# Changelog

## v1.0.0 — 2026-02-28

Initial release of the EMBA Specialization Solver.

### Features

- **Optimization engine** — LP-based credit allocation solver with two modes:
  - **Maximize Count** — finds the largest feasible set of specializations, using ranking as tiebreaker
  - **Priority Order** — greedily adds specializations in user-ranked order
- **Course selection UI** — select one course per elective set across 12 sets (Spring, Summer, Fall terms)
- **Drag-and-drop specialization ranking** — reorder the 14 specializations by priority with touch and keyboard support
- **Decision tree analysis** — Web Worker enumerates remaining course combinations to compute ceiling outcomes per choice
- **Status tracking** — each specialization classified as achieved, achievable, missing required course, or unreachable
- **Mode comparison** — displays what the alternative optimization mode would produce
- **Credit bars and allocation breakdowns** — visual progress toward the 9-credit threshold with expandable per-course detail
- **Credit legend** — collapsible explainer for bars, badges, and limits
- **Required course labels** — courses that are prerequisites for a specialization show "Required for ..." labels
- **Algorithm explanations** — clear descriptions of how each optimization mode works
- **Skeleton loading** — placeholder UI while decision tree analysis runs
- **Auto-expand achieved specializations** — achieved specs show their credit breakdown by default
- **Responsive layout** — two-panel grid on desktop/tablet, single-column on mobile
- **Mobile floating banners** — top banner summarizes specialization statuses, bottom banner shows selection progress (N/12); both appear via IntersectionObserver and scroll to their sections on tap
- **CSS transitions and animations** — cross-fade course pin/unpin, credit bar width changes, status badge color transitions, expand/collapse panels, mode toggle switching, flash on status changes; all respect `prefers-reduced-motion`
- **State persistence** — rankings and selections saved to localStorage
- **Docker deployment** — multi-stage Dockerfile (Node 22 build → Nginx Alpine serve) with Docker Compose, gzip compression, SPA fallback routing, immutable cache headers for hashed assets, configurable port (default 8080)
- **Full test suite** — data integrity, feasibility solver, optimizer, and decision tree tests via Vitest

### Constraints Modeled

- Credit non-duplication (2.5 credits per course shared across specializations)
- Maximum 3 specializations (30 total credits, 9 required each)
- Required course prerequisites for 4 specializations
- Strategy S1/S2 tier system (at most 1 S2 course contributes to Strategy)
- Mutual exclusion from same-set conflicts