Introducing the next era of Duende IdentityServer.

Read our CEO’s announcement

Stop Maintaining Workarounds. Modernize Your Identity Layer.

Centralize authentication and token security across fragmented legacy estates. Deliver secure SSO with velocity while eliminating technical debt and custom code using a modern, .NET-native identity infrastructure - all without application rewrites.

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Challenge

Modernization Without Rewrites Feels Impossible

Your business relies on critical .NET apps with hardcoded, outdated, or inconsistent authentication logic. Rewrites aren't feasible. Your team is trapped in manual patches, duplicated policies, and mounting security debt. Users face repeated logins, auditors flag outdated flows, and SaaS "modernization" solutions lack .NET-native integration, control, and phased rollout flexibility.

Impact of Doing Nothing

Identity Debt Compounds Silently

Without a central identity layer, teams remain buried in legacy authentication stacks. Policy changes take weeks, MFA and claims enforcement are inconsistent, every audit exposes new gaps, and technical debt accumulates with every customization. Friction rises as your team continues to be blocked by vendor rigidity, unable to quickly adopt modern standards or streamline security.

Duende IdentityServer Customers

Trusted by over 2,500 of the world's most standards-based and security-conscious organizations

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Solution

The .NET-Native Path to Modern Identity

Deliver SSO, central policy, and modern sessions across legacy apps - without the cost and risk of a full application rewrite. Duende introduces an identity foundation that modernizes authentication without touching business code.


Secure SSO for Legacy Apps

Protocol adapters deliver SSO even when legacy apps can't speak OIDC/OAuth.

Modern Session & Token Management

Adopt modern, secure standards for session and token issuance across your entire estate.


Central Policy & Extensibility

Uncompromised control over the UI, business logic, and policy plane. Define MFA rules, claims, and session lifetimes in one place, even for legacy users.


Modular Add-Ons - Extend When You're Ready

Add the capabilities you need as a flat-fee or usage-band add-on - avoid overpriced SaaS bundling and forced platform upgrades. Introducing: User Management, SAML, Financial-Grade Security & Conformance, Automatic Key Management, and Multi-Issuer.


Benefit

Modern Identity, No Rewrites Required

Eliminate compromise between control and commercial readiness. Centralize authentication to eliminate fragmentation, strengthen security, and modernize legacy apps - without the cost and risk of rewrites.

Replace ASP.NET Identity Debt

IdentityServer provides a modern user store with passkeys and MFA out of the box. No schema lock-in.

Bridge Legacy and Modern

SAML for legacy apps. OIDC for everything new. One identity hub.

.NET 10, Day One

Leaner packages, cleaner code paths, full access to the latest runtime capabilities.


Predictable at Scale

First-party modules replace the custom code that one developer maintains.


See Duende’s App Modernization in Action

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