Stock-based compensation (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Schedule of Stock-based Compensation

The Company recognized stock-based compensation for all stock options in the statements of operations and comprehensive loss as follows (in thousands):

	Year Ended December 31,
	2021		2020		2019
Cost of revenue	$	637	$	657	$	58
Research and development		7,240		6,059		621
Sales and marketing		3,823		640		140
General and administrative		13,663		4,701		474
Total stock-based compensation	$	25,363	$	12,057	$	1,293

Schedule of Stock Option Activity

Stock option activity for the years ended December 31, 2021, 2020 and 2019 is as follows:

	Number of Shares Underlying Outstanding Options			Weighted- Ave rage Exercise Price per Share		Weighted- Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value
Outstanding—January 1, 2019		977,513		$	5.24		9.5	$	2,943
Options granted		913,090			8.25		7.5		206
Options exercised		(8,545	)		5.96		0.5		21
Options cancelled		(282,413	)		7.31				330
Outstanding—December 31, 2019		1,599,645		$	6.58		8.8	$	3,020
Options granted		37,663,242			0.45		9.4		363,941
Options exercised		(12,221,364	)		0.20		9.5		121,106
Options cancelled		(1,309,020	)		1.58				—
Outstanding—December 31, 2020		25,732,503		$	0.56		9.5	$	245,746
Options assumed through acquisition		823,114			5.05		8.3		125
Options granted		645,796			10.26		9.3		—
Options exercised		(2,155,348	)		0.22				10,742
Options cancelled		(916,969	)		0.30				4,492
Outstanding—December 31, 2021		24,129,096		$	1.01		8.6	$	100,992
Vested and expected to vest-December 31, 2021		24,129,096		$	1.01		8.6	$	100,992
Exercisable—December 31, 2021		9,332,369		$	0.74		8.5	$	41,587

Schedule of Stock Options Outstanding and Exercisable

The following table summarizes information about stock options outstanding and exercisable at December 31, 2021.

Options Outstanding						Options Exercisable
Options Outstanding		Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price		Options Exercisable		Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price
	5,548,717		8.4	$	0.18		3,492,915		8.4	$	0.18
	9,602,898		8.7	$	0.21		3,138,238		8.7	$	0.21
	7,524,114		8.8	$	1.42		2,194,532		8.8	$	1.42
	40,581		6.1	$	1.49		39,927		6.1	$	1.49
	766,989		7.8	$	5.24		466,757		7.8	$	5.24
	645,797		9.4	$	10.26		—		9.4	$	—
	24,129,096						9,332,369

Schedule of Stock Options Valuation Assumptions

The weighted-average assumptions in the Black-Scholes option-pricing models used to determine the fair value of stock options granted during the years ended December 31, 2021, 2020 and 2019 were as follows:

	Year Ended December 31,
	2021	2020	2019
Expected term (in years)	6.0	5.0—6.1	6
Risk-free interest rate	1.0%	0.3—1.5%	1.5%—2.4%
Expected volatility	63.2%	57.4%—63.3%	55.3%—58.0%
Expected dividend rate	0%	0%	0%

The weighted-average assumptions in the Black-Scholes option-pricing models used to determine the fair value of stock options assumed during the year ended December 31, 2021 were as follows:

	Year Ended December 31,
	2021
Expected term (in years)	3.1—5.6
Risk-free interest rate	0.8%—1.3%
Expected volatility	44.1%—48.6%
Expected dividend rate	0%

Schedule of Nonvested Restricted Stock Awards Activity

A summary of RSAs activity under the Plan is as follows:

	Number of Shares			Weighted Average Grant Date Fair Value (per share)
Unvested – January 1, 2020		34,865		$	0.58
Granted during the year		1,617,264			0.46
Canceled during the year		(105,921	)		0.35
Vested during the year		(1,505,454	)		0.52
Unvested – December 31, 2020		40,754		$	0.67
Granted during the year		—			—
Canceled during the year		—			—
Vested during the year		(23,288	)		0.67
Unvested – December 31, 2021		17,466		$	0.67

A summary of RSUs activity under the Plan is as follows:

	Number of Shares			Weighted Average Grant Date Fair Value (per share)
Unvested – January 1, 2021		—		$	—
Assumed through acquisition		4,490,980			6.55
Granted during the year		5,224,504			9.39
Canceled during the year		(552,072	)		8.89
Vested during the year		(509,786	)		10.30
Unvested – December 31, 2021		8,653,626		$	7.90