NTDev has released a major overhaul of the Tiny11 builder, supercharging it with a single PowerShell script that can surgically remove Copilot, the new Outlook client, and Microsoft Teams from Windows 11 installation images, while slashing ISO sizes through DISM’s recovery compression. The September 2025 refresh marks a decisive step for power users and administrators who want Windows 11 without the inbox app clutter or the newest AI‑first integrations.

Windows 11’s Growing Bloat and the Tiny11 Solution

Windows 11 has steadily morphed from a lean operating system into a curated, service‑centric experience laden with preinstalled apps, cloud hooks, and AI features like Copilot. For many, these additions are bloat—unwanted software that consumes storage, clutters the interface, and potentially raises privacy concerns. Enter Tiny11, a community project that rebuilds official Windows ISOs with the fat trimmed off. The latest builder refines that process into a transparent, repeatable PowerShell pipeline, putting granular control directly in the hands of enthusiasts and IT pros.

What’s New in the September 2025 Builder

PowerShell‑First Pipeline and Broader Compatibility

Gone are the brittle batch scripts of old. The builder now runs as a single PowerShell script—tiny11maker.ps1—that handles everything from image selection to final ISO creation. The rewrite brings reliable cross‑locale and cross‑architecture support, targeting any Windows 11 release (WIM or ESD), on x64 or arm64, in multiple languages. No third‑party image tools are needed beyond Microsoft’s own oscdimg.exe from the Windows ADK.

One‑Click Removal of Copilot, Outlook, and Teams

The headline feature is explicit removal routines for Copilot, the web‑backed “new Outlook,” and the consumer‑grade Teams client. These join a long list of purgeable inbox apps: Clipchamp, OneDrive, Mail & Calendar, GetHelp, Feedback Hub, and many Xbox apps (with Xbox Identity Provider left intact for those who want to reinstall). Registry tweaks baked into the script attempt to lock the door on silent reinstallation, though the project acknowledges it’s a game of whack‑a‑mole as Microsoft evolves its servicing pipeline.

DISM Recovery Compression: Smaller ISOs, Heavier Builds

The builder now exports the modified image using DISM /Compress:recovery—a solid‑compression mode that applies LZMS/LZX algorithms, the same ones used for Microsoft’s own ESD distribution files. The result is a dramatically smaller ISO, but the trade‑offs are steep: exports take significantly longer and consume far more RAM. On machines with limited memory, DISM may fail with out‑of‑memory errors, so NTDev recommends a beefy build environment.

Tiny11 Core: The Ultra‑Lean, Non‑Serviceable Variant

Alongside the standard builder, a tiny11Coremaker.ps1 script now ships. This experimental profile goes nuclear: it removes the Windows Component Store (WinSxS), disables or deletes Windows Update, and strips out defensive components like Microsoft Defender. The image that results is tiny and fast—perfect for sandboxed VMs or lab testbeds—but it cannot be serviced or updated. The maintainer’s warnings are unambiguous: “Core is not suitable for production machines.”

Under the Hood: How the Builder Works

Tiny11’s pipeline is a masterclass in offline image servicing, leaning exclusively on Microsoft tools:

  • Start with an official Windows 11 ISO containing a WIM or ESD file.
  • Mount the desired image index using DISM.
  • The script removes packages, optional components, scheduled tasks, language packs, and registry entries according to a configurable removal profile.
  • The pruned image is exported with recovery compression for a smaller footprint.
  • Finally, oscdimg.exe reassembles the payload into a bootable ISO, optionally injecting an autounattend.xml to bypass Microsoft Account enforcement during OOBE.

The entire sequence is transparent—a boon for administrators who need to audit or tweak the process for their specific environments.

The Good: Why Power Users Are Excited

Focused AI and Mail Client Removal

For users who see Copilot, Outlook, and Teams as privacy sinkholes or resource hogs, having a repeatable, scriptable removal method eliminates tedious post‑install cleanup. The registry blocks reduce the chance these components creep back after a feature update or Store refresh.

Leaner Footprints for Constrained Hardware

Smaller ISOs and a lighter runtime footprint make Windows 11 viable on storage‑starved devices and VMs where every gigabyte counts. The recovery compression move alone yields distribution size wins that matter when pushing images across a lab network or hosting them on slow links.

Tooling Transparency and Repeatability

The open PowerShell script and reliance on DISM/ADK mean no opaque binary packers, no mystery alterations. Image builders can version‑control the script, integrate it into CI/CD pipelines, and validate each step. Multi‑SKU support means one workflow covers anything from Windows 11 Home to Enterprise, in any language.

