Why doesn't @import work (gives an error) in gulp-stylus?

Question

Preprocessors

Doesn't work either via stylus API:

gulp.task('build:style', function (done) {
    gulp.src(path.app.style)
        //some pipe
        .pipe(stylus({
            import: ['app/blocks/common/mixins.styl'], 
            compress: true,
            'include css': true
        }))
        //some pipe
        .pipe(gulp.dest(path.build.style))
    done();
});

Not via the @ import directive in *.styl files directly.
Gives "failed to locate @ import fapp/blocks/common/mixins.styl"
It doesn't matter if the path is relative or absolute.
What am I doing wrong?
PS
There is no stylus tag...

Answer 1

So far I've found this workaround.
We collect all the files and do the concatenation.
The connection order in scr is important.
Because if you do not specify mixins ahead, then they may not be available.

gulp.src(['app/blocks/common/mixins.styl', 'app/blocks/**/*.styl'])
        .pipe(sourcemap.init())
        .pipe(concat('app.styl'))
        .pipe(stylus({
            compress: true,
            'include css': true
        }))
        //some pipe