# theiphoneos1project/writeups architecture

> Architecture diagram of the GitHub repository theiphoneos1project/writeups, generated by GitDiagram from its file tree, README and a sample of source files (last updated 2026-08-01). It is an AI-made overview: check details against the source.

- Interactive diagram: https://gitdiagram.com/theiphoneos1project/writeups
- Repository: https://github.com/theiphoneos1project/writeups

## Overview

#### Purpose
This repository is documentation, not an application or buildable codebase. It collects engineering writeups from “The iPhone OS 1 Project,” focused on creating software for early Objective-C/iPhone OS 1 environments.

Primary entry point: `README.md`.

#### Documentation Modules
Two independent technical writeups form the repository’s core content:

- MicroInjector development experience: `MicroInjector/WRITEUP.md`
- Custom `ld64` linker work for Objective-C 1 platforms: `ld64/WRITEUP.md`

Each module also contains supporting images in its local `Images` directory:
- `MicroInjector/Images`
- `ld64/Images`

#### MicroInjector Stage
The MicroInjector material documents the design and development process for an injector-oriented component used in the project. Its architectural boundary is conceptual and documented rather than implemented in this repository.

Relevant paths:
- `MicroInjector/WRITEUP.md`
- `MicroInjector/Images`

#### Custom Linker Stage
The `ld64` material covers a custom linker required to target Objective-C 1-era platforms, explicitly including iPhone OS 1. This is the key platform/toolchain compatibility boundary represented by the repo.

Relevant paths:
- `ld64/WRITEUP.md`
- `ld64/Images`

#### Primary Flow
Reader navigation flows from the repository overview into one of the specialized writeups:

1. Start at `README.md`.
2. Select either the injector-development narrative or linker/toolchain narrative.
3. Consume inline/supporting visual material from the corresponding `Images` directory.

There is no executable runtime, service integration, deployment infrastructure, or source-level control flow visible in the supplied tree.

#### Licensing Boundary
The repository separates code and documentation licensing:

- MIT license for source-code material: `LICENSE`
- CC BY 4.0 for writeups: `LICENSE-WRITEUPS`

This distinction matters for downstream reuse: technical prose and images are governed separately from any referenced project code.

Main entry points: [`LICENSE-WRITEUPS`](https://github.com/theiphoneos1project/writeups/blob/main/LICENSE-WRITEUPS) (CC BY 4.0 License), [`ld64/WRITEUP.md`](https://github.com/theiphoneos1project/writeups/blob/main/ld64/WRITEUP.md) (Objective-C 1 Linker), [`README.md`](https://github.com/theiphoneos1project/writeups/blob/main/README.md) (Repository Overview), [`MicroInjector/WRITEUP.md`](https://github.com/theiphoneos1project/writeups/blob/main/MicroInjector/WRITEUP.md) (Injector Development)