Reduced Background Churn

By culling auto‑updating inbox apps and background tasks, administrators get a quieter, more predictable OS. That’s gold for kiosks, digital signage, test rigs, and ephemeral virtual desktops that don’t need a constant stream of Store updates.

The Caution Tape: Risks and Real‑World Caveats

Serviceability and Update Fragility

Even the standard (non‑Core) profile removes components that future cumulative updates may expect to find. The result can be failed patches, forced reboots, or the resurrected apps NTDev tried to bury. The script includes mitigations, but it’s not a permanent fix. And the Core variant intentionally breaks servicing; expect no help from Windows Update on those installations.

Security Exposure (Especially Core)

Stripping WinSxS, Windows Update, and Defender leaves a machine naked. An internet‑connected Core machine is a security incident waiting to happen. The project and community stress that Core is for air‑gapped testbeds only—not your daily driver.

Compatibility and Driver Quirks

Removing platform pieces can trigger unexpected breakage. Hardware drivers may depend on seemingly unrelated components; Settings pages can throw errors; certain apps may refuse to launch. Testers have reported boot loops and device‑specific failures when combining Tiny11 with Windows Insider preview builds. These are empirical, environment‑dependent risks that demand thorough validation.

Build Resource Demands

Recovery compression is a RAM hog. Expect DISM to crash on machines with less than 16 GB—NTDev and community notes call out 32 GB or more as a safer baseline. Build times also balloon; plan your image creation sessions accordingly, perhaps overnight.

Support and Licensing Landmines

Modified images are unsupported by Microsoft. Enterprises with support contracts should treat Tiny11 as an unsanctioned configuration that could void assistance or violate compliance policies. Home users typically can activate with a valid key, but the legal line grows fuzzier in organizational settings.

Should You Use It? Practical Deployment Guidance

Good Use Cases

  • Test VMs and ephemeral lab images where disk footprint and boot speed trump serviceability.
  • Kiosks, digital signage, or single‑purpose appliances that are locked down and don’t need monthly patches.
  • Hobbyist exploration on spare hardware, with the understanding that a rebuild may be necessary after major updates.
  • Offline rescue environments or storage‑constrained systems.

Cases to Avoid

  • Production endpoints that require consistent Windows Update servicing and Microsoft support.
  • Internet‑facing machines that rely on built‑in security features (especially when considering the Core profile).
  • Environments bound by strict vendor support contracts that forbid modified OS images.

A Safe Workflow

  1. Back up all data and have a recovery plan before deploying any custom image.
  2. Build on a well‑resourced machine with ample RAM (32 GB recommended) and fast SSD storage.
  3. Start with the standard Tiny11 profile; avoid Core for any scenario that touches a network.
  4. Test the image exhaustively against your hardware, applications, and update scenarios (monthly rollups, feature updates).
  5. If you must use Core for constrained VMs, keep them offline or tightly network‑segmented, and rebuild rather than patch.
  6. Version‑control the builder scripts, and audit the registry and scheduled‑task modifications before mass deployment.

Verifying the Claims

All key technical assertions in this release are publicly documented and verifiable:

  • The GitHub repository and NTDev’s announcement explicitly list Copilot, the new Outlook client, and Teams as new removal targets.
  • The switch to DISM recovery compression is confirmed in the README and release notes; the LZMS/LZX solid compression behavior aligns with official Microsoft documentation.
  • The Tiny11 Core variant’s non‑serviceable nature and removal of WinSxS and update hooks are prominently warned about in the repo and project commentary.

Still, remember that builder behavior varies with input images, selected options, and the exact removal flags used. Always validate against your own test runs before trusting these images in any critical path.

The Bottom Line

NTDev’s Tiny11 builder update is a powerful, transparent tool for a defined audience: lab rats, embedded‑system builders, and privacy‑minded tinkerers. It combines a modern PowerShell pipeline with surgical removal of Copilot, Outlook, and Teams, plus aggressive compression for lean ISOs. But the sharp edges are real: heavier build requirements, fragile servicing, and the security‑blunted Core variant demand a careful hand. The project is well‑documented and honest about its trade‑offs—a refreshing contrast to black‑box “optimizers.” For the right use cases, it’s a repeatable, reliable way to reclaim Windows 11. For everyone else, a supported, vanilla install remains the wiser path.