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The quantum computing race has a new competitor. Amazon has announced it will partner with three firms to offer online access to prototype quantum processors.

Through a new service called Amazon Braket, customers will be able to test algorithms and calculations on quantum processors from D-Wave Systems, IonQ and Rigetti Computing.

Each of these three firms takes a different approach to making such processors, which rely on subatomic quantum effects. IonQ’s version uses trapped ions manipulated by lasers as quantum bits – or qubits, which are the equivalent to bits in classical computers. Rigetti uses superconducting qubits, as does D-Wave, but the latter’s device is a more limited system known as a quantum annealer, rather than a full-blown computer.

These various approaches to qubits all have drawbacks. “I think for Amazon they’re looking at this also as a time to see which one’s really going to work,” says Peter Chapman at IonQ. “Put us all on the marketplace and see who wins.”

Because quantum computers are finicky and expensive to maintain, Amazon has, for now, decided to partner with these firms rather than compete with the likes of Google and IBM by building its own device.

“I think it is safe to say that most organizations will never own a quantum computer, and will find the cloud-based, on-demand model a better fit. It may well be the case that production-scale quantum computers are the first cloud-only technology,” wrote Jeff Barr at Amazon Web Services in a .

“There’s no task any of these machines can solve these days that you can’t solve with your laptop or a cluster of computers. So for any practical purposes, this is premature,” says Itay Hen at the University of Southern California in Los Angeles. But he thinks that with Amazon acting as a front-end, more people will gain experience with quantum computers.

“Using them is not very easy, so they’re kind of providing an intermediate step and saying to the user, you don’t need to know anything about quantum computers to use them,” says Hen.

Amazon Braket isn’t the first cloud quantum computing service; Microsoft and IBM offer their own versions. The three firms involved with Braket have also made sessions on their processors available separately in the past.

Amazon could yet try to build a quantum computer. A spokesperson says the company will develop quantum hardware in the future.