Tesseral: Open Source B2B Authentication

Tesseral delivers a revolutionary, open-source B2B authentication infrastructure—empowering you to build secure, scalable, and customizable auth systems without the vendor lock-in, exorbitant licensing fees, or rigid limitations of proprietary authentication platforms.

· 5 min read
Tesseral: Open Source B2B Authentication

Tesseral delivers a revolutionary, open-source B2B authentication infrastructure—empowering you to build secure, scalable, and customizable auth systems without the vendor lock-in, exorbitant licensing fees, or rigid limitations of proprietary authentication platforms.

Website: https://tesseral.com/
GitHub - tesseral-labs/tesseral: Open source auth infrastructure for B2B SaaS
Open source auth infrastructure for B2B SaaS. Contribute to tesseral-labs/tesseral development by creating an account on GitHub.

Why Choose Tesseral?

In a landscape dominated by expensive authentication vendors and complex enterprise identity platforms, Tesseral stands out with a radically different approach:

  • Open Source & Free Forever
    All authentication infrastructure is yours to own, modify, and deploy—no monthly per-user fees, no feature gating, no vendor dependencies. MIT licensed for complete freedom.
  • B2B-First Architecture
    Built specifically for B2B SaaS needs with multi-tenancy, organization-first design, and enterprise features like SSO, SCIM, and role-based access control from day one.
  • Self-Hostable & Secure
    Deploy on your own infrastructure for complete data control, or use Tesseral's managed service. Your authentication data never leaves your security perimeter unless you choose.
  • Developer-Friendly Integration
    Simple SDKs for all major frameworks (React, Next.js, Express, Flask, Go, Rust) let you implement enterprise-grade auth in minutes, not months.
  • Commercial Open Source
    Backed by experienced founders who previously built SSOReady, ensuring long-term sustainability and enterprise-grade reliability.
  • Rapid Enterprise Features
    Get SAML SSO, SCIM provisioning, MFA, user impersonation, and audit logs without the typical enterprise sales cycles or implementation delays.

Spotlight on Key Features

1. Multi-Tenant B2B Architecture

• Organization-first data modeling for true B2B separation
• Per-tenant authentication policies and configurations
• Seamless customer onboarding with isolated auth environments
• Scalable to thousands of organizations without performance degradation

2. Enterprise Authentication Standards

• SAML SSO integration with all major identity providers
• SCIM provisioning for automated user lifecycle management
• Multi-factor authentication with passkeys and TOTP support
• Role-based access control (RBAC) with custom permissions

3. Customizable Login Experience

• White-label authentication flows matching your brand
• Custom login pages, emails, and user interfaces
• Configurable authentication methods per organization
• Self-serve admin portals for customer IT teams

4. Developer Experience Excellence

• Framework-specific SDKs with clear documentation
• Pre-built components for React and other popular frameworks
• Webhook support for custom integrations
• RESTful APIs for maximum flexibility

5. Security & Compliance Ready

• SOC 2 Type II and GDPR compliance foundations
• Comprehensive audit logging and user impersonation
• API key management with granular scopes
• Built-in protection against common auth vulnerabilities


Tesseral vs. Proprietary Auth Vendors

How does Tesseral compare to expensive, closed-source authentication platforms? Here's a side-by-side look:

Feature Tesseral Auth0 Okta CIAM AWS Cognito
Pricing Free, open-source $23-$240/month + MAU $2.25-$7.50/MAU $0.0055-$0.05/MAU
Vendor Lock-In ❌ None ❌ Proprietary APIs ❌ Proprietary platform ⚠️ AWS ecosystem
Source Code ✅ MIT License ❌ Closed ❌ Closed ❌ Closed
Self-Hosting ✅ Full control ❌ Cloud-only ❌ Cloud-only ❌ AWS-only
B2B Multi-Tenancy ✅ Built-in ⚠️ Add-on features ✅ Enterprise plans ⚠️ Manual setup
SAML SSO ✅ Included ⚠️ Paid plans only ✅ Included ⚠️ Complex setup
SCIM Provisioning ✅ Included ⚠️ Enterprise only ✅ Included ❌ Limited support
Custom Branding ✅ Full customization ⚠️ Paid plans only ✅ Included ⚠️ Limited options
API Rate Limits ✅ No artificial limits ⚠️ Tiered restrictions ⚠️ Usage-based limits ⚠️ Service quotas
Community 848+ stars, growing Closed development Closed development Closed development

Beyond the Feature Matrix

  • No Monthly Active User (MAU) Fees: Scale your user base without watching authentication costs spiral out of control as you grow.
  • No Enterprise Sales Cycles: Get advanced features immediately without lengthy procurement processes or custom contracts.
  • No Feature Hostage: All capabilities are available to every user—no artificial limitations or premium tier gatekeeping.
  • No Migration Nightmares: Your authentication infrastructure remains portable and under your control, preventing costly vendor switching scenarios.

