Capitalization - Common stock Reserved (Details) - shares	Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Capitalization
Conversion of convertible preferred stock		27,799,267	22,520,015
Warrants to purchase convertible preferred stock	0	3,540,546	1,133,725
Warrants to purchase common stock		74,895	74,895
Number of shares available for grant		363,095	1,861,856
Stock options issued and outstanding under 2018 Stock Plan	14,960,960	15,712,434	3,209,063
Total shares of common stock reserved	61,560,172	107,435,982	28,799,554

Class of Warrant or Right, Number of Common Securities Called by Warrants or Rights

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- Definition

Class of Warrant or Right, Number of Convertible Preferred Securities Called by Warrants or Rights

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No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Number of shares issued for each share of convertible preferred stock that is converted.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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