Consolidated Statements of Convertible Preferred Shares and Shareholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Series C	Series D	Series D+	Ordinary Shares	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance (in shares) at Apr. 30, 2019	19,703,000
Beginning balance at Apr. 30, 2019	$ 38,132
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series D/D+ convertible preferred shares, net of issuance costs (in shares)		2,448,000	10,094,000
Issuance of Series D/D+ convertible preferred shares, net of issuance costs		$ 10,462	$ 50,023
Ending balance (in shares) at Apr. 30, 2020	32,245,000
Ending balance at Apr. 30, 2020	$ 98,617
Beginning balance (in shares) at Apr. 30, 2019					70,694,000
Beginning balance at Apr. 30, 2019	(12,817)				$ 4	$ 7,445	$ (170)	$ (20,096)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ordinary shares issued under employee share plan (in shares)					1,851,000
Ordinary shares issued under employee share plan	814					814
Share-based compensation	1,247					1,247
Total comprehensive loss	1,348						19	1,329
Ending balance (in shares) at Apr. 30, 2020					72,545,000
Ending balance at Apr. 30, 2020	$ (9,408)				$ 4	9,506	(151)	(18,767)
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series D/D+ convertible preferred shares, net of issuance costs (in shares)			9,934,000	8,630,000
Issuance of Series D/D+ convertible preferred shares, net of issuance costs			$ 49,465	$ 49,883
Ending balance (in shares) at Apr. 30, 2021	50,809,000
Ending balance at Apr. 30, 2021	$ 197,965
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ordinary shares issued under employee share plan (in shares)					2,613,000
Ordinary shares issued under employee share plan	1,448					1,448
Repurchase of ordinary shares (in shares)					(6,876,000)
Repurchase of ordinary shares	(22,908)				$ (1)	(932)		(21,975)
Share-based compensation	2,570					2,570
Total comprehensive loss	$ (27,133)						378	(27,511)
Ending balance (in shares) at Apr. 30, 2021	68,282,000				68,282,000
Ending balance at Apr. 30, 2021	$ (55,431)				$ 3	12,592	227	(68,253)
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series D/D+ convertible preferred shares, net of issuance costs (in shares)				1,251,000
Issuance of Series D/D+ convertible preferred shares, net of issuance costs				$ 7,245
Conversion of preferred shares into ordinary shares (in shares)	(52,060,000)
Conversion of preferred shares into ordinary shares	$ (205,210)
Ending balance (in shares) at Apr. 30, 2022	0
Ending balance at Apr. 30, 2022	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ordinary shares issued under employee share plan (in shares)					3,029,000
Ordinary shares issued under employee share plan	2,731					2,731
Share-based compensation	9,188					9,188
Total comprehensive loss	(22,380)						(204)	(22,176)
Conversion of preferred shares to ordinary shares (in shares)					52,060,000
Conversion of preferred shares into ordinary shares	205,210				$ 3	205,207
Issuance of common stock in connection with initial public offering, net of offering costs, underwriting discounts and commissions (in shares)					21,384,000
Issuance of common stock in connection with initial public offering, net of offering costs, underwriting discounts and commissions	194,205				$ 1	194,204
Warrant contra revenue	$ 640					640
Ending balance (in shares) at Apr. 30, 2022	144,755,000				144,755,000
Ending balance at Apr. 30, 2022	$ 334,163				$ 7	$ 424,562	$ 23	$ (90,429)