A stripped-down, community-built version of Windows 11 has pushed the limits of what the OS can be when every nonessential component is removed: tiny installation media, dramatic runtime compression, and the deliberate sacrifice of serviceability and security to reach an astonishingly small storage footprint. The engineering behind these “diet” builds—most notably the Tiny11 family and its more radical relatives—shows that the modern Windows desktop is largely a collection of optional components chosen by Microsoft, not immutable requirements. At the same time, the technical tricks used to shave gigabytes off an OS come with sharp trade-offs: no updates, crippled security, and an image that cannot be patched or extended without rebuilding it from scratch.
Windows has ballooned over the last decade as new features, stores, services, and telemetry systems were folded into the base image. Projects such as Tiny11 and its experimental derivatives aim to reverse that trend by scripting the removal of UI apps, services, and even core subsystems, then applying advanced compression to squeeze the remaining binaries down.
Two engineering levers make this possible:
However, the moment a system must be patched, exposed to the internet, or used for anything beyond strictly controlled test scenarios, the costs of minimalism become prohibitive. Security, maintenance, and legal risks outweigh the convenience of a few gigabytes of saved space for any production use. The projects are best seen as engineering showcases and narrow-purpose tools rather than drop-in replacements for supported Windows installations.
The practical course for most users is clear: reserve extreme de-bloating for experimentation and VMs, use supported lightweight configurations for daily work, and insist that any production image preserve updateability and endpoint protection. The broader takeaway is more hopeful: Windows can be smaller when it must be, and that knowledge creates leverage—both for administrators who need lightweight environments and for anyone who wants Microsoft to offer a more modular, configurable baseline in future releases.
Source: theregister.com Nano11 cuts Windows 11 down to size and then some
Windows has ballooned over the last decade as new features, stores, services, and telemetry systems were folded into the base image. Projects such as Tiny11 and its experimental derivatives aim to reverse that trend by scripting the removal of UI apps, services, and even core subsystems, then applying advanced compression to squeeze the remaining binaries down.Two engineering levers make this possible:
- Pruning — programmatic removal (or disabling) of UWP apps, optional features, services, stores, and bundled consumers of telemetry and background CPU cycles.
- Runtime/System compression — using Windows’ CompactOS and advanced WIM compression modes (LZX, LZMS, and related algorithms) so system binaries on disk are held compressed and decompressed on demand.
What Nano11 and “core” builds actually do
The engineering recipe
Most of the extreme Windows slimming projects follow the same pattern:- Start from an official Windows 11 image that carries a valid SKU.
- Use deployment tooling (DISM, WIMGAPI, or other Microsoft-supplied utilities) to mount the image offline.
- Remove packaged app families and registered feature packages (Clipchamp, Xbox, News, Weather, Mail, Calendar, Your Phone, Teams, Copilot hooks, and more).
- Remove or disable services and scheduled tasks that are not strictly required to boot a basic desktop.
- Strip the WinSxS component store aggressively to eliminate duplicate or optional binary sets.
- Apply high-ratio WIM/Recovery compression (LZX or LZMS) to the offline image or enable CompactOS on installation, compressing system binaries on disk.
- Create a new ISO using Microsoft’s oscdimg or ADK tooling.
Features removed and consequences
Common removals include:- All or most modern UWP/WinUI bundled apps (News, Weather, Media Player, Office Hub, Solitaire, etc.).
- Microsoft Edge (or conversion to a minimal client).
- Background services like telemetry connectors and optional platform agents.
- Windows Update or many pieces of the servicing stack.
- Windows Defender/Defender components and associated security agents.
- Parts of the WinSxS store, which normally allow safe servicing and component replacement.
- Language packs, optional components, and recovery image pieces.
- No Windows Updates or severely degraded updateability if the servicing stack is removed.
- No built-in anti-malware if Defender is removed—leaving the system vulnerable unless a substitute is installed and maintained manually.
