GrapheneOS development and updates have continued and will keep going. We have substantial funds available to hire more people to work on GrapheneOS. We'll need to hire multiple experienced developers to fill their big shoes. They'll hopefully be safe and when they return we'll have a bigger team.
If you're an experienced AOSP developer interested in working full time on GrapheneOS in a fully remote position, see https://grapheneos.org/hiring. We can pay people anywhere in the world via Wise (local bank transfers), BTC, ETH or XMR. We need people who can hit the ground running due to the current situation.
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