Parts become money, and the debug panel can hand you some

"0.34 parts" read as a fraction of something unnamed. It is a payment,
so it now looks like one: ¤34. The symbol is Unicode's generic currency
sign - it looks like money and is nobody's actual money, which is right
for a place whose banks are somebody else's problem.

The scale moves with it. FUNDS_PER_CONDITION fixes the exchange rate in
one place, so every balance number stays in the unit it is actually
about and how large the currency reads stays a presentational decision.
A supply run pays ¤34, an overhaul runs ¤200 to undo a crash's
permanent cost, and a full rebuild after a bad one is about a dozen
missions.

The debug panel gets ±¤ next to the existing condition levers, so the
workshop and the board can be exercised without first driving eight
missions to afford looking at them.

Save format bumped: quests.parts is now quests.funds.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

README.md

@@ -31,6 +31,7 @@ seeds may be numbers or words.
 | `R` | respawn the car — **does not** repair it |
 | `1`–`3` | accept a mission, when parked at a base |
 | `X` | give up the mission in hand, when parked at a base |
+| `C` | overhaul the car, when parked at a base |
 | `M` | sound on/off |
 | hold `R` | wipe the campaign and start over (5 seconds) |
 
@@ -254,19 +255,35 @@ sim: crossing a border, a road you have made notorious, a car past saving, or
 the front genuinely drifting your way, which is the brief's "the enemy has other
 priorities" said out loud without ever showing a number.
 
-### Rewards, and why repairs exist
+### Rewards, repairs, and the overhaul
 
-New targets pay `NOVELTY_BONUS` (1.8×) more than known ones. That multiplier is
+New targets pay `NOVELTY_BONUS` (1.8×) more than known ones. The currency sign
+is `¤` — Unicode's generic one, which looks like money and is nobody's actual
+money, for a place whose banks are somebody else's problem. That multiplier is
 the phase's tuning dial: if you never take the new target it is too low, and if
 you never take the known one it is too high.
 
-Payment is in **parts**, which repair the car — the only thing in the game that
-pushes condition back up. Repairs go to the worst subsystem first and stop at
+Payment is money, and money repairs the car. Repairs go to the worst subsystem first and stop at
 its **ceiling**, which drops permanently with every bit of damage taken
 (`PERMANENT_SHARE`, currently 30%). So a car can be patched back to what it is
 still capable of, but never to what it was. The HUD bars show this directly: `█`
 is current condition, `·` is what repairs could still reach, `×` is gone.
 
+Repairs happen automatically on hand-in, and they stop at the ceiling. Pressing
+`C` at a base does the other thing: an **overhaul**, which buys the *ceiling*
+itself back at 0.12 a point per ¤1, worst subsystem first. It deliberately does
+not touch the current level — it raises what the car could be, and ordinary
+repair still has to fill it in.
+
+The ceiling used to fall and nothing else: the only number in the game that
+moved one way, with no counterplay at any price. That reads less as a design
+pillar than as a punishment you cannot answer. Now decline is something you can
+fight, and what keeps it meaningful is the exchange rate rather than the
+impossibility — putting a car back to factory after one bad crash is about a
+dozen missions. Early on there is never a surplus to spend, so the option is
+invisible; it only becomes the thing to save for once the ceiling is what is
+actually holding you back.
+
 This is what gives the board's reward a reason to matter. Without an economy the
 choice between a safe route and a risky one has no stakes; with one, the risky
 job is what keeps the car alive a while longer.
@@ -278,7 +295,7 @@ Measured on the running game, a head-on into a building at 85 km/h comes back
 from Rapier as a single contact event of about **2.5e6 N** — twenty-five units
 of "impact" against the old 1e5 reference. Through the old coefficients that was
 123% of the chassis and 37% of its ceiling, gone, in one step, in a game whose
-missions pay about 0.3 parts. One crash ended the campaign, and the campaign had
+missions pay about ¤30. One crash ended the campaign, and the campaign had
 no way to end.
 
