The fastest-growing open-source startups in Q4 2021

Key	Company	Country	City	Founded	Raised	Repo	Language	Stars	Forks	Stars AGR	Forks AGR	SG	FG
codenotary/immudb	CodeNotary	USA	Houston	2018	7.0	codenotary/immudb	Go	6,437	215	1,636	733	16.4	7.3
datreeio/datree	Datree	Israel	Tel Aviv	2017	11.0	datreeio/datree	Go	5,197	203	1,391	6,358	13.9	63.6
appsmithorg/appsmith	Appsmith	India	Bengaluru	2019	8.0	appsmithorg/appsmith	TypeScript	10,952	963	1,088	823	10.9	8.2
rowyio/rowy	Rowy	Australia	Sydney	2021		rowyio/rowy	TypeScript	2,524	165	882	659	8.8	6.6
radix-ui/primitives	Modulz	Ireland	Dublin	2019	5.4	radix-ui/primitives	TypeScript	2,670	82	774	323	7.7	3.2
fonoster/fonoster	Fonoster	USA	Cameron	2015		fonoster/fonoster	JavaScript	3,797	130	638	699	6.4	7.0
budibase/budibase	Budibase	UK	Belfast	2020	0.4	budibase/budibase	JavaScript	8,201	440	609	719	6.1	7.2
bytebase/bytebase	Bytebase	China	Shanghai	2021	3.0	bytebase/bytebase	Go	1,840	103	597	1,526	6.0	15.3
questdb/questdb	QuestDB	UK	London	2019	14.3	questdb/questdb	Java	7,651	404	549	511	5.5	5.1
builderio/mitosis	Builder	USA	San Francisco	2018	17.3	builderio/mitosis	TypeScript	3,810	128	548	432	5.5	4.3
rainbow-me/rainbow	Rainbow	USA	New York	2019		rainbow-me/rainbow	JavaScript	2,024	271	417	309	4.2	3.1
netless-io/flat	Netless	China	Hangzhou	2018	1.0	netless-io/flat	TypeScript	3,213	383	397	379	4.0	3.8
withfig/autocomplete	Fig	USA	San Francisco	2020	2.4	withfig/autocomplete	TypeScript	8,538	2,215	335	786	3.4	7.9
deepset-ai/haystack	deepset	Germany	Berlin	2018	1.6	deepset-ai/haystack	Python	3,507	599	306	110	3.1	1.1
openreplay/openreplay	OpenReplay	France	Paris	2018	1.5	openreplay/openreplay	JavaScript	2,971	108	301	373	3.0	3.7
mattermost/focalboard	Mattermost	USA	Palo Alto	2015	70.0	mattermost/focalboard	TypeScript	7,137	577	295	424	3.0	4.2
nomiclabs/hardhat	Nomic Labs	Argentina	Buenos Aires	2018		nomiclabs/hardhat	TypeScript	2,163	512	279	216	2.8	2.2
logseq/logseq	Logseq	China	Hangzhou	2020		logseq/logseq	Clojure	8,568	518	266	310	2.7	3.1
jitsucom/jitsu	Jitsu	USA	San Francisco	2019	2.0	jitsucom/jitsu	TypeScript	1,969	105	257	93	2.6	0.9
evidentlyai/evidently	Evidently	UK	London	2020	0.1	evidentlyai/evidently	Jupyter Notebook	1,944	162	242	218	2.4	2.2

CodeNotary (codenotary/immudb, 6.4K stars, 1636% AGR). Software supply chain audit based on the immutable database. Founded in 2018 in Houston and raised $7M from Elaia, Bluwat, Acequia Capital.
Datree (datreeio/datree, 5.2K stars, 1391% AGR). Automated policy checks for Kubernetes pipelines. Founded in 2017 in Tel Aviv and raised $11M from Blumberg Capital, TLV Partners, Y Combinator.
Appsmith (appsmithorg/appsmith, 11K stars, 1088% AGR). Framework for the building of admin panels, CRUD apps and workflows. Founded in 2019 in Bengaluru and raised $8M from Canaan Partners, Bessemer, Accel, OSS Capital.
Rowy (rowyio/rowy, 2.5K stars, 882% AGR). Extendable Airtable-like spreadsheet UI for databases. Founded in 2021 in Sydney and has no known external funding.
Modulz (radix-ui/primitives, 2.7K stars, 774% AGR). Code-based tool for designing and prototyping. Founded in 2019 in Dublin and raised $5.4M from LocalGlobe, Frontline, Tiny VC.
Fonoster (fonoster/fonoster, 3.8K stars, 638% AGR). Unified communication and telephony API (open-source alternative to Twilio). Founded in 2015 in Cameron, NC (USA) and has no known external funding.
Budibase (budibase/budibase, 8.2K stars, 609% AGR). Low-code platform for the building of internal tools. Founded in 2020 in Belfast and raised $391K from Techstart Ventures.
Bytebase (bytebase/bytebase, 1.8K stars, 597% AGR). Database schema change and version control for teams. Founded in 2021 in Shanghai and raised $3M from Matrix Partners China.
QuestDB (questdb/questdb, 7.7K stars, 549% AGR). Time-series database. Founded in 2019 in London and raised $14.3M from Episode 1, Y Combinator, 468 Capital, etc.
Builder (builderio/mitosis, 3.8K stars, 548% AGR). Low-code platform for building frontend (headless CMS). Founded in 2018 in San Francisco and raised $17.3M from Greylock, etc.
Rainbow (rainbow-me/rainbow, 2K stars, 417% AGR). Mobile Ethereum wallet for managing assets. Founded in 2019 and raised an unknown round from Digital Currency Group.
Netless (netless-io/flat, 3.2K stars, 397% AGR). Professional interactive whiteboard SDK. Founded in. 2018 in Hangzhou and raised $1M.
Fig (withfig/autocomplete, 8.5K stars, 335% AGR). Autocomplete for the terminal. Founded in 2020 in San Francisco and raised $2.4M from General Catalyst, SV Angel and YC.
deepset (deepset-ai/haystack, 3.5K stars, 306% AGR). NLP-based semantic search engine for enterprises. Founded in 2018 in Berlin and raised $1.6M from Tiny VC, Lunar Ventures, System.One, Acequia Capital, etc.
OpenReplay (openreplay/openreplay, 3K stars, 301% AGR). Session replay software (open-source alternative to Fullstory). Founded in 2018 in Paris and raised $1.5M from Kima Ventures and YC.
Mattermost (mattermost/focalboard, 7.1K stars, 295% AGR). Collaboration platform (open-source alternative to Slack). Founded in 2015 in Palo Alto and raised $70M from S28, Y Combinator, Redpoint, Battery Ventures, etc.
Nomic Labs (nomiclabs/hardhat, 2.2K stars, 279% AGR). A platform for development on Ethereum. Founded in 2018 in Buenos Aires and has no known external funding.
Logseq (logseq/logseq, 8.6K stars, 266% AGR). Knowledge base manager. Founded in 2020 in Hangzhou and has no known external funding.
Jitsu (jitsucom/jitsu, 2K stars, 257% AGR). Data ingestion engine (open-source alternative to Segment). Founded in 2019 in San Francisco and raised $2M from Costanoa Ventures, SignalFire, Y Combinator, etc.
Evidently (evidentlyai/evidently, 2K stars, 242% AGR). Toolset to analyze and monitor machine learning models in production. Founded in 2020 in London and raised $125K from Y Combinator.

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