inter-hub-haskell/CLAUDE.md

# CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

## Project Overview

**inter-hub** is the reference implementation of the **Interaction Hub Framework (IHF)** — a governed, observable interaction substrate for hub-based AI-enabled software systems. It treats every UI element as a governed artifact, creating a full traceability chain from rendered widget → user interaction → structured feedback → requirement candidate → decision record → implementation change → observed outcome.

**Current state:** Phases 1–3 complete. Phase 4 (Outcome Observation and Antifragility Loop) is the active implementation target.

For situational context, read `SCOPE.md`. For architecture depth, read `specs/InteractionHubFrameworkSpecification_v0.1.md`.

## Stack

- **IHP** (Integrated Haskell Platform) v1.5 — full-stack Haskell web framework, server-rendered + optional realtime
- **Haskell** (GHC 9.10) — strongly typed, functional
- **PostgreSQL** — canonical datastore, managed via Nix (no manual DB setup)
- **Nix / devenv** — reproducible environment
- **Tailwind CSS** — see `specs/TailwindForInteractionHubs_v0.2.md` for IHF-specific conventions

## Development Setup

Requires Determinate Nix + direnv:

```bash
# One-time environment setup
curl --proto '=https' --tlsv1.2 -sSf -L https://install.determinate.systems/nix | sh
nix profile install nixpkgs#ihp-new
nix profile add nixpkgs#direnv

# Bootstrap IHP project (Phase 1, Task T01)
ihp-new inter-hub
cd inter-hub
devenv up
```

After `devenv up`:
- App server: `http://localhost:8000`
- IHP IDE + Schema Designer: `http://localhost:8001`

## Key Commands

```bash
devenv up          # Start dev environment (app + postgres + file watchers)
migrate            # Run pending migrations
test               # Run tests (auto-creates temp Postgres DB)
make static/prod.js static/prod.css   # Production asset bundle
deploy-to-nixos production            # NixOS deploy
```

Schema editing: use the IHP IDE at `localhost:8001` or edit `Application/Schema.sql` directly. Code generation via `localhost:8001/Generators`.

## Architecture

### Core Domain Model (Phase 1)

| Entity | Role |
|--------|------|
| `Hub` | Bounded domain of responsibility (Dev Hub, Ops Hub, etc.) |
| `Widget` | Smallest semantically governable interaction unit with stable ID |
| `WidgetVersion` | Version history of widget definitions |
| `InteractionEvent` | Recorded user/agent interaction (viewed, clicked, submitted, etc.) — **append-only** (enforced by PostgreSQL trigger) |
| `Annotation` | Structured comment attached to a widget with category |
| `ViewContext` | Logical location in the UI |
| `CapabilityReference` | Link to hub capability |

### Traceability Chain

```
Widget → InteractionEvent / Annotation
       → RequirementCandidate (Phase 2)
       → DecisionRecord (Phase 3)
       → ImplementationChange → DeploymentRecord → OutcomeSignal
```

### IHP Conventions

- Controllers live in `Web/Controller/`, views in `Web/View/`, types in `Web/Types.hs`
- Schema changes go in `Application/Schema.sql`, then generate with IHP IDE
- Use `AutoRefresh` for operator dashboards (server push on DB change) — not DataSync or Server-Side Components in Phase 1
- See `docs/ihp-ihf-mapping.md` for how IHP capabilities map to IHF requirements

### Widget Envelope

Every rendered widget wraps its HSX in a `widgetEnvelope` helper (Task T08) that injects the stable `widget-id` and `view-context` attributes, enabling client-side event capture without coupling to implementation.

## UI Conventions

All hub interfaces follow the Tailwind layer model in `specs/TailwindForInteractionHubs_v0.2.md`:

```
Semantic Role → Visual Primitive → Tailwind Token → Screen Composition
```

Key rules:
- Every interactive element belongs to a named semantic role (`action-primary`, `nav-item`, `data-cell`, etc.)
- Use spacing rhythm from the spec; do not invent ad-hoc spacing
- State cues (hover, active, disabled, error) follow the defined color roles

## Required Environment Variables

| Variable | Purpose |
|----------|---------|
| `IHP_SESSION_SECRET` | Session encryption key |
| `DATABASE_URL` | Postgres connection string |
| `IHP_BASEURL` | External URL (e.g., `https://example.com`) |

## Active Workplan

Phase 4 work is tracked in `workplans/IHUB-WP-0004-ihf-phase4-outcome-observation-and-antifragility.md` (9 tasks, T01–T09). Use `/ralph-workplan workplans/IHUB-WP-0004-ihf-phase4-outcome-observation-and-antifragility.md` to drive implementation loops.

Phase 4 exit criteria:
- The platform can determine whether a change improved outcomes
- Recurrent friction becomes visible
- The system supports evidence-based UI evolution

Completed workplans: IHUB-WP-0001 (Phase 1), IHUB-WP-0002 (Phase 2), IHUB-WP-0003 (Phase 3).

## Key Reference Docs

| File | Purpose |
|------|---------|
| `SCOPE.md` | Situational guide — in/out of scope, terminology, entry points |
| `specs/InteractionHubFrameworkSpecification_v0.1.md` | Full IHF spec (8 phases, risks, design principles) |
| `specs/TailwindForInteractionHubs_v0.2.md` | Agent-optimized Tailwind coding guide |
| `docs/ihp-overview.md` | IHP v1.5 fundamentals and dev workflow |
| `docs/ihp-data-and-queries.md` | Schema design, auto-generated types, query builder, migrations |
| `docs/ihp-controllers-views-forms.md` | Controller patterns, HSX, forms, validation, auth |
| `docs/ihp-realtime.md` | AutoRefresh vs DataSync vs HTMX decision guide |
| `docs/ihp-ihf-mapping.md` | IHP capability → IHF requirement mapping with schema templates |

## Related Repositories

- `hub-core` — planned shared base package for domain/capability registration
- `the-custodian` — State Hub (decision records, workstreams) that IHF governance integrates with
- Downstream consumers: `dev-hub`, `ops-hub`, `fin-hub`