 Everything is now anchored to that measured figure, and damage is capped per
@@ -288,7 +305,7 @@ crash costs about 15% of the chassis and 5% of its ceiling.
 
 Baseline wear came down with it. Tyres shed 8e-5 per metre, so twelve clean
 kilometres took them from new to ruined while a two-kilometre round trip paid
-0.3 parts against 0.24 of condition spent. Driving perfectly barely broke even.
+¤30 against 0.24 of condition spent. Driving perfectly barely broke even.
 At a quarter of that, a typical mission spends about 0.06, so roughly two clean
 runs pay for one bad crash — enough slack to gamble with, not enough to ignore.
 
@@ -305,7 +322,7 @@ front line goes back to the enemy, through the same path a finished mission uses
 so the war moves for one reason only.
 
 The replacement is a real car — patched to its ceilings, because one that still
-needed the parts you do not have would just kill you again on the way out of the
+needed money you do not have would just kill you again on the way out of the
 yard — and every ceiling is 8% down on the one you wrote off. That is the
 ratchet applied at the one moment repairs cannot reach.
 
@@ -609,14 +626,15 @@ one place where "how broken the car is" turns into "how it drives".
 - **The car handles like a placeholder.** Suspension, grip, and engine numbers in
   `physics/physics.ts` and `sim/car.ts` are first guesses that pass a smoke test,
   not something tuned by feel. That tuning *is* Phase 0's verification gate.
-- **Wear rates are tuned against the parts economy** rather than by feel: a
+- **Wear rates are tuned against the economy** rather than by feel: a
   clean mission spends about a fifth of what it pays, and a hard crash costs
   roughly two clean missions. Those ratios are the dial, not the raw numbers.
 - **No interpolation** between physics steps. Fine at 60 Hz; revisit if the step
   rate changes.
-- **Repairs are automatic on hand-in.** Parts get spent the moment you report
-  back. The brief wants repair to be a physical, on-foot act with scavenged
-  parts; that is Phase 6.
+- **Repairs are automatic on hand-in.** Money gets spent the moment you report
+  back; the overhaul under `C` is the only deliberate spend. The brief wants
+  repair to be a physical, on-foot act with scavenged parts; that is still
+  deferred.
 - **The board's route preview assumes the shortest path.** If you drive a
   different way, the intel you were shown described a route you did not take.
   `findRoute` already accepts a cost function, so a "safest route" preview is a

src/debug.ts

@@ -16,6 +16,7 @@ import type { SceneView } from './render/scene';
 import type { PhysicsWorld } from './physics/physics';
 import type { LoopHandlers } from './core/loop';
 import { STEP } from './core/loop';
+import { CURRENCY } from './ui/currency';
 
 export interface CaptureOptions {
   /** Output width in pixels. Height follows 16:9. */
@@ -38,6 +39,9 @@ export interface DebugApi {
   teleport: (x: number, z: number) => void;
   condition: () => { level: { engine: number; tires: number; chassis: number } };
   setCondition: (level: number) => unknown;
+  /** Reads and writes the money in hand, for trying the workshop out. */
+  funds: () => number;
+  setFunds: (amount: number) => number;
 }
 
 /**
@@ -47,7 +51,10 @@ export interface DebugApi {
  * is a thing you want to do *while driving*, not while typing — so condition
  * gets buttons. Only ever mounted under `?debug=1`.
  */
-function mountPanel(debug: { nudgeCondition: (by: number) => unknown }, api: DebugApi): void {
+function mountPanel(
+  debug: { nudgeCondition: (by: number) => unknown; nudgeFunds: (by: number) => number },
+  api: DebugApi,
+): void {
   const panel = document.createElement('div');
   panel.id = 'debug-panel';
   panel.style.cssText = `
@@ -58,14 +65,20 @@ function mountPanel(debug: { nudgeCondition: (by: number) => unknown }, api: Deb
     border: 1px solid #2f3944; border-radius: 4px; padding: 8px 10px;
   `;
 
