))
        .pipe(gulp.dest(`${destDir}/js`));
}

function copyCSS() {
    return gulp.src(`${srcDir}/scss/**/*.css`)
        .pipe(rename({ suffix: '.min' }))
        .pipe(gulp.dest(`${destDir}/css`));
}

function copyImages() {
    return gulp.src(`${srcDir}/img/**/*.*`)
        .pipe(gulp.dest(`${destDir}/img`));
}

exports.default = compileSCSS;
exports.default = gulp.parallel(compileSCSS, compileTS, copyCSS, copyJS, copyImages);