function write_zip(cfb/*:CFBContainer*/, options/*:CFBWriteOpts*/)/*:RawBytes*/ {
	var _opts = options || {};
	var out = [], cdirs = [];
	var o/*:CFBlob*/ = new_buf(1);
	var method = (_opts.compression ? 8 : 0), flags = 0;
	var desc = false;
	if(desc) flags |= 8;
	var i = 0, j = 0;

	var start_cd = 0, fcnt = 0;
	var root = cfb.FullPaths[0], fp = root, fi = cfb.FileIndex[0];
	var crcs = [];
	var sz_cd = 0;

	for(i = 1; i < cfb.FullPaths.length; ++i) {
		fp = cfb.FullPaths[i].slice(root.length); fi = cfb.FileIndex[i];
		if(!fi.size || !fi.content || fp == "\u0001Sh33tJ5") continue;
		var start = start_cd;

		/* TODO: CP437 filename */
		var namebuf = new_buf(fp.length);
		for(j = 0; j < fp.length; ++j) namebuf.write_shift(1, fp.charCodeAt(j) & 0x7F);
		namebuf = namebuf.slice(0, namebuf.l);
		crcs[fcnt] = CRC32.buf(/*::((*/fi.content/*::||[]):any)*/, 0);

		var outbuf = fi.content/*::||[]*/;
		if(method == 8) outbuf = _deflateRawSync(outbuf);

		/* local file header */
		o = new_buf(30);
		o.write_shift(4, 0x04034b50);
		o.write_shift(2, 20);
		o.write_shift(2, flags);
		o.write_shift(2, method);
		/* TODO: last mod file time/date */
		if(fi.mt) write_dos_date(o, fi.mt);
		else o.write_shift(4, 0);
		o.write_shift(-4, (flags & 8) ? 0 : crcs[fcnt]);
		o.write_shift(4,  (flags & 8) ? 0 : outbuf.length);
		o.write_shift(4,  (flags & 8) ? 0 : /*::(*/fi.content/*::||[])*/.length);
		o.write_shift(2, namebuf.length);
		o.write_shift(2, 0);

		start_cd += o.length;
		out.push(o);
		start_cd += namebuf.length;
		out.push(namebuf);

		/* TODO: encryption header ? */
		start_cd += outbuf.length;
		out.push(outbuf);

		/* data descriptor */
		if(flags & 8) {
			o = new_buf(12);
			o.write_shift(-4, crcs[fcnt]);
			o.write_shift(4, outbuf.length);
			o.write_shift(4, /*::(*/fi.content/*::||[])*/.length);
			start_cd += o.l;
			out.push(o);
		}

		/* central directory */
		o = new_buf(46);
		o.write_shift(4, 0x02014b50);
		o.write_shift(2, 0);
		o.write_shift(2, 20);
		o.write_shift(2, flags);
		o.write_shift(2, method);
		o.write_shift(4, 0); /* TODO: last mod file time/date */
		o.write_shift(-4, crcs[fcnt]);

		o.write_shift(4, outbuf.length);
		o.write_shift(4, /*::(*/fi.content/*::||[])*/.length);
		o.write_shift(2, namebuf.length);
		o.write_shift(2, 0);
		o.write_shift(2, 0);
		o.write_shift(2, 0);
		o.write_shift(2, 0);
		o.write_shift(4, 0);
		o.write_shift(4, start);

		sz_cd += o.l;
		cdirs.push(o);
		sz_cd += namebuf.length;
		cdirs.push(namebuf);
		++fcnt;
	}

	/* end of central directory */
	o = new_buf(22);
	o.write_shift(4, 0x06054b50);
	o.write_shift(2, 0);
	o.write_shift(2, 0);
	o.write_shift(2, fcnt);
	o.write_shift(2, fcnt);
	o.write_shift(4, sz_cd);
	o.write_shift(4, start_cd);
	o.write_shift(2, 0);

	return bconcat(([bconcat((out/*:any*/)), bconcat(cdirs), o]/*:any*/));
}