-  const readout = document.createElement('span');
-  readout.style.cssText = 'min-width: 74px; color: #8fa3b5;';
+  const reading = (width: number) => {
+    const span = document.createElement('span');
+    span.style.cssText = `min-width: ${width}px; color: #8fa3b5;`;
+    return span;
+  };
+  const carReadout = reading(74);
+  const fundsReadout = reading(66);
   const refresh = () => {
     const { engine, tires, chassis } = api.condition().level;
-    readout.textContent = `car ${(((engine + tires + chassis) / 3) * 100).toFixed(0)}%`;
+    carReadout.textContent = `car ${(((engine + tires + chassis) / 3) * 100).toFixed(0)}%`;
+    fundsReadout.textContent = `${CURRENCY}${Math.round(api.funds())}`;
   };
 
-  const button = (label: string, by: number) => {
+  const button = (label: string, apply: () => void) => {
     const element = document.createElement('button');
     element.textContent = label;
     element.style.cssText = `
@@ -74,7 +87,7 @@ function mountPanel(debug: { nudgeCondition: (by: number) => unknown }, api: Deb
       padding: 3px 9px;
     `;
     element.addEventListener('click', () => {
-      debug.nudgeCondition(by);
+      apply();
       refresh();
       // Keep the keyboard on the game, or space starts pressing this button.
       element.blur();
@@ -83,9 +96,14 @@ function mountPanel(debug: { nudgeCondition: (by: number) => unknown }, api: Deb
   };
 
   panel.append(document.createTextNode('debug'));
-  button('−', -0.15);
-  button('+', +0.15);
-  panel.append(readout);
+  button('−', () => debug.nudgeCondition(-0.15));
+  button('+', () => debug.nudgeCondition(+0.15));
+  panel.append(carReadout);
+  // Money, so the workshop and the board can be exercised without first
+  // driving eight missions to afford looking at them.
+  button('−¤', () => debug.nudgeFunds(-50));
+  button('+¤', () => debug.nudgeFunds(+50));
+  panel.append(fundsReadout);
   document.body.append(panel);
 
   refresh();
@@ -168,6 +186,12 @@ export function exposeDebug(api: DebugApi): void {
       const now = api.condition().level;
       return api.setCondition((now.engine + now.tires + now.chassis) / 3 + by);
     },
+    /** Money in hand. */
+    funds: api.funds,
+    setFunds: api.setFunds,
+    nudgeFunds(by: number) {
+      return api.setFunds(api.funds() + by);
+    },
     info: api.info,
     state: api.state,
     three: THREE,

src/main.ts

@@ -61,6 +61,7 @@ import { createHud } from './ui/hud';
 import { createBoard } from './ui/board';
 import { createAudio } from './audio/audio';
 import { CAR, WHEELS } from './carSpec';
+import { CURRENCY } from './ui/currency';
 
