Intro

Auth0's a workable option for many companies, including startups.

Startup founders should bear in mind, however, that it's a single product line within a very large, publicly-traded company that makes the bulk of its money from large enterprises.

There are better options for startups. In particular, Tesseral is a modern, open source Auth0 alternative for B2B SaaS founders.

Why startups pick Auth0 at first

"Nobody gets fired for buying IBM"

Auth0 has been around a while. Founded in 2013, Auth0 became part of publicly-traded Okta in 2022. That's a long track record.

Lots of careful enterprises pick Auth0. For example, the United Kingdom's National Health Service (NHS) opted to use Auth0 in a rewrite of a legacy PHP application.

If you prioritize social proof, it's hard to find something better established than Auth0.

Other factors

Auth0 also does a few other things really well. They have immense brand awareness. They cover almost every possible framework nicely in their documentation.

We often see people try Auth0 because, well, it's the safe choice -- and they go to production because it works well enough as a prototype.

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Why startups sometimes look for alternatives

Pricing

Sometimes people ask me to estimate what they'd be paying for Auth0. I can rarely give them a straight answer -- in large part because the pricing is complicated!

It's not uncommon for people to feel a bit upset about pricing changes, too. I don't think it's Auth0's fault, really. I just think some people aren't their ideal customers.

Looking for a better fit for SaaS

Auth0 wants to serve all customer identity use cases. If you make some kind of software, they want to handle your auth.

I don't think that's quite the right way to do things. Developer tools are often at their best when they're opinionated, when they steer you into a pit of success, when they focus narrowly on being excellent at one thing.

And auth for SaaS isn't that similar to auth for consumer software like social media or ecommerce, as I've written previously.

Because it serves a broad range of use cases, Auth0 sometimes has to be complicated. Again, it's not their fault. It's just a product that needs to do a lot of different stuff for a lot of different kinds of customers.

Looking for something startup-friendly

Startup founders like to know that their vendors care deeply about their business. That experience is relatively uncommon when working with big companies in general, but especially when big companies have many enterprise customers.

Startup founders don't generally want to hear "you didn't file your paperwork."

Looking for something open source

Auth0 is proprietary, closed source software. You can't look under the hood at the source code, make modifications, or run it just anywhere. You need a commercial relationship with Okta (Auth0 parent company) on their terms.

Lots of startups look for open source alternatives. There are a few major reasons, including:

1. Long-term stability: auth is pretty foundational infrastructure. A lot of your code will depend on the behavior of your auth system. Some founders don't like the idea that a commercial auth service can just make unilateral changes (e.g., deprecating certain APIs).
2. Self-hosting: if you start getting your own enterprise customers -- especially in regulated industries -- you'll start getting requests for private cloud or on-prem deployments. It's way easier to do this when you're working with open source software. You can run it however you want.
3. Customization: again, auth is pretty foundational infrastructure. You want it to work for your use case. If you want open source software to work differently, well, you can just change it!
4. Transparency: for something security-critical like auth, lots of founders take some comfort in knowing exactly how things work -- in knowing that the maintainers are adherent to sound security practices.

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Tesseral: open source alternative to Auth0 for startups

What is Tesseral?

Tesseral is open source auth for B2B SaaS. With just a few lines of code, you get everything you need: from a simple login page to enterprise single sign-on, managed API keys, and more. It'll work nicely out of the box, and you'll be pleasantly surprised as you scale; when enterprise customers start asking for things (RBAC, SCIM, audit logs), you'll find that Tesseral just takes care of them for you.

Founders for founders

Our customers are mostly startups, and we're still independent and founder-led. In fact, you can book time directly with a founder here. Founders handle all support requests.

Open source

You can find our source code on GitHub and do whatever you want with it! You can open a GitHub issue if you have a feature request or even fork our code if you want -- run it anywhere.