d4builder

A Diablo 4 build optimizer and webapp. Every number on the site is sourced from verified game data — no editorial opinion, no hand-authored content.

Season 12 (Season of Slaughter), patch 2.6.0.70982. 7 classes, 28 builds.

Quick start

git clone https://github.com/jabberwock/d4builder.git
cd d4builder/webapp
pnpm install
pnpm run dev

Open http://localhost:4321.

Project structure

d4builder/
  data/           # Frozen data pipeline + optimizer (read-only in normal use)
  webapp/         # Astro static site (the frontend)
  docs/           # Specs and design docs
  workers.yml     # Collab worker definitions (architect + webdev)

Data pipeline

The data/ directory contains the extraction scripts, verified databases, and the build optimizer. Data is frozen and verified — 49/49 regression tests pass. Do not modify unless you are deliberately updating the pipeline.

Key files

File	Contents
data/d4_stats.db	26-table SQLite: skills, damage, cooldowns, affixes, items, paragon, glyphs
data/maxroll_data.json	Maxroll game data dump (patch 2.6.0.70982)
data/passive_effects_d4data.json	322 tagged passive effects
data/optimizer_results.db	Build optimizer output — 28 builds, 4 per class

Running the optimizer

chmod -R u+w data/
python data/optimizer_v2.py
python data/verify_data.py   # must be 49/49
chmod -R u-w data/

Tiers are per-class (ranked relative to that class's top score), not global.

Refreshing maxroll data

data/fetch_maxroll.sh

Verification

python data/verify_data.py

49 hand-curated fixtures. Also wired into pre-commit hook, GitHub Actions, and make verify.

Webapp

Static Astro site consuming pre-baked JSON from the optimizer. Zero client JS by default. See docs/BUILD_DATA_SPEC.md for the data contract.

Astro + TypeScript (strict) + Tailwind. Cloudflare Pages. WCAG AA. Mobile-first, 375px baseline.

License

See LICENSE. Diablo IV assets are the property of Blizzard Entertainment. This is a fan project, not affiliated with or endorsed by Blizzard.