 /** What the wheel reads while nobody is holding it. */
 const DEAD_HANDS = {
@@ -557,14 +558,14 @@ async function boot() {
       if (base && stopped && cmd.overhaul) {
         if (!canOverhaul(condition)) {
           say('Nothing to rebuild. She is as good as she ever was.', 4);
-        } else if (quests.parts < 0.05) {
-          say('No parts to work with. Bring something back first.', 4);
+        } else if (quests.funds < 1) {
+          say(`Nothing to pay with. Bring something back first.`, 4);
         } else {
           const before = condition.ceiling;
-          const done = overhaul(condition, quests.parts);
-          const spent = quests.parts - done.unused;
+          const done = overhaul(condition, quests.funds);
+          const spent = quests.funds - done.unused;
           condition = done.condition;
-          quests.parts = done.unused;
+          quests.funds = done.unused;
           const gained =
             condition.ceiling.engine +
             condition.ceiling.tires +
@@ -577,7 +578,7 @@ async function boot() {
             say('Nothing worth stripping her down for. She is near enough new.', 4);
           } else {
             say(
-              `Stripped and rebuilt. ${spent.toFixed(2)} parts, and she will take ` +
+              `Stripped and rebuilt. ${CURRENCY}${spent.toFixed(0)}, and she will take ` +
                 `${(gained * 100).toFixed(0)}% more than she would have.`,
               7,
             );
@@ -690,13 +691,13 @@ async function boot() {
           // The line moves because of what the player did. They are not told by
           // how much — they find out by going back and looking.
           applyMissionImpact(front, event.impact);
-          const outcome = repair(condition, quests.parts);
-          const spent = quests.parts - outcome.unused;
+          const outcome = repair(condition, quests.funds);
+          const spent = quests.funds - outcome.unused;
           condition = outcome.condition;
-          quests.parts = outcome.unused;
+          quests.funds = outcome.unused;
           say(
-            spent > 0.001
-              ? `Handed in. Repairs used ${spent.toFixed(2)} parts.`
+            spent > 0.5
+              ? `Handed in. Repairs took ${CURRENCY}${spent.toFixed(0)}.`
               : 'Handed in. Nothing left worth repairing.',
           );
           // Checkpoint: a finished run is the most expensive thing to lose.
@@ -723,7 +724,7 @@ async function boot() {
       );
       if (found?.kind === 'appeared') say(found.opportunity.hail, 7);
       else if (found?.kind === 'helped') {
-        quests.parts += found.opportunity.reward;
+        quests.funds += found.opportunity.reward;
         if (found.opportunity.impact > 0) applyMissionImpact(front, found.opportunity.impact);
         say(found.opportunity.done, 7);
         persistence.checkpoint(elapsed, snapshot());
@@ -1007,7 +1008,7 @@ async function boot() {
         completed: quests.completed,
         failed: quests.failed,
         kia,
-        parts: quests.parts,
+        funds: quests.funds,
         notice: elapsed < noticeUntil ? notice : '',
         resetProgress: resetHeld / RESET_HOLD_SECONDS,
         muted: audio.muted,
@@ -1043,6 +1044,12 @@ async function boot() {
         };
         return condition;
       },
+      funds: () => quests.funds,
+      /** Set the money in hand. Nothing in the game hands out money like this. */
+      setFunds(amount: number) {
+        quests.funds = Math.max(0, amount);
+        return quests.funds;
+      },
       teleport(x, z) {
         physics.chassis.setTranslation({ x, y: 1.4, z }, true);
         physics.chassis.setLinvel({ x: 0, y: 0, z: 0 }, true);
@@ -1053,7 +1060,7 @@ async function boot() {
         control,
         segment: currentSegment,
         onTarmac,
-        parts: quests.parts,
+        funds: quests.funds,
         completed: quests.completed,
         failed: quests.failed,
         kia,

src/sim/car.ts

@@ -42,6 +42,17 @@ export interface Handling {
   steeringPull: number;
 }
 
+/**
+ * Money that buys one full point of a subsystem's condition.
+ *
+ * The sim thinks in condition, which runs 0..1; the player thinks in what is in
+ * their pocket. Fixing the exchange rate here lets every balance number stay in
+ * the units it is actually about, and keeps the scale of the currency a purely
+ * presentational decision — ¤34 for a supply run reads as a payment, where 0.34
+ * read as a fraction of something unnamed.
+ */
+export const FUNDS_PER_CONDITION = 100;
+
 export const SUBSYSTEMS = ['engine', 'tires', 'chassis'] as const;
 
