Game Dev Best Practices

Scalable, performant, testable game code in Rust and Bevy.

How to Use This List

• Apply A-B at project start when scaffolding schedules and folders.
• Walk C-D before milestone demos and publisher builds.
• Revisit E after perf regressions or content scale-up.

A - ECS Design

• Keep components small and data-only. Behavior stays in systems, not methods on god structs.
• Use marker components for query filters. With<Enemy> beats string tags.
• Order systems explicitly when sharing mutable access. Scheduler conflicts serialize unexpectedly otherwise.
• Despawn hierarchies on scene exit. Leaked entities cause ghost collisions and memory creep.
• Prefer Commands for spawns/despawns. Structural changes batch safely in schedule.

B - Timing and Simulation

• Run physics in FixedUpdate only. Variable delta_secs in physics causes jitter and tunneling.
• Interpolate render transforms between fixed states. High FPS displays need smooth visuals.
• Cap fixed catch-up steps after hitches. Prevent spiral of death freezing gameplay.
• Sample input in Update, consume in fixed step via buffer if needed. Consistent control feel.
• Pause with virtual time, not busy loops. Menus should not advance simulation accidentally.

C - Assets and Content

• Consistent lowercase asset paths for Linux builds. Case mismatch passes on macOS, fails in CI.
• Wait for LoadState::Loaded before spawning gameplay. Placeholder pink textures signal missing gate.
• Compress audio and textures appropriately. OGG and GPU-compressed formats reduce load and VRAM.
• Version scene files with game releases. Old scenes with removed components need migration.
• Organize assets/ by domain (sprites, audio, scenes). Content creators navigate faster.

D - Performance and Shipping

• Profile Tracy/Puffin on min-spec hardware. Steam Deck and integrated GPU tell truth.
• Avoid per-frame allocations in hot systems. Reuse buffers in resources.
• Use diagnostics plugins in dev, not spam in release. println! in Update kills FPS.
• Release build with LTO for shipping. Debug builds misrepresent performance utterly.
• Test headless or minimal plugins in CI for logic. Not every test needs GPU window.

E - Team and Maintenance

• Pin Bevy to exact minor version. Read migration guide before bumping.
• Document control bindings and gamepad deadzones. QA reproduces bugs faster.
• Feature-flag debug overlays (collider draw, FPS). Ship clean player builds.
• Separate game crate from engine crate if scope grows. Reuse engine across titles.
• Record known Bevy/plugin version pairs in README. Onboarding avoids dependency hell.

FAQs

Related

• Bevy Engine - core patterns
• Game Loops & Timing - fixed step
• Performance for Games - profiling
• Game Dev Basics - orientation

Stack versions: This page was written for Rust 1.97.0 (edition 2024), Tokio 1.x, Axum 0.8, serde 1.0, sqlx 0.8, clap 4, and Polars 0.46+.