How to force gulp to prefix and minify css when it looks for sass changes?

Question

gulp.js

Tell. How to force gulp to prefix and minify css when it looks for sass changes? And then constantly exit watch and run the prefix and then back as not very)

var gulp = require('gulp'),
  sass = require('gulp-sass'),
  autoprefixer = require('gulp-autoprefixer');

gulp.task('sass',function(){
  gulp.src('./sass/*.sass')
    .pipe(sass().on('error', sass.logError))
    .pipe(gulp.dest('./css/'))
})

gulp.task('sass:watch',function(){
  gulp.watch('./sass/*.sass', ['sass'])
})

gulp.task('prefix', () =>
    gulp.src('css/main.css')
        .pipe(autoprefixer({
            browsers: ['last 2 versions', 'ie 11', 'Android >= 4.1', 'Safari >= 8', 'iOS >= 8']
        }))
        .pipe(gulp.dest('css'))
);

Answer 1

gulp.task('sass',function(){
  gulp.src('./sass/*.sass')
    .pipe(sass().on('error', sass.logError))
    .pipe(autoprefixer({
            browsers: ['last 5 versions'],
            cascade: false
        }))
    .pipe(gulp.dest('./css/'))
})

Basic Usage
Configuring and Installing GULP