 export const freshCondition = (): CarCondition => ({
@@ -129,7 +140,7 @@ const PERMANENT_SHARE = 0.3;
  * back as a single event of ~2.5e6 N. Against the old 1e5 reference that was 25
  * units of impact, which through the coefficients below wrote off the chassis —
  * and 37% of its ceiling — in one hit, on a car whose whole economy pays about
- * 0.3 parts a mission. One crash ended the campaign.
+ * ¤30 a mission. One crash ended the campaign.
  *
  * At 1.6e7 the same crash reads as 0.154 impact. What that then costs is set by
  * the coefficients below, and they are deliberately brutal: a proper head-on
@@ -158,16 +169,16 @@ const MAX_DAMAGE_PER_STEP = 0.85;
  * Returns a new condition.
  *
  * Baseline wear is deliberately quicker than real life so decline is legible
- * within a session, but it has to stay inside what the parts economy can pay
+ * within a session, but it has to stay inside what the economy can pay
  * for. The old figures did not: tyres shed 8e-5 per metre, so twelve clean
  * kilometres — no crashes at all — took them from new to ruined, while a
- * two-kilometre round trip paid about 0.3 parts against 0.24 of condition
+ * two-kilometre round trip paid about ¤30 against 0.24 of condition
  * spent. Driving perfectly barely broke even and one knock put you permanently
  * behind, which is a decline with no way to arrest it rather than a decision
  * about how hard to push the car.
  *
  * At a quarter of that a typical mission spends about 0.06 condition against
- * ~0.3 parts earned, so roughly two clean runs pay for one bad crash. That is
+ * ~¤30 earned, so roughly two clean runs pay for one bad crash. That is
  * the ratio the whole risk/reward loop rests on: enough slack to gamble with,
  * not enough to ignore.
  */
@@ -192,12 +203,12 @@ export function applyWear(c: CarCondition, w: WearInput): CarCondition {
 }
 
 /**
- * Spends parts on the worst subsystem first, never above its ceiling.
+ * Spends money on the worst subsystem first, never above its ceiling.
  * Returns the new condition and whatever could not be used.
  */
-export function repair(c: CarCondition, parts: number): { condition: CarCondition; unused: number } {
+export function repair(c: CarCondition, funds: number): { condition: CarCondition; unused: number } {
   const level = { ...c.level };
-  let remaining = parts;
+  let remaining = funds / FUNDS_PER_CONDITION;
 
   // Worst-first: a car with one ruined subsystem drives worse than one that is
   // evenly tired, so that is where a scarce part belongs.
@@ -213,21 +224,21 @@ export function repair(c: CarCondition, parts: number): { condition: CarConditio
     remaining -= spend;
   }
 
-  return { condition: { level, ceiling: c.ceiling }, unused: remaining };
+  return { condition: { level, ceiling: c.ceiling }, unused: remaining * FUNDS_PER_CONDITION };
 }
 
 /**
- * Ceiling bought back per part spent on an overhaul.
+ * Ceiling bought back per unit of currency spent on an overhaul.
  *
  * Deliberately a bad rate next to an ordinary repair, which buys a full point
  * of condition per part. Rebuilding what a subsystem is *capable* of is not
  * patching it up; it is the expensive thing you do when patching has stopped
  * helping.
  *
- * At 0.12 a crash's permanent cost (~0.24 of the chassis ceiling) takes two
- * parts to undo, or about seven missions.
+ * A crash's permanent cost (~0.24 of the chassis ceiling) takes about ¤200 to
+ * undo, or seven missions' pay.
  */
-const CEILING_PER_PART = 0.12;
+const CEILING_PER_FUND = 0.12 / FUNDS_PER_CONDITION;
 
 /**
  * Spends parts on raising the ceiling itself, worst subsystem first.
@@ -244,9 +255,9 @@ const CEILING_PER_PART = 0.12;
  * and there is never a surplus; it is only once the ceiling is what is actually
  * holding you back that parts start piling up with nowhere else to go.
  */
-export function overhaul(c: CarCondition, parts: number): { condition: CarCondition; unused: number } {
+export function overhaul(c: CarCondition, funds: number): { condition: CarCondition; unused: number } {
   const ceiling = { ...c.ceiling };
-  let remaining = parts;
+  let remaining = funds;
 
