Session 201 — Progress Report

What This Session Accomplished

Session 200 connected all the pieces. Session 201 made them production-ready. Think of it like this: S200 built a working car; S201 added seatbelts, a dashboard, a fuel gauge, and door locks.

Timeline of Changes

Step 1: Backend Stability (S201.5)

What happened: Before any new features, we stabilized the existing backend services. Several packages were missing (error monitoring, task queues, AI sandboxes, cloud storage), and key services needed resilience improvements.

What was done:

• Installed 11 missing packages that were causing build failures
• Added a circuit breaker and retry logic for LLM (AI) API calls
• Improved the conversation compression and genome services
• Enhanced GitLab and Cloudflare integrations

What this means: All three backend servers (API, AI-API, Vitto-API) now compile and run without errors. AI calls that temporarily fail will automatically retry instead of crashing.

Step 2: Server Restart Recovery (S201.6 — Feature 5.1)

Before: If the Vitto server restarted while code was being generated (which happens during deployments), all progress updates were lost. Users would see a blank screen and have to start over.

After: Every progress event is now saved to the database as it happens. If the server restarts, the system replays all saved events when the user reconnects. No progress is lost.

Why this matters: Our hosting platform (Railway) redeploys containers periodically. Without this, any generation running during a redeploy would lose all its progress tracking. Now it's seamless — users don't even notice the restart.

Technical approach: "Dual-write" — events stream live for instant updates AND save to the database for recovery. The database copy auto-deletes after 24 hours (events are temporary).

Step 3: Generation Summary in Chat (S201.6 — Feature 5.4)

Before: After 15 minutes of code generation, the user saw individual progress messages but no cohesive summary. They had to piece together what happened from dozens of small updates.

After: When generation completes, Vitto posts a formatted summary message in the chat:

## Generation Complete

Generated **5 modules** with **143 files**

### Modules
- Player Management
- Team Management
- Match Management
- Statistics Dashboard
- Club Admin Portal

**Quality Score:** 85/100

**Review:** [View Merge Request](https://gitlab.com/...)

Why this matters: Users get immediate, clear feedback on what was built. The clickable "View Merge Request" link takes them directly to the code review page in GitLab.

Step 4: Pipeline Cost Visibility (S201.6 — Feature 5.5)

Before: Users had no idea how much a generation cost. The pipeline visualizer showed phase names and status but no financial information or detailed error messages.

After: The pipeline visualizer now shows:

• Cost per phase — A small badge on each pipeline node showing its estimated cost (e.g., "$0.04")
• Total cost — Displayed in the footer (e.g., "Estimated cost: $0.12")
• Model tier — Which AI model was used (Opus, Sonnet, or Haiku) and its pricing
• Error details — When a phase fails, an expandable panel shows the exact error message

Why this matters: Cost transparency builds trust. Users can see exactly where their money goes and identify expensive phases. Error details help both users and support teams diagnose issues faster.

Step 5: One-Click Rollback (S201.6 — Feature 5.7)

Before: If a generation produced broken code or unwanted results, there was no way to undo it from the Studio interface. Users would need to manually revert commits in GitLab.

After: A "Rollback Last Generation" button appears in the git status bar after any generation. One click reverts all changes from the last generation. The button shows loading state during the revert and displays a success/error message when done.

Why this matters: Mistakes are inevitable. Users need a safety net. This removes the fear of trying something new — if it doesn't work, just click rollback.

Step 6: Security — Space Isolation (S201.6 — Feature 5.6)

Before: The Studio and Module Generation endpoints had no authentication or authorization. Technically, anyone who knew the URL format could access any user's generated code.

After: All Studio endpoints now require:

1. Authentication — A valid login session (JWT token)
2. Authorization — Proof that the logged-in user owns the space they're trying to access

Results are cached for 5 minutes to keep things fast.

Why this matters: This is a fundamental security requirement for any multi-user system. Without it, User A could potentially see or modify User B's generated platform code. Now that's impossible.

What's Working Now (Complete Pipeline)

1. User describes platform    → "Build a soccer club management system"
2. Vitto generates code       → 5 modules, 150+ files (parallel, cost-tracked)
3. Code saved to GitLab       → Draft merge request for review
4. Summary in chat            → Module list, file count, quality score, MR link
5. Studio shows files         → Loaded from GitLab (cloud-based)
6. User edits in Studio       → Changes auto-commit to GitLab
7. Pipeline shows progress    → Per-phase cost, error details, model tier
8. User deploys               → One-click to Cloudflare Pages
9. Something wrong?           → One-click rollback
10. Server restarts?          → Automatic reconnection, no data loss
11. Multi-user?               → Each user sees only their own spaces

What's Deferred (Future Sessions)

Key Numbers

Session Commits

Architecture After S201

                    ┌─────────────────────────┐
                    │     Vitto Chat UI        │
                    │  (generation summary,    │
                    │   SSE reconnection)      │
                    └──────────┬───────────────┘
                               │
                    ┌──────────▼───────────────┐
                    │   Vitto Studio UI         │
                    │  (pipeline cost display,  │
                    │   rollback button,        │
                    │   file editing)           │
                    └──────────┬───────────────┘
                               │
              ┌────────────────┼────────────────┐
              │                │                 │
    ┌─────────▼──────┐  ┌─────▼──────┐  ┌──────▼──────┐
    │ JwtAuthGuard   │  │ SpaceOwner │  │  @Public()  │
    │ (all endpoints)│  │ Guard      │  │  (SSE only) │
    └─────────┬──────┘  └─────┬──────┘  └──────┬──────┘
              │               │                 │
    ┌─────────▼───────────────▼─────────────────▼──────┐
    │              Vitto API (port 3003)                │
    │                                                   │
    │  ┌─────────────┐  ┌──────────┐  ┌─────────────┐ │
    │  │ Module Gen   │  │ Studio   │  │ Studio      │ │
    │  │ Controller   │  │ Git Ctrl │  │ Deploy Ctrl │ │
    │  └──────┬───────┘  └────┬─────┘  └──────┬──────┘ │
    │         │               │                │        │
    │  ┌──────▼───────────────▼────────────────▼──────┐ │
    │  │        MongoDB (generation_events,           │ │
    │  │        generation_checkpoints, sessions)     │ │
    │  └──────────────────────────────────────────────┘ │
    └───────────────────────────────────────────────────┘