Is Geyser open source?

Yes — Geyser publishes its source code.

What category of service is Geyser?

Geyser is listed under Funding in the SatsAtlas services directory.

Services directory · Funding

Geyser

Crowdfunding on Bitcoin — launch a project page and raise sats over Lightning from anywhere.

Geyser is crowdfunding built on Bitcoin: creators launch a project page and raise sats over Lightning from supporters anywhere, with the open-source platform handling contributions and rewards. It is where a lot of grassroots Bitcoin and open-source projects run their fundraisers.

Compared with mainstream crowdfunding it keeps the whole flow Bitcoin-native and global from day one, with no card rails or geographic gatekeeping. It is aimed at builders, artists and causes in the space rather than commercial mega-campaigns, and its reach is strongest inside the Bitcoin community itself.

Official site @geyserfundopen source

Other funding services

OpenSats

A non-profit funding free and open-source Bitcoin development through donations and grants — where much of the ecosystem’s FOSS work is paid for.

Quick answers

What is Geyser?: Geyser is a Bitcoin funding service. Crowdfunding on Bitcoin — launch a project page and raise sats over Lightning from anywhere.
Is Geyser open source?: Yes — Geyser publishes its source code.
What category of service is Geyser?: Geyser is listed under Funding in the SatsAtlas services directory.

Explore the rest of the stack: wallets, where to buy and places that take Bitcoin. Facts describe each service's core product and can change — always verify on the official site.