## Diagram (Mermaid)

```mermaid
flowchart TD

subgraph group_microinjector["MicroInjector Writeup"]
  node_microinjector_writeup["Injector Development<br/>technical writeup<br/>[WRITEUP.md]"]
  node_microinjector_images["Supporting Visuals<br/>image collection"]
end

subgraph group_linker["Custom ld64 Writeup"]
  node_ld64_writeup["Objective-C 1 Linker<br/>technical writeup<br/>[WRITEUP.md]"]
  node_ld64_images["Supporting Visuals<br/>image collection"]
  node_platform_boundary{{"iPhone OS 1 Compatibility<br/>toolchain boundary"}}
end

subgraph group_licensing["Licensing"]
  node_code_license["MIT License<br/>code license"]
  node_writeup_license["CC BY 4.0 License<br/>documentation license"]
end

node_readme["Repository Overview<br/>documentation index<br/>[README.md]"]

node_readme -->|"navigates to"| node_microinjector_writeup
node_readme -->|"navigates to"| node_ld64_writeup
node_microinjector_writeup -->|"uses visuals"| node_microinjector_images
node_ld64_writeup -->|"uses visuals"| node_ld64_images
node_ld64_writeup -->|"addresses"| node_platform_boundary
node_code_license -.->|"governs code material"| node_readme
node_writeup_license -.->|"governs"| node_microinjector_writeup
node_writeup_license -.->|"governs"| node_microinjector_images
node_writeup_license -.->|"governs"| node_ld64_writeup
node_writeup_license -.->|"governs"| node_ld64_images

click node_readme "https://github.com/theiphoneos1project/writeups/blob/main/README.md"
click node_microinjector_writeup "https://github.com/theiphoneos1project/writeups/blob/main/MicroInjector/WRITEUP.md"
click node_microinjector_images "https://github.com/theiphoneos1project/writeups/tree/main/MicroInjector/Images"
click node_ld64_writeup "https://github.com/theiphoneos1project/writeups/blob/main/ld64/WRITEUP.md"
click node_ld64_images "https://github.com/theiphoneos1project/writeups/tree/main/ld64/Images"
click node_code_license "https://github.com/theiphoneos1project/writeups/blob/main/LICENSE"
click node_writeup_license "https://github.com/theiphoneos1project/writeups/blob/main/LICENSE-WRITEUPS"

classDef toneNeutral fill:#f8fafc,stroke:#334155,stroke-width:1.5px,color:#0f172a
classDef toneBlue fill:#dbeafe,stroke:#2563eb,stroke-width:1.5px,color:#172554
classDef toneAmber fill:#fef3c7,stroke:#d97706,stroke-width:1.5px,color:#78350f
classDef toneMint fill:#dcfce7,stroke:#16a34a,stroke-width:1.5px,color:#14532d
classDef toneRose fill:#ffe4e6,stroke:#e11d48,stroke-width:1.5px,color:#881337
classDef toneIndigo fill:#e0e7ff,stroke:#4f46e5,stroke-width:1.5px,color:#312e81
classDef toneTeal fill:#ccfbf1,stroke:#0f766e,stroke-width:1.5px,color:#134e4a
class node_microinjector_writeup,node_microinjector_images toneBlue
class node_ld64_writeup,node_ld64_images,node_platform_boundary toneAmber
class node_code_license,node_writeup_license toneMint
class node_readme toneNeutral
```

## Components

### MicroInjector Writeup

- [Injector Development](https://github.com/theiphoneos1project/writeups/blob/main/MicroInjector/WRITEUP.md): technical writeup · Documents the injector-oriented component's design and development. · `MicroInjector/WRITEUP.md`
- [Supporting Visuals](https://github.com/theiphoneos1project/writeups/tree/main/MicroInjector/Images): image collection · `MicroInjector/Images`

### Custom ld64 Writeup

- [Objective-C 1 Linker](https://github.com/theiphoneos1project/writeups/blob/main/ld64/WRITEUP.md): technical writeup · Documents custom ld64 work for iPhone OS 1-era targets. · `ld64/WRITEUP.md`
- [Supporting Visuals](https://github.com/theiphoneos1project/writeups/tree/main/ld64/Images): image collection · `ld64/Images`
- **iPhone OS 1 Compatibility**: toolchain boundary · The custom linker enables targeting Objective-C 1-era platforms.

### Licensing

- [MIT License](https://github.com/theiphoneos1project/writeups/blob/main/LICENSE): code license · Applies to source-code material. · `LICENSE`
- [CC BY 4.0 License](https://github.com/theiphoneos1project/writeups/blob/main/LICENSE-WRITEUPS): documentation license · Applies to writeups and images. · `LICENSE-WRITEUPS`

### Other components

- [Repository Overview](https://github.com/theiphoneos1project/writeups/blob/main/README.md): documentation index · Primary reader entry point. · `README.md`

## Connections

- Repository Overview → Injector Development: navigates to
- Repository Overview → Objective-C 1 Linker: navigates to
- Injector Development → Supporting Visuals: uses visuals
- Objective-C 1 Linker → Supporting Visuals: uses visuals
- Objective-C 1 Linker → iPhone OS 1 Compatibility: addresses
- MIT License → Repository Overview: governs code material
- CC BY 4.0 License → Injector Development: governs
- CC BY 4.0 License → Supporting Visuals: governs
- CC BY 4.0 License → Objective-C 1 Linker: governs
- CC BY 4.0 License → Supporting Visuals: governs