Run anything. Nothing leaks. Never lags your machine.
ShellBox is a from-scratch sandbox system for executing untrusted binaries—APKs, game mods, scripts, cracked tools—inside a closed, isolated container with a hard memory ceiling. Powered by the 1X8H engine and a fully handwritten native desktop interface.
Status: IN DEVELOPMENT — README published early. Code, engine, and UI land here as they are verified.
| VirtualBox / full VMs | Containers | ShellBox | |
|---|---|---|---|
| RAM floor | ~512 MB–2 GB per VM | low | hard-capped, default 256 MB |
| Can freeze your host? | yes | yes (OOM) | no — watchdog kills on breach |
| Setup | heavy, drivers | root/daemon | single .exe |
| Isolation | strong | medium | strong (job objects / cgroups / seccomp) |
The sandbox never takes over the host. Enforced at four layers:
- Hard cap — Windows Job Object
PROCESS_MEMORYlimit / Linux cgroup v2memory.max. The OS itself refuses over-allocation; no userspace polling can miss it. - System reserve floor — engine reads total system RAM at startup; the host always keeps ≥ 1 GB or 15% (whichever is larger) outside sandbox reach.
- Watchdog — polls working set every 500 ms; breach or stall → immediate kill + telemetry event.
- Supervisor — if the watchdog dies, the parent process restarts it. There is no state where a sandbox runs unbounded.
Defaults: 256 MB RAM cap, 64 process limit, 1024 handle limit, 5% CPU rate, 30 s timeout, 100 MB workspace disk quota. All configurable per-run.
| Failure | Response |
|---|---|
| Memory breach (OOM attempt) | Job/cgroup limit refuses allocation; watchdog kills; event logged |
| Hang / infinite loop | Timeout kill; CPU rate limit keeps host responsive meanwhile |
| Fork bomb / process storm | Process count limit (64 default); excess spawns denied |
| Handle / FD exhaustion | Handle limit; sandbox terminated before host impact |
| Network escape attempts | Kill-switch: WFP (Windows) / nftables (Linux); all egress denied by default |
| Disk fill | Workspace quota; writes fail inside sandbox only |
| Sandbox binary crash | Exit captured, workspace reset to clean snapshot, host unaffected |
| Watchdog crash | Supervisor restarts it; no unbounded window |
| Privilege escalation attempt | Deny; sandbox runs at lowest integrity / nobody |
| Partial launch failure | Full rollback: handles, jobs, temp files released |
| Host under load already | Engine detects free RAM; refuses launch below reserve floor |
The isolation engine, named 1X8H, written entirely from scratch:
- No borrowed code. No QEMU, no VirtualBox SDK, no gVisor, no vendored libraries. Every line is original, MIT-licensed.
- Platform backends: Windows Job Objects + WFP, Linux cgroups v2 + seccomp + namespaces, macOS sandbox-exec profile (roadmap).
- Single purpose: keep untrusted code inside its box, at all times, on any machine.
A handwritten Win32 + DirectX 11 desktop application. Not Electron. Not Qt. Not ImGui. Not Python. Not a webview. Native window, native renderer, own widget code — from scratch.
git clone https://github.com/gc1dk/ShellBox.git
cd ShellBox
cmake -B build -S .
cmake --build build --config ReleaseRequirements: MSVC 2022 / Clang 16 / GCC 11, CMake 3.16+, C++17.
| Milestone | State |
|---|---|
| README + LICENSE published | done |
| 1X8H engine core (Windows job objects, memory caps) | in progress |
| Watchdog + supervisor loop | planned |
| Network kill-switch (WFP / nftables) | planned |
| Handwritten Win32 + DX11 interface | planned |
| Linux backend (cgroups v2 + seccomp) | planned |
| Telemetry / event log UI | planned |
| macOS backend | planned |
MIT — Copyright (c) 2026 Gc.idk (gc1dk). See LICENSE.
From scratch. Hard-capped. Host always wins.
— Gc.idk (aka Gc1dk)