Data Packs & Modding Guide

Everything that shapes a run lives in JSON under dystrail-web/static/assets/data/ and ships with the WASM build. Editing these files lets you reskin or satirize the game without touching Rust.

Where things live

• journey/classic.json, journey/deep.json: base family configs (mpd ranges, partial ratio, wear/breakdown, crossings, guards).
• journey/overlays/*.json: strategy overlays that override family fields (Balanced, Aggressive, Conservative, ResourceManager).
• boss.json: distance gate, round count, stat weights, min/max chance, balanced bias (Classic bonus, Deep multiplier/bonus).
• crossings.json, camp.json, exec_orders.json, endgame.json: crossings odds/detours, camp actions, executive orders, endgame behavior.
• pacing.json, weather.json, vehicle.json: pace multipliers, weather impacts, vehicle wear/parts weights.
• personas.json, store.json, result.json, game.json: flavor, pricing, outcomes, and high-level game toggles.

How to make a new variant

1. Copy and edit JSON in static/assets/data/. Change numbers, names, or odds to your liking.
2. Run tests: just lint or cargo test --workspace --all-features --locked to ensure acceptance guards still pass.
3. Build the web client: just build-release (or let the CI build job run). The JSON is bundled into dystrail-web/dist.
4. Ship it: host dist (GitHub Pages via included workflows) and share the Play link/download.

Knobs to twist for satire

• Crossings: raise terminal, shrink pass, or make detour_days.max huge; tweak bribe bonuses/penalties.
• Travel feel: drop mpd_base, shrink mpd_min, or slash partial_ratio to 0.2 for a slog; invert for speed-runs.
• Breakdowns: spike breakdown.base and beta, or overweight a single part in part_weights.
• Endgame: set wear_multiplier to 0 to make finale trivial, or raise health_floor to punish.
• Boss: rename outcomes in boss.json, push distance_required up/down, or skew stat weights to reward pants hoarding.
• Economy/Flavor: rewrite store.json prices, camp.json actions, personas.json lines, weather.json names to match your satire.

Notes

• Keep guards reasonable if you want CI to stay green; otherwise relax them knowing tests may fail.
• Determinism is preserved as long as you keep the same RNG structure—changing JSON won’t break replays for a given seed, it only changes the outcomes via new numbers.