   for (let pass = 0; pass < SUBSYSTEMS.length && remaining > OVERHAUL_EPSILON; pass++) {
     const worst = [...SUBSYSTEMS]
@@ -255,11 +266,11 @@ export function overhaul(c: CarCondition, parts: number): { condition: CarCondit
     if (!worst) break;
 
     const room = 1 - ceiling[worst];
-    const needed = room / CEILING_PER_PART;
+    const needed = room / CEILING_PER_FUND;
     // Snap when the spend covers the whole gap, rather than landing a
     // rounding error short of factory and reporting the car as still rebuildable.
     ceiling[worst] =
-      remaining >= needed ? 1 : clamp01(ceiling[worst] + remaining * CEILING_PER_PART);
+      remaining >= needed ? 1 : clamp01(ceiling[worst] + remaining * CEILING_PER_FUND);
     remaining -= Math.min(needed, remaining);
   }
 

src/sim/kia.test.ts

@@ -90,7 +90,7 @@ describe('what a death costs', () => {
     expect(quests.active).toBeNull();
     expect(quests.completed).toBe(0);
     expect(quests.failed).toBe(1);
-    expect(quests.parts).toBe(0);
+    expect(quests.funds).toBe(0);
   });
 
   it('is a setback, not a campaign reversal', () => {

src/sim/opportunities.ts

@@ -19,7 +19,7 @@ export interface Opportunity {
   kind: OpportunityKind;
   x: number;
   z: number;
-  /** Parts paid for stopping. */
+  /** Money paid for stopping. */
   reward: number;
   /** Whether helping shifts the front at all. */
   impact: number;
@@ -59,7 +59,7 @@ const FLAVOUR: Record<OpportunityKind, { hail: string[]; done: string[]; reward:
       'They can walk from here. They did not ask your name, which was kind of them.',
       'Patched up as far as anything in your boot allows. They point you at a road they say is quiet.',
     ],
-    reward: 0.06,
+    reward: 6,
     impact: 3,
   },
   contact: {
@@ -71,7 +71,7 @@ const FLAVOUR: Record<OpportunityKind, { hail: string[]; done: string[]; reward:
       'A package changes hands. Neither of you says anything worth repeating.',
       'They pass you a name and a road number, then walk off before you can ask.',
     ],
-    reward: 0.14,
+    reward: 14,
     impact: 9,
   },
   wreck: {
@@ -83,7 +83,7 @@ const FLAVOUR: Record<OpportunityKind, { hail: string[]; done: string[]; reward:
       'You strip what will fit in the boot and leave the rest to rust.',
       'Two good parts and a lot of scrap. It will do.',
     ],
-    reward: 0.11,
+    reward: 11,
     impact: 0,
   },
 };

src/sim/quests.test.ts

@@ -208,7 +208,7 @@ describe('mission lifecycle', () => {
     expect(done?.kind).toBe('completed');
     expect(state.active).toBeNull();
     expect(state.completed).toBe(1);
-    expect(state.parts).toBeGreaterThan(0);
+    expect(state.funds).toBeGreaterThan(0);
   });
 
   it('accepts a hand-in at any base, so a blocked road home cannot strand you', () => {

src/sim/quests.ts

@@ -73,7 +73,7 @@ export interface Offer {
   novel: boolean;
   route: Route;
   intel: RouteIntel;
-  /** Parts awarded on hand-in. */
+  /** Money paid on hand-in. */
   reward: number;
   /**
    * How far this job pushes the front line, in metres. The brief asks for
@@ -97,8 +97,8 @@ export interface QuestState {
   completed: number;
   /** Jobs dropped or lost with the car. Counted separately: they are not runs. */
   failed: number;
-  /** Unspent repair parts. */
-  parts: number;
+  /** Money in hand, spent on repairs and overhauls. */
+  funds: number;
   nextId: number;
 }
 
@@ -106,7 +106,7 @@ export const createQuests = (): QuestState => ({
   active: null,
   completed: 0,
   failed: 0,
-  parts: 0,
+  funds: 0,
   nextId: 1,
 });
 