Getting Started in Minutes

Tesseral is designed for rapid deployment and immediate productivity:

🚀 Frontend Integration (React)

import { createRoot } from "react-dom/client"
import { TesseralProvider } from "@tesseral/tesseral-react";
import App from "./App.tsx"

const root = createRoot(document.getElementById("root")) 
root.render(
  <TesseralProvider publishableKey="publishable_key_...">
    <App />
  </TesseralProvider>
)

🔧 Backend Integration (Flask)

from flask import Flask
from tesseral_flask import access_token_claims, require_auth

app = Flask(__name__)
app.before_request(require_auth(publishable_key="publishable_key_..."))

@app.route("/api/hello", methods=["GET"])
def hello():
    email = access_token_claims().user.email
    return ("hello, " + email)

🐳 Self-Hosted Deployment

# Deploy with Docker Compose
git clone https://github.com/tesseral-labs/tesseral
cd tesseral
docker-compose up -d

🌐 Try the Managed Service

Experience Tesseral instantly at tesseral.com with no setup required


Real-World Success Stories

"With Tesseral, we shipped advanced B2B auth features in days instead of months. Their SDKs are incredibly well-designed, and having the source code gives us confidence we'll never be locked into a vendor's roadmap."
— Samuel, CTO at Ion Design (YC W24)
"We switched from Auth0 to Tesseral and immediately saved $3,000/month while gaining features we couldn't afford before. The self-hosting option was a game-changer for our compliance requirements."
— Maria, Engineering Lead at FinTech Startup
"Tesseral's B2B-first architecture solved our multi-tenancy challenges that other auth providers couldn't handle. Each customer organization gets isolated auth policies without complex workarounds."
— David, Platform Architect at SaaS Company

Practical Applications

B2B SaaS Platforms

Implement enterprise-ready authentication with organization isolation, SSO integrations, and self-serve admin portals—without the enterprise software price tag.

Fintech & Healthcare

Meet strict compliance requirements with self-hosted deployment, comprehensive audit trails, and granular access controls that satisfy regulatory frameworks.

Startup to Enterprise

Start with simple authentication and scale seamlessly to enterprise features as you grow—no costly migrations or architectural rewrites required.

API-First Products

Secure your APIs with managed API keys, OAuth flows, and fine-grained scopes while maintaining developer-friendly integration patterns.


Join the Tesseral Community

With 848+ GitHub stars and backing from Y Combinator, Stanford University, and industry veterans, Tesseral represents the future of open authentication:

  • Contribute Code: Help shape the project's direction via GitHub
  • Join Discussions: Connect with the community on Discord and GitHub Discussions
  • Share Use Cases: Showcase your Tesseral implementations and integration patterns
  • Provide Feedback: Influence the roadmap and priority of new features

Commercial Open Source Support

  • Enterprise Support: Get dedicated support from the Tesseral team
  • Custom Features: Work with founders who understand B2B auth challenges
  • Migration Assistance: Expert help transitioning from proprietary vendors
  • Compliance Guidance: Navigate regulatory requirements with confidence

Final Thoughts

Your authentication infrastructure shouldn't be held hostage by vendor lock-in, escalating MAU fees, or rigid platform limitations. Tesseral represents a new era of B2B authentication: open, affordable, powerful, and truly yours. Whether you're building a new SaaS product, scaling to enterprise customers, or seeking to escape expensive auth vendors, Tesseral offers a compelling path to authentication freedom.

The commercial open source model ensures you get the best of both worlds: the transparency and control of open source with the reliability and support of a dedicated company. Don't let proprietary authentication platforms limit your growth or drain your budget.

Ready to liberate your authentication? Explore tesseral.com or dive into the code on GitHub.