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TempleOS: A Non-POSIX Operating System That Removed Protection on Purpose

Most operating systems are built around protection.

They separate user space from kernel space.
They isolate processes.
They assume programs are unsafe and must be controlled.

TempleOS was built by rejecting those assumptions entirely.

TempleOS is a real, bootable desktop operating system that intentionally runs everything in a single privilege level, without memory protection, without networking, and without modern security models.

This was not an accident.
It was the core design choice.

What This Operating System Is

TempleOS is a standalone 64-bit desktop operating system written almost entirely by one person.

It includes:
• its own kernel
• its own programming language (HolyC)
• a graphical desktop
• native applications
• its own build tools

There is no external userland.
There are no third-party libraries.
Everything runs inside one unified system.

TempleOS is not a fork, not a distribution, and not a compatibility layer.

Why TempleOS Exists

Most operating systems grow complex because they try to support:
• multiple users
• hostile programs
• networks
• long-running services

TempleOS exists because its creator wanted the opposite:
• a single-user system
• complete control
• immediate execution
• zero abstraction between code and hardware

The design goal was not safety or scalability.
It was clarity and immediacy.

In TempleOS, the system does exactly what the code says nothing more, nothing less.

Kernel

TempleOS uses a monolithic kernel with no separation between kernel mode and user mode.
Key characteristics:
• single address space
• no process isolation
• no virtual memory protection
• no preemptive multitasking

All code runs at the highest privilege level.

This makes the system:
• extremely simple
• extremely fast
• extremely fragile

The kernel does not defend the system.
It trusts the programmer completely.

POSIX Status

TempleOS is explicitly non-POSIX.

It does not implement:
• POSIX system calls
• Unix process model
• fork / exec
• signals
• permissions
• file descriptors

There is no attempt at Unix compatibility.

POSIX assumes:
• multi-user systems
• unsafe programs
• defensive kernels

TempleOS assumes:
• one trusted user
• one trusted program
• no hostile environment

Programming Model

TempleOS introduces HolyC, a language similar to C but tightly integrated with the OS.

Characteristics:
• direct hardware access
• no standard library separation
• code can modify the kernel at runtime
• immediate compilation and execution

There is no distinction between “application code” and “system code”.

Programming in TempleOS means programming the entire machine.

Processor Architecture

TempleOS targets:
• x86-64 only

It assumes:
• legacy BIOS boot
• a stable CPU environment
• no need for portability

Support for other architectures was never intended.

The OS is tightly bound to the hardware to keep the system small and predictable.

File System

TempleOS uses its own simple custom filesystem.

Filesystem characteristics:
• flat and minimal structure
• no permissions
• no journaling
• direct access

The filesystem exists to load and save code, not to manage users or security.

Data safety is the responsibility of the user, not the OS.

Hardware Requirements

TempleOS has very modest requirements.

Typical expectations:
• CPU: x86-64 processor
• RAM: very low by modern standards
• Storage: small disk footprint
• Graphics: fixed low-resolution mode

It runs best on:
• virtual machines
• older PCs

It is not designed for modern GPUs or peripherals.

Who Should Use TempleOS

TempleOS makes sense for people who:
• study operating system fundamentals
• want to understand life without protection layers
• explore extreme simplicity in system design
• are interested in OS history and philosophy

It is useful as:
• a conceptual reference
• an educational artifact
• a demonstration of design tradeoffs

Where TempleOS Does Not Make Sense

TempleOS is not suitable for:
• networking
• multi-user systems
• security-critical environments
• modern desktop workflows
• production use of any kind

It deliberately ignores almost everything modern OSs try to solve.

TempleOS matters not because it is practical, but because it is honest.

It shows what an operating system looks like when protection, compatibility, and scalability are removed entirely and reminds us that every safety feature in modern systems exists because something like this is no longer acceptable.

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