- Unserviceable image: you cannot easily add drivers, languages, or features to a machine installed from a deeply pruned image; doing so typically requires rebuilding the image and re-deploying.
- Activation and licensing remain an unresolved practical step—these builds are not a license bypass, and a valid Windows license is still required for lawful use.
The compression trick: CompactOS, LZX and LZMS
Compression is the other half of the story. Windows provides a supported command-line tool and API surface for compressing system binaries.- CompactOS (compact.exe /CompactOs) can compress OS binaries in place. It supports different executable compression algorithms and specifically exposes LZX as the most compact option for system executables.
- For offline WIM images and recovery containers, higher-ratio algorithms such as LZMS and LZX (in Recovery mode) are commonly used to create much smaller WIM/ISO payloads.
- Compression reduces disk footprint dramatically—often many gigabytes.
- Decompression on demand consumes CPU, and very aggressive WIM compression or CompactOS LZX can require a significant amount of RAM during recompression or image creation.
- The time to build or update an LZX/LZMS-compressed image is measurably higher than with default XPRESS compression, and some builders warn that the process "uses A LOT of RAM" and can take a long time.
How small can Windows 11 get — and what those numbers mean
Extreme reductions have been demonstrated in the wild. Two distinct trends show up repeatedly:- Tiny11 Core-style builds have been published that produce ISO files around 2 GB and installed footprints around 3–4 GB by combining aggressive pruning with LZX/LZMS compression.
- Nano11 and similar “superlite” builds aim to go further with deeper removals of services (including Windows Update and Defender) and WinSxS pruning, producing installed images reported at single-digit gigabytes and in some reports pushing below 3 GB on disk.
- Reported sizes depend on exactly which SKU (Enterprise, Pro, LTSC, IoT) is used as the base image, which language packs are kept, and whether compression is applied offline or via CompactOS after installation.
- Some size claims come from individual builders or early tests; independent verification is not always available. Where a specific number could not be reconciled across independent sources, it should be considered a claim rather than an established universal fact.
Why this matters: legitimate use cases
Despite the risks, the engineering achievement is useful in clearly defined contexts:- Virtual machines (VMs) and rapid testbeds — a tiny, static desktop is ideal for ephemeral VMs where updateability and long-term security are not required, such as automated testing, driver test benches, and CI environments.
- Embedded systems and appliances — devices that run a fixed workload and receive software via an update-controlled image can benefit from a leaner runtime.
- Legacy hardware resurrection — machines that otherwise cannot run stock Windows 11 due to storage constraints or low I/O capability can sometimes be given a usable desktop for light tasks.
- Research and education — studying how Windows is constructed and what is optional helps developers and admins understand system dependencies and attack surfaces.
The security and maintenance trade-offs — stark and unavoidable
Removing Defender, Windows Update, and the servicing stack is not a minor limitation. It converts the OS into a static artifact that will not receive security fixes or new component updates. That has three major consequences:- Rapidly increasing attack surface: Windows receives frequent patching for privilege escalation, remote execution, and privilege misuse. An unpatched system becomes an obvious target.
- Incompatibility with new drivers and peripherals: New hardware may require updated drivers; a non-serviceable image cannot accept new driver packages without rebuilding the whole image.
- Regulatory and compliance problems: Organizations that must meet security baselines cannot run unpatched, unsupported builds on corporate networks.
Legal and licensing considerations
Stripping a Windows image does not remove the need for a valid license. These community builds:- Are unofficial and unsupported by Microsoft.
- Do not grant any license rights beyond those contained in a legitimate Windows license purchased or assigned to the hardware.
- May technically run afoul of EULAs depending on the nature of modifications and redistribution, especially when redistribution of modified Microsoft binaries occurs.
Practical guidance: how to experiment safely
If testing an extreme Windows build is of interest, follow conservative steps:- Use a dedicated virtual machine rather than physical hardware. Snapshots and rollback points make experiments safe and reversible.
