v3.0.0 - web interface, FSDP2 + context-parallel training

[bghira]

SimpleTuner v3

TL;DR

• User‑driven workflows, API‑centric design, and a calmer, smarter training experience.
• Big push on reliability, visibility, and integration: wizards, events, webhooks, CLI, and docs.
• Lays the groundwork for SimpleTuner v3 to truly be simple.

Highlights

• Unified, richer webhook/events system with stable interface that will not change much, moving forward.
• Dataset and training configuration wizards that hold your hand and help make fewer mistakes.
• FSDP2 and DeepSpeed fully integrated into the web interface, with more flexible and complete configuration capability.
• Packaging, CLI, Docker, and documentation updates that make things easier.

WebUI & UX

• Dataset Wizard and Training Configuration Wizard with guided steps.
• Event streaming: lifecycle states, event severity, progress bars, lightbox for convenient viewing of validation images.
• Clean interactivity: collapse/expand sections of the interface with persisted state to disk, ensuring the interfaces stays just as you left it the next time it's loaded.
• Support for custom themes to be expanded upon and fully-fleshed out in the next few releases

Data, Checkpoints & Validation

• Checkpoint overview card with validation previews; lightbox for images.
• Fixes for validation image counts, overwrites, and color profiles.
• Checkpoint deletion, filename/path normalization, and selection widgets.
• Hugging Face uploads: bulk/single with improved feedback and error surfacing.

Training Core

• Robust error detection and graceful recovery/cleanup on abort.
• Improved progress tracking (including text/image embed steps).
• Startup status surfaced in API with startup_progress.
• Safer defaults and guards (optimizers, schedulers, warmup, gradient accumulation).

Distributed & Hardware

• FSDP2 backend support with tests and docs; context parallel option.
• DeepSpeed builder UI and safer defaults; single‑GPU fixes for full-rank tuning big models like Flux on just 24G VRAM
• Hardware route for GPU info to allow displaying it in statistics dashboards or collecting for metrics over time.
• Guardrails for macOS/ROCm that disable or remove incompatible features from the interface to avoid confusion or accidental usage.

Webhooks & Events

• Unified event lifecycle; legacy ad-hoc messages are removed.
• Multi‑webhook backend with list config and SSL support.
• Mandatory readable_type for signal names; richer, raw payloads.
• Hardened against timeouts/connection closure; consistent logging.

API, CLI & Service

• Overhauled FastAPI service with API documentation generator.
• CLI entry point and service worker command added to just allow simpletuner server to launch everything.
• Dataset browse endpoint; improved dataloader factory and registry.
• APIState improvements for in‑context subprocess and progress tracking.

Performance & Stability

• Trainingsample Rust ops integrated for batched transforms (goodbye cv2).
• PyTorch upgraded to 2.8.0 or 2.9.0 depending on platform; TorchDynamo config granularity enhanced, with regional compile now possible to enable.

Security & Networking

• Webhook SSL support with auto‑disable verify if server started with SSL - or bring-your-own certificate and launch with a fully verified chain of authority.
• Env var & accelerate config handling refined; safer pipeline defaults.

Packaging, Install & Docs

• Shift to pip‑first workflows; Docker and notebooks updated accordingly.
• CLI launch recommendations unified across docs.
• FSDP2 and DeepSpeed docs; migration guide (2.1 → 2.2).
• API tutorial and current event list added; lots of errata and readability passes.

Removals & Breaking Changes

• Removed legacy webhook message format; use unified events stream.
• Removed Poetry configs
• No CWD fallback for config loading; be explicit about paths.

Quality & Tests

• Expanded unit/integration tests: webhooks (SSL/JSON/AST), events lifecycle, collapsible sections, hardware, backends, and CLI parsing.
• Better mocks for checkpoint tests; formatting/coverage cleanups.

Upgrade Notes

• Install/update via pip (see README for commands and extras).
• Review WEBHOOKS and Events docs for updated signal names and payloads:
  • documentation/api/WEBHOOKS.md
  • documentation/api/TUTORIAL.md

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This discussion was created from the release v3.0.0 - web interface, FSDP2 + context-parallel training.