From c3736be4f7a65d7fc6b7a4cd3ea1f4290eb11887 Mon Sep 17 00:00:00 2001
From: Alexander Zinn <alexzinnde@gmail.com>
Date: Fri, 24 Oct 2025 00:57:18 -0400
Subject: [PATCH] Initial Commit

---
 .gitignore                        |  3 ++
 .prettierrc                       | 12 +++++
 DependencyInjection/.gitignore    | 34 ++++++++++++++
 DependencyInjection/README.md     | 74 +++++++++++++++++++++++++++++++
 DependencyInjection/package.json  | 17 +++++++
 DependencyInjection/tsconfig.json | 29 ++++++++++++
 6 files changed, 169 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 .prettierrc
 create mode 100644 DependencyInjection/.gitignore
 create mode 100644 DependencyInjection/README.md
 create mode 100644 DependencyInjection/package.json
 create mode 100644 DependencyInjection/tsconfig.json

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..0ca0b3d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+.DS_Store
+
+node_modules/
diff --git a/.prettierrc b/.prettierrc
new file mode 100644
index 0000000..caa814d
--- /dev/null
+++ b/.prettierrc
@@ -0,0 +1,12 @@
+{
+  "arrowParens": "avoid",
+  "bracketSameLine": true,
+  "bracketSpacing": false,
+  "printWidth": 160,
+  "semi": true,
+  "singleAttributePerLine": false,
+  "singleQuote": true,
+  "tabWidth": 2,
+  "trailingComma": "none",
+  "useTabs": false
+}
diff --git a/DependencyInjection/.gitignore b/DependencyInjection/.gitignore
new file mode 100644
index 0000000..a14702c
--- /dev/null
+++ b/DependencyInjection/.gitignore
@@ -0,0 +1,34 @@
+# dependencies (bun install)
+node_modules
+
+# output
+out
+dist
+*.tgz
+
+# code coverage
+coverage
+*.lcov
+
+# logs
+logs
+_.log
+report.[0-9]_.[0-9]_.[0-9]_.[0-9]_.json
+
+# dotenv environment variable files
+.env
+.env.development.local
+.env.test.local
+.env.production.local
+.env.local
+
+# caches
+.eslintcache
+.cache
+*.tsbuildinfo
+
+# IntelliJ based IDEs
+.idea
+
+# Finder (MacOS) folder config
+.DS_Store
diff --git a/DependencyInjection/README.md b/DependencyInjection/README.md
new file mode 100644
index 0000000..ea2f0e3
--- /dev/null
+++ b/DependencyInjection/README.md
@@ -0,0 +1,74 @@
+# Simple Dependency Injection Container
+
+A learning project to understand how Dependency Injection works by building one from scratch.
+
+Inspired by the Phenix RTS platform's DI system.
+
+## Learning Goals
+
+1. Understand how DI containers resolve dependencies
+2. Learn about different lifecycle patterns (singleton, transient, factory)
+3. Understand circular dependency detection
+4. Learn about provider patterns
+5. Understand type registration and resolution
+
+## Steps
+
+We'll build this incrementally:
+
+1. **Step 1**: Basic container with manual registration
+2. **Step 2**: Constructor injection
+3. **Step 3**: Singleton vs Transient lifecycles
+4. **Step 4**: Circular dependency detection
+5. **Step 5**: Provider pattern
+6. **Step 6**: Named registrations
+7. **Step 7**: Configuration-driven DI (like Phenix's di.json)
+
+## Running the Examples
+
+```bash
+# Step 1 - Basic
+node step1-basic.js
+
+# Step 2 - Constructor Injection
+node step2-constructor-injection.js
+
+# Step 3 - Lifecycles
+node step3-lifecycles.js
+
+# Step 4 - Circular Dependencies
+node step4-circular-deps.js
+
+# Step 5 - Providers
+node step5-providers.js
+
+# Step 6 - Named Registrations
+node step6-named.js
+
+# Step 7 - Configuration
+node step7-config.js
+```
+
+## Key Concepts
+
+### Dependency Injection
+
+Instead of creating dependencies inside a class, they are "injected" from outside.
+
+### Inversion of Control (IoC)
+
+The container controls object creation and lifecycle, not your code.
+
+### Service Locator vs DI
+
+DI is better because dependencies are explicit in constructor signatures.
+
+## Architecture
+
+```
+Container
+├── Registry (stores type registrations)
+├── Resolver (resolves dependencies)
+├── Lifecycle Manager (handles singleton/transient)
+└── Provider System (custom creation logic)
+```
diff --git a/DependencyInjection/package.json b/DependencyInjection/package.json
new file mode 100644
index 0000000..80452e0
--- /dev/null
+++ b/DependencyInjection/package.json
@@ -0,0 +1,17 @@
+{
+  "name": "dependencyinjection",
+  "module": "index.ts",
+  "type": "module",
+  "private": true,
+  "scripts": {
+    "step:1": "bun run src/Step1",
+    "step:2": "bun run src/Step2"
+  },
+  "devDependencies": {
+    "@types/bun": "latest",
+    "prettier": "3.6.2"
+  },
+  "peerDependencies": {
+    "typescript": "5.9,3"
+  }
+}
diff --git a/DependencyInjection/tsconfig.json b/DependencyInjection/tsconfig.json
new file mode 100644
index 0000000..bfa0fea
--- /dev/null
+++ b/DependencyInjection/tsconfig.json
@@ -0,0 +1,29 @@
+{
+  "compilerOptions": {
+    // Environment setup & latest features
+    "lib": ["ESNext"],
+    "target": "ESNext",
+    "module": "Preserve",
+    "moduleDetection": "force",
+    "jsx": "react-jsx",
+    "allowJs": true,
+
+    // Bundler mode
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "verbatimModuleSyntax": true,
+    "noEmit": true,
+
+    // Best practices
+    "strict": true,
+    "skipLibCheck": true,
+    "noFallthroughCasesInSwitch": true,
+    "noUncheckedIndexedAccess": true,
+    "noImplicitOverride": true,
+
+    // Some stricter flags (disabled by default)
+    "noUnusedLocals": false,
+    "noUnusedParameters": false,
+    "noPropertyAccessFromIndexSignature": false
+  }
+}