Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk> :toc: macro :icons: font :source-highlighter: rouge :experimental: :url-github: https://github.com/hyperpolymath/januskey :url-gitlab: https://gitlab.com/hyperpolymath/januskey :url-bitbucket: https://bitbucket.org/hyperpolymath/januskey :url-codeberg: https://codeberg.org/hyperpolymath/januskey

Reversible File Operations (formal proofs pending) Through Maximal Principle Reduction

Overview

JanusKey is a file operation utility suite that pursues complete reversibility through architectural design rather than logging or backups. Unlike traditional backup systems that restore from external state, JanusKey operations carry sufficient information for inversion — the goal is to make data loss architecturally impossible (formal proofs pending).

Key Features

• Reversible by design - Every operation carries inversion metadata (formal proofs pending)

• Instant Rollback - Undo changes in milliseconds

• Data loss impossible by construction - the architectural goal the pending proofs are to establish

• Complete Audit Trail - Every change tracked automatically

• Transaction Support - Group operations, commit/rollback together

• Content-Addressed Storage - SHA256 hashing with deduplication

Quick Start

# Build from source (requires Rust)
cd src/januskey
cargo build --release

# Initialize JanusKey in your project
jk init

# Delete files (reversible)
jk delete *.log

# Undo the delete
jk undo

# Transactions for batch operations
jk begin
jk delete temp*.txt
jk modify "s/DEBUG/INFO/g" config.yaml
jk preview   # Review changes
jk commit    # Or: jk rollback

Commands

Command	Description
jk init	Initialize JanusKey in current directory
jk delete <files>	Delete files (reversible)
jk modify <pattern> <files>	Modify files with sed-like syntax
jk move <src> <dst>	Move/rename files
jk copy <src> <dst>	Copy files
jk undo [--count N]	Undo last operation(s)
jk begin [name]	Start a transaction
jk commit	Commit current transaction
jk rollback	Rollback current transaction
jk preview	Preview pending changes
jk history	Show operation history
jk status	Show current status

Architecture

JanusKey implements Maximal Principle Reduction (MPR), a security methodology where vulnerability elimination occurs by construction rather than verification.

+----------------------------+
|       JanusKey CLI         |  <-- jk delete, jk modify, jk move
+----------------------------+
|      Operation Layer       |  <-- Generates inverse metadata
+----------------------------+
|    Transaction Manager     |  <-- Groups ops, commit/rollback
+----------------------------+
|      Metadata Store        |  <-- Append-only operation log
+----------------------------+
| Content-Addressed Storage  |  <-- SHA256, deduplication
+----------------------------+

Reversibility Guarantee

Every operation stores sufficient metadata for perfect inversion:

• Delete: Stores full content + metadata for restoration

• Modify: Stores original content hash for rollback

• Move: Stores original path for unmove

• Copy: Destination path for deletion

Installation

From Source (Rust)

# Clone the repository
git clone {url-github}
cd januskey/src/januskey

# Build release binary
cargo build --release

# Install to PATH
cargo install --path .

Mirrors

Platform	URL
GitHub (primary)	{url-github}
GitLab	{url-gitlab}
Bitbucket	{url-bitbucket}
Codeberg	{url-codeberg}

License

This project is licensed under the Mozilla Public License, v. 2.0. See the LICENSE file for details.

SPDX-License-Identifier: CC-BY-SA-4.0

Contributing

See CONTRIBUTING.

Research

JanusKey is based on research into reversible computing (formal proofs are a target, not yet complete) and Maximal Principle Reduction. See the white paper in docs/ for formal proofs and theoretical foundations.

Metadata

• Domain: software-development

• Framework: RSR (Rhodium Standard Repository)

• Language: Rust

• Dublin Core: .well-known/dc.xml

Architecture

See TOPOLOGY for a visual architecture map and completion dashboard.