Engineering Reference

This section is for developers and maintainers. It groups the maintained technical references that support implementation, debugging, and validation.

Runtime and architecture

architecture/architecture.md - firmware module map
architecture/boot_sequence.md - startup flow and phase ordering
architecture/configuration_system.md - compile-time vs runtime configuration
architecture/rtc_persistence.md - retained config and deep-sleep restore model
architecture/power_modes.md - power and sleep subsystem behavior
architecture/matrix_manager.md - matrix display layering and queue orchestration

integrations/bluetooth_overview.md - scanner-only BLE model
integrations/csi.md - Wi-Fi CSI runtime path
integrations/remote_access_cloudflare.md - planned customer remote access relay architecture
integrations/telegram_integration.md - Telegram runtime model, delivery path, and TLS policy
integrations/telegram_commands.md - Telegram command registry, polling rules, and extension notes

api-contract.md - firmware/frontend/SDK/API path contract and verifier
charts-ui.md - historical chart UX, trend normalization, and validation notes
frontend-quality.md - frontend quality gates, CI checks, and review rules
operations/security_hardening.md - security model and hardening notes
operations/testing.md - backend and frontend validation
operations/runtime-diagnostics.md - live heap, task, mutex, WebSocket, and restart diagnostics
operations/dram_optimizations.md - DRAM usage guidance
operations/hygienic_sleep.md - hygiene sleep and maintenance restart flow
../main_docs/BUILD_SPEED_OPTIMIZATION.md - measured PlatformIO build-speed optimization report