Revenue from contracts with customers (Tables)

12 Months Ended

Dec. 31, 2022

Revenue from Contract with Customer [Abstract]

Disaggregation of revenue

The following table depicts the disaggregation of revenue by type of products or services and timing of transfer of products or services (in thousands):

	Year ended December 31,
	2022		2021		2020
Type of products or services
QCaaS	$	5,616	$	4,424	$	4,313
Professional services	1,478		1,786		426
Other revenue	79		69		421
Total revenue, net	$	7,173	$	6,279	$	5,160
Timing of revenue recognition
Revenue recognized over the time	$	6,960	$	6,090	$	4,688
Revenue recognized at a point in time	213		189		472
Total revenue, net	$	7,173	$	6,279	$	5,160

The following table presents a summary of revenue by geography for the years ended December 31, 2022, 2021 and 2020:

	Years ended December 31,
	2022		2021		2020
United States	$	3,342	$	3,425	$	3,119
Japan	1,241		1,614		1,630
Germany	1,150		741		155
Other	1,440		499		256
Total revenue	$	7,173	$	6,279	$	5,160

Accounts receivable, contract assets and liabilities, and changes in deferred revenue

The following table provides information about account receivable, contract assets and liabilities as of December 31, 2022 and December 31, 2021 (in thousands):

	December 31,		December 31,
	2022		2021
Contract assets:
Trade account receivable	$	757	$	421
Unbilled receivables, which are included in 'Prepaid expenses and other current assets'	58		17
Total contract assets	815		438
Contract liabilities:
Deferred revenue, current	1,781		2,665
Deferred revenue, noncurrent	9		54
Customer deposit, which are included in 'Accrued expenses and other current liabilities'	45		21
Total contract liabilities	$	1,835	$	2,740

Changes in deferred revenue from contracts with customers were as follows (in thousands):

	December 31,		December 31,
	2022		2021
Balance at beginning of period	$	2,719	$	4,713
Deferral of revenue	5,325		4,092
Recognition of deferred revenue	(6,254)		(6,086)
Balance at end of period	$	1,790	$	2,719