CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 30, 2019	Mar. 31, 2018	Dec. 29, 2018
Cash flows from operating activities:
Net loss	$ (6,895)	$ (4,901)	$ 23,800
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	245	166
Stock-based compensation expense	57	27
Change in fair value of preferred stock warrant liability	(273)	30
Non-cash interest expense	115	60
Net amortization of premiums on marketable securities		9
Unrealized foreign currency transaction (gains) losses	160	(143)
Changes in operating assets and liabilities:
Accounts receivable	(1,746)	(1,021)
Inventory	(2,468)	(1,178)
Prepaid expenses and other current assets	417	(143)
Accounts payable	758	(843)
Accrued expenses and other current liabilities	2,394	1,692
Deferred revenue	57	(4)
Deferred rent	(87)	(82)
Net cash used in operating activities	(7,266)	(6,331)
Cash flows from investing activities:
Purchases of property and equipment	(3)	(40)
Proceeds from sales and maturities of marketable securities		5,000
Net cash provided by (used in) investing activities	(3)	4,960
Cash flows from financing activities:
Repayments of long-term debt		(892)
Payments of initial public offering costs	(705)
Proceeds from issuance of common stock upon exercise of stock options	8	12
Net cash used in financing activities	(697)	(880)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(60)	114
Net decrease in cash, cash equivalents and restricted cash	(8,026)	(2,137)
Cash, cash equivalents and restricted cash, beginning of period	20,741	12,436
Cash, cash equivalents and restricted cash, end of period	12,715	10,299	$ 20,741
Supplemental disclosure of non-cash investing and financing activities:
Transfers of inventory to property and equipment	407	342
Purchases of property and equipment included in accounts payable	129	$ 4
Deferred offering costs included in accounts payable and accrued expenses	$ 1,134