- Keep the VM offline initially. Validate behavior, drivers, and baseline functionality in an isolated network before introducing connectivity.
- Create a separate test network for any required internet access, and employ an external endpoint protection gateway if internet access is needed.
- Take a full snapshot before installing any production-facing applications; maintain a living build process so you can rebuild and reimage rather than patch in-place.
- Keep originals of official Windows ISOs and recovery media ready—don’t rely on a pruned image as your recovery plan.
- Verify licensing and compliance before placing any lightweight build into a production or semi-public environment.
The broader significance: what these projects say about Windows design
The existence and popularity of Tiny11, Tiny11 Core, Nano11, and similar projects are a clear message from users: many buyers want a modular, minimal Windows that can be tailored to constrained hardware and specific workloads without fighting a massive monolithic image.- Technically, Microsoft’s platform supports aggressive trimming. The component model and CompactOS infrastructure make it possible to keep only what’s strictly necessary.
- Politically and economically, though, the bundled features, telemetry, and store integration are part of a broader product and business strategy. Those choices favor a richer out-of-the-box experience for a general audience at the expense of minimalism.
- Projects like Nano11 demonstrate that the default Windows footprint is a choice, not an immovable technical constraint.
Strengths and notable engineering achievements
- Impressive storage reduction: Shrinking a multi-gigabyte OS install down to a few gigabytes (and in some experimental builds to a couple of gigabytes) is a real technical feat that combines component analysis with modern compression.
- Tooling leverage: The builders rely exclusively on official deployment utilities (DISM, compact.exe, oscdimg) in many cases, which means the process is reproducible and does not require obscure binary patching.
- Modularity awareness: The projects make visible which parts of Windows are optional and how the system behaves when those parts are removed—valuable insight for admins, OEMs, and Microsoft itself.
- Useful for constrained environments: For VMs, embedded appliances, and some development scenarios, a static, tiny image is an efficient solution.
Risks, unknowns, and limitations
- Unserviceable images: If you remove the servicing stack or prune the component store aggressively, you cannot feasibly add languages, features, or drivers later—rebuilding the image is the only practical path.
- Security posture: Removing Defender and updates creates a fragile security model. These builds should never be used for everyday production tasks that require network access or hold sensitive data.
- Compatibility costs: Some software assumes the presence of certain OS components. Removing them can cause subtle failures that only appear under specific conditions.
- Upgrade fragility: Microsoft updates have the power to reintroduce dependencies or change behavior in ways that break custom builds. There is no guarantee a future update won’t render the minimized image unusable.
- Verification gap: Size claims and capabilities vary between builders and versions; some headline numbers are single-instance measurements that may not generalize. Treat dramatic size claims as conditional until verified in a reproducible build.
Final assessment
The work behind Nano11 and the Tiny11 lineage is an impressive technical achievement and a practical demonstration that Windows 11’s large baseline is largely an assembly choice, not a fixed requirement. For tightly controlled use—VM testbeds, appliances with locked-down update processes, or one-off experiments—these builds provide a lean, fast way to run a Windows desktop environment.However, the moment a system must be patched, exposed to the internet, or used for anything beyond strictly controlled test scenarios, the costs of minimalism become prohibitive. Security, maintenance, and legal risks outweigh the convenience of a few gigabytes of saved space for any production use. The projects are best seen as engineering showcases and narrow-purpose tools rather than drop-in replacements for supported Windows installations.
The practical course for most users is clear: reserve extreme de-bloating for experimentation and VMs, use supported lightweight configurations for daily work, and insist that any production image preserve updateability and endpoint protection. The broader takeaway is more hopeful: Windows can be smaller when it must be, and that knowledge creates leverage—both for administrators who need lightweight environments and for anyone who wants Microsoft to offer a more modular, configurable baseline in future releases.
Source: theregister.com Nano11 cuts Windows 11 down to size and then some