meta: CODEOWNERS, PR template, issue forms, SECURITY.md, CONTRIBUTING.md

.github/CODEOWNERS

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+# All files — Benjamin is the default reviewer for every PR
+* @benjamineckstein

.github/ISSUE_TEMPLATE/bug_report.yml

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+name: Bug Report
+description: Something broke or behaves unexpectedly
+labels: ["bug"]
+body:
+  - type: textarea
+    id: what_happened
+    attributes:
+      label: What happened?
+      description: Describe the bug clearly.
+    validations:
+      required: true
+
+  - type: textarea
+    id: steps
+    attributes:
+      label: Steps to reproduce
+      description: How can we reproduce the issue?
+      placeholder: |
+        1. Open the game
+        2. Place a residential zone
+        3. ...
+
+  - type: textarea
+    id: expected
+    attributes:
+      label: Expected behaviour
+      description: What should have happened instead?
+
+  - type: dropdown
+    id: where
+    attributes:
+      label: Where did it happen?
+      options:
+        - Godot game window
+        - Headless runner / CLI
+        - Simulation logic (Core)
+        - Other
+
+  - type: input
+    id: version
+    attributes:
+      label: Loopolis version / commit
+      placeholder: "e.g. main@abc1234"

.github/ISSUE_TEMPLATE/feature_request.yml

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+name: Feature Request
+description: Suggest a new mechanic or improvement
+labels: ["enhancement"]
+body:
+  - type: textarea
+    id: feature
+    attributes:
+      label: What would you like to see?
+      description: Describe the feature or improvement you have in mind.
+    validations:
+      required: true
+
+  - type: textarea
+    id: why
+    attributes:
+      label: Why would this improve the game?
+      description: What problem does it solve or what fun does it add?
+
+  - type: textarea
+    id: implementation
+    attributes:
+      label: Any implementation ideas?
+      description: Optional — sketches, references, prior art welcome.

.github/PULL_REQUEST_TEMPLATE.md

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+## What does this PR do?
+
+<!-- One-line summary -->
+
+## Checklist
+
+- [ ] `dotnet test` passes locally
+- [ ] New systems have NUnit tests
+- [ ] No Godot imports in `Loopolis.Core`
+- [ ] Godot scripts compile (`cd godot && dotnet build`)
+- [ ] Balance checked (ran a scenario via headless runner if touching simulation math)

CONTRIBUTING.md

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+# Contributing to Loopolis
+
+Thanks for your interest in contributing! Loopolis is a solo indie project open to community improvements. Keep PRs small and focused — that makes review fast and merges easy.
+
+Website: https://www.codewithagents.de
+
+---
+
+## Getting Started
+
+**Prerequisites**
+
+- [.NET 10 SDK](https://dotnet.microsoft.com/download)
+- [Godot 4.4.1 .NET edition](https://godotengine.org/download) — install to `/Applications/Godot_mono.app` on macOS or adjust paths accordingly
+
+**Clone and build**
+
+```bash
+git clone https://github.com/codewithagents/loopolis-city-builder.git
+cd loopolis-city-builder
+dotnet build src/
+```
+
+---
+
+## Run Tests
+
+All simulation logic lives in `src/Loopolis.Core/` and is covered by NUnit tests. Run them with:
+
+```bash
+dotnet test
+```
+
+Tests complete in under 5 seconds — no Godot startup required.
+
+---
+
+## Run the Game
+
+### Standalone mode (Godot runs its own simulation)
+
+```bash
+DOTNET_ROOT=/opt/homebrew/opt/dotnet/libexec \
+  /Applications/Godot_mono.app/Contents/MacOS/Godot \
+  --path /path/to/loopolis/godot/ \
+  --editor
+# Open scenes/World.tscn and press F5
+```
+
+### Server + viewer mode (headless simulation + Godot viewer)
+
+```bash
+# Terminal 1 — start simulation server
+export DOTNET_ROOT="/opt/homebrew/opt/dotnet/libexec"
+dotnet run --project src/Loopolis.Runner -- server default --speed 2
+
+# Terminal 2 — launch Godot viewer
+DOTNET_ROOT=/opt/homebrew/opt/dotnet/libexec \
+  /Applications/Godot_mono.app/Contents/MacOS/Godot \
+  --path /path/to/loopolis/godot/ \
+  --editor
+# Open scenes/World.tscn and press F5
+```
+
+### Headless balance checks
+
+```bash
+dotnet run --project src/Loopolis.Runner -- 500 default
+dotnet run --project src/Loopolis.Runner -- 1000 powered_start
+```
+
+Output is JSON — useful for verifying simulation balance without opening Godot.
+
+---
+
+## How to Contribute
+
+1. **Fork** the repository
+2. **Create a branch** — `git checkout -b feat/my-feature`
+3. **Implement** Core changes first (if any), then Godot presentation
+4. **Test** — `dotnet test` must be green; Godot must compile (`cd godot && dotnet build`)
+5. **Open a PR** — fill in the PR template
+
+---
+
+## Rules
+
+- **No Godot imports in `Loopolis.Core/`** — ever. Core is pure C# with zero engine dependencies.
+- **Every new system needs NUnit tests** — test files mirror source paths (e.g. `Simulation/MySystem.cs` → `tests/.../Simulation/MySystemTests.cs`).
+- **No business logic in `Program.cs` or `World.cs`** — wiring only.
+- **Keep PRs small and focused** — one feature or fix per PR makes review much easier.
+- **Balance check** — if you touch simulation math, run a headless scenario and include the output (or a summary) in the PR description.
+
+---
+
+## Questions?
+
+Open a [GitHub Discussion](https://github.com/codewithagents/loopolis-city-builder/discussions) or reach out via the website: https://www.codewithagents.de

SECURITY.md

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+# Security Policy
+
+## Reporting a Vulnerability
+
+Please do **not** file a public GitHub issue for security vulnerabilities.
+
+Instead, send an email to **umingo@gmail.com** with the subject line:
+
+> Loopolis Security
+
+We will respond within **72 hours** and coordinate a fix before any public disclosure.
+
+## Non-Security Bugs
+
+For ordinary bugs and unexpected behaviour, please use [GitHub Issues](https://github.com/codewithagents/loopolis-city-builder/issues).