improving the base package.json for less & autoprefixer preprocessing on Business Catalyst sites

gulpfile.js

var gulp = require('gulp'),
    path = require('path'),
    sftp = require('gulp-sftp'),
    less = require('gulp-less'),
    sourcemaps = require('gulp-sourcemaps'),
    autoprefixer = require('gulp-autoprefixer'),
    rename = require('gulp-rename'),
    browserSync = require('browser-sync');

var setup = {
    siteDomain: 'test-incontextediting.worldsecuresystems.com',
    pathToMainLessFile: "assets/less/", // include the trailing forward slash
    mainLessFileName: "central", //.less is implied; leave it out
    lessOptions = {
        compress: true
    }
};
setup.lessFileWithPath = path.join(setup.pathToMainLessFile, setup.mainLessFileName);
setup.outputPath = setup.pathToMainLessFile;

// NOTE: `.less` files that aren't in `setup.pathToMainLessFile` won't be
// watched by the less compiler.

// NOTE: All generated files will be uploaded to the path `setup.outputPath`
// on the remote.
// TODO: Upload generated files to the same remote path as the local path (relative
// to project root)

var homedir = (process.platform === 'win32' || process.platform === 'win64') ? process.env.HOMEPATH : process.env.HOME;
var credentials = require(path.join(homedir, 'bc-credentials.json'));

setup.remoteHost = {
    host: setup.siteDomain,
    port: 22,
    user: setup.siteDomain + '/' + credentials.user,
    pass: credentials.pass,
    remotePath: '/' + setup.outputPath
};

var dontWatchFoldersRE = /node_modules/i;

var browserSyncTask = function() {
    browserSync({
        // TODO: find a better way to exclude folders like `node_modules`
        // and `.git`. This may be a good starting point:
        // https://github.com/shama/gaze/issues/109
        // FIXME: Watcher is currently limited to 4 levels depth, for
        // startup performance.
        files : [

        '*.css',
        '*.html',
        '*.htm',
        '*.js',

        '*/*.css',
        '*/*.html',
        '*/*.htm',
        '*/*.js',

        '*/*/*.css',
        '*/*/*.html',
        '*/*/*.htm',
        '*/*/*.js',

        '*/*/*/*.css',
        '*/*/*/*.html',
        '*/*/*/*.htm',
        '*/*/*/*.js',

        '*/*/*/*/*.css',
        '*/*/*/*/*.html',
        '*/*/*/*/*.htm',
        '*/*/*/*/*.js'

        ],
        watchOptions: {
            // WHY wasn't `filter` documented in browser-sync or gaze???
            filter: function(srcPath, opts) {
                var isMatch = !dontWatchFoldersRE.test(srcPath);
                //process.stdout.write(isMatch ? 'T' : '.');
                return isMatch;
            }
        },
        port: 3001,
        proxy: setup.siteDomain,
        reloadDelay: 5000,
        open: false,
        minify: false
    });
}

var buildLess = function() {
    return gulp.src(setup.lessFileWithPath + '.less')
        .pipe(sourcemaps.init())
        .pipe(less(setup.lessOptions))
        .pipe(autoprefixer())
        .pipe(rename({extname:'.min.prefixed.css'}))
        .pipe(sourcemaps.write('./'))
        .pipe(gulp.dest(setup.outputPath));
}

var buildAndUpload = function() {
    // TODO: reduce repetition by extending `buildLess()`
    // FIXME: keep the SSH connection alive & reusable
    return gulp.src(setup.lessFileWithPath + '.less')
        .pipe(sourcemaps.init())
        .pipe(less(setup.lessOptions))
        .pipe(autoprefixer())
        .pipe(rename({extname:'.min.prefixed.css'}))
        .pipe(sourcemaps.write('./'))
        .pipe(gulp.dest(setup.outputPath))
        .pipe(sftp(setup.remoteHost));
}

gulp.task('build-less', buildLess);

gulp.task('build-and-upload', buildAndUpload);

gulp.task('watch', function() {
    gulp.watch(
        setup.pathToMainLessFile + '*.less',
        ['build-and-upload']
    );
});

gulp.task('browser-sync', browserSyncTask);

gulp.task('default', [
    'watch',
    'browser-sync'
]);

package.json

{
  "//": [
    "Packages used for less & autoprefixer preprocessing on Business Catalyst sites",
    "Replace SITE-NAME-HERE with your site name if you feel like it; it's not used anywhere (yet)"
  ],
  "name": "SITE-NAME-HERE",
  "version": "0.0.1",
  "description": "",
  "main": "gruntfile.js",
  "dependencies": {},
  "devDependencies": {
    "browser-sync": "^1.9.1",
    "gulp": "^3.8.10",
    "gulp-autoprefixer": "^2.1.0",
    "gulp-less": "^2.0.1",
    "gulp-rename": "^1.2.0",
    "gulp-sftp": "^0.1.4",
    "gulp-sourcemaps": "^1.3.0"
  },
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "repository": {
    "type": "git",
    "url": "x:\\\\git-repos\\\\SITE-NAME-HERE\\\\"
  },
  "author": "",
  "license": "ISC"
}

Have you determined how to keep the sftp connection alive? I haven't dug into the gulp-sftp source yet, but it seems it may be explicitly closing the connection after all uploads have completed.