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ModPageSpeed 2.0 and mod_pagespeed 1.1 — Now available

IISpeed alternative

IISpeed is deprecated because We-Amp consolidated two IIS code paths into one (mod_pagespeed 1.1). Existing customers get a free license transfer. IISpeed was We-Amp's native IIS port of mod_pagespeed, first released in 2012 — image optimization, CSS/JS minification, and critical CSS injection on the IIS pipeline for Windows-hosted sites.

Try mod_pagespeed 1.1 — 14 days free Transfer my IISpeed license

IISpeed is now deprecated. Existing customers get a free license transfer to either mod_pagespeed 1.1 (native IIS port) or to the WeAmp.PageSpeed NuGet middleware for ASP.NET Core. Support continues, but bug fixes and security patches have stopped.

This page explains both forward paths.

What IISpeed was

IISpeed wrapped the mod_pagespeed optimization libraries in an IIS module (IISpeedModule.dll) that registered against the IIS request pipeline. Configuration sat in web.config under <system.webServer>. Filters, variants, and the admin console all worked the same way as the Apache and nginx ports.

Customers ran it on Windows Server 2008 R2 through 2019. The IIS module ABI stayed compatible across those releases.

Why it's deprecated

  • The .NET 4 and IIS 7-era toolchain is increasingly painful to build and test against modern Windows.
  • AVIF, Core Web Vitals signals, and modern variant fan-out never landed.
  • Customer demand consolidated on either drop-in IIS upgrades (where 1.1 fits) or on ASP.NET Core middleware (where the NuGet package fits).
  • One IIS code path is better than two. The IIS port now lives inside mod_pagespeed 1.1, shared with Apache, nginx, and Envoy.

See ADR-003 for the full deprecation reasoning.

Path 1 — mod_pagespeed 1.1 for IIS

If you have an IIS deployment and want a drop-in replacement, mod_pagespeed 1.1 has a native IIS port with the same module surface IISpeed offered. Same web.config syntax, same filters, same admin console — plus security patches, modern toolchain, AVIF, and Cyclone Cache. 

<!-- web.config -->
<system.webServer>
  <modules>
    <add name="ModPagespeedModule" type="ModPagespeed.IIS.Module, ModPagespeed.IIS" />
  </modules>
  <pagespeed enabled="true">
    <fileCachePath>C:\inetpub\modpagespeed\cache</fileCachePath>
  </pagespeed>
</system.webServer>

The MSI installer at packages.modpagespeed.com/iis registers the module, creates the cache directory, and warm-starts the worker.

mod_pagespeed 1.1 docs · Download the MSI

Path 2 — WeAmp.PageSpeed NuGet middleware for ASP.NET Core

If your stack is ASP.NET Core, IIS is no longer the natural integration point — middleware is. The WeAmp.PageSpeed NuGet package adds optimization inside the ASP.NET Core pipeline: 

// Program.cs
using WeAmp.PageSpeed;

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddPageSpeed();

var app = builder.Build();
app.UsePageSpeed();
app.Run();
dotnet add package WeAmp.PageSpeed

The middleware reuses the mod_pagespeed 1.1 core via P/Invoke against a native library shipped inside the NuGet package. No IIS module registration, no web.config editing, no gacutil. Works on Windows, Linux, and container deployments of ASP.NET Core.

How the middleware integrates · NuGet package

Which path fits

Use caseChoose
Classic ASP.NET / WebForms / MVC 5 on IIS mod_pagespeed 1.1 for IIS
Existing IISpeed install you want to keep running with security patches mod_pagespeed 1.1 for IIS
ASP.NET Core 6+ on Kestrel or IIS WeAmp.PageSpeed NuGet middleware
Container deployment of an ASP.NET Core app WeAmp.PageSpeed NuGet middleware
Mixed environment (some sites on classic IIS, some on .NET Core) Run both — they share the same core and admin console

License transfer

If you hold an IISpeed license, the transfer to mod_pagespeed 1.1 or to WeAmp.PageSpeed is free and processed manually. Email license@we-amp.com with your IISpeed license key. The replacement key arrives within one business day.

Trial keys auto-issued on iispeed.com still work for the transition window documented at iispeed.com.

Frequently asked questions

Is IISpeed still supported?

Support continues for existing customers, but IISpeed is deprecated and bug fixes and security patches have stopped. New IIS deployments should use mod_pagespeed 1.1 for IIS, and ASP.NET Core deployments should use the WeAmp.PageSpeed NuGet middleware.

How do I transfer my IISpeed license?

Email license@we-amp.com with your IISpeed license key. The replacement key for mod_pagespeed 1.1 or WeAmp.PageSpeed arrives within one business day. The transfer is free.

What replaces IISpeed for IIS deployments?

mod_pagespeed 1.1 ships a native IIS module with the same web.config surface IISpeed offered — same filters, same admin console, plus security patches, modern toolchain, and AVIF.

Does WeAmp.PageSpeed work with classic ASP.NET?

WeAmp.PageSpeed is ASP.NET Core middleware. For classic ASP.NET / WebForms / MVC 5 on IIS, mod_pagespeed 1.1 for IIS is the right path — it's an IIS module, no application code changes required.

Can I run both mod_pagespeed 1.1 and the NuGet middleware?

Yes. Mixed environments are supported. Both reuse the same optimization core and share an admin console.

Try one

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