@@ -138,11 +138,11 @@ const CARGO_FRAGILITY = 1.4e-6;
  * known targets are never taken, too high.
  */
 const NOVELTY_BONUS = 1.8;
-const PARTS_PER_KM = 0.1;
+const PAY_PER_KM = 10;
 
 /** Exported so the novelty premium can be tested on like for like. */
 export function rewardFor(type: MissionType, route: Route, novel: boolean): number {
-  const base = 0.08 + (route.length / 1000) * PARTS_PER_KM;
+  const base = 8 + (route.length / 1000) * PAY_PER_KM;
   return base * (novel ? NOVELTY_BONUS : 1) * MISSION_SHAPE[type].reward;
 }
 
@@ -232,7 +232,7 @@ export type QuestEvent =
   | { kind: 'arrived' }
   | { kind: 'worked'; type: MissionType }
   | { kind: 'cargoDamaged'; cargo: number }
-  | { kind: 'completed'; parts: number; impact: number; cargo: number };
+  | { kind: 'completed'; paid: number; impact: number; cargo: number };
 
 /** Advances the active mission. Returns whatever just happened, if anything. */
 export function stepQuest(state: QuestState, step: QuestStep): QuestEvent | null {
@@ -281,8 +281,8 @@ export function stepQuest(state: QuestState, step: QuestStep): QuestEvent | null
     const paid = quest.reward * (MISSION_SHAPE[quest.type].cargoHome ? quest.cargo : 1);
     state.active = null;
     state.completed++;
-    state.parts += paid;
-    return { kind: 'completed', parts: paid, impact: quest.impact * quest.cargo, cargo: quest.cargo };
+    state.funds += paid;
+    return { kind: 'completed', paid, impact: quest.impact * quest.cargo, cargo: quest.cargo };
   }
 
   return damaged ? { kind: 'cargoDamaged', cargo: quest.cargo } : null;

src/sim/save.test.ts

@@ -29,7 +29,7 @@ function played(): Snapshot {
   applyMissionImpact(front, 18);
   quests.completed = 3;
   quests.failed = 1;
-  quests.parts = 0.42;
+  quests.funds = 42;
   quests.nextId = 7;
 
   return {
@@ -78,7 +78,7 @@ describe('save round trip', () => {
     expect(restored.heat.level).toEqual(source.heat.level);
     expect(restored.quests.completed).toBe(3);
     expect(restored.quests.failed).toBe(1);
-    expect(restored.quests.parts).toBeCloseTo(0.42, 9);
+    expect(restored.quests.funds).toBeCloseTo(42, 9);
     // A campaign's history of written-off cars has to outlive the tab, or the
     // ratchet the KIA rule exists to drive resets every time you close it.
     expect(restored.kia).toBe(2);

src/sim/save.ts

@@ -16,7 +16,7 @@ import type { Intel } from './intel';
 import type { Boundaries, Front } from './regions';
 import type { ActiveQuest, QuestState } from './quests';
 
-export const SAVE_VERSION = 3;
+export const SAVE_VERSION = 4;
 
 export interface CarSnapshot {
   position: [number, number, number];
@@ -47,7 +47,7 @@ export interface SaveData {
     active: ActiveQuest | null;
     completed: number;
     failed: number;
-    parts: number;
+    funds: number;
     nextId: number;
   };
   /** Times the car has been written off underneath the player. */
@@ -89,7 +89,7 @@ export function serialise(s: Snapshot): SaveData {
       active: s.quests.active,
       completed: s.quests.completed,
       failed: s.quests.failed,
-      parts: s.quests.parts,
+      funds: s.quests.funds,
       nextId: s.quests.nextId,
     },
     kia: s.kia,
@@ -146,7 +146,7 @@ export function apply(data: SaveData, into: Snapshot): void {
   into.quests.active = data.quests.active;
   into.quests.completed = data.quests.completed;
   into.quests.failed = data.quests.failed;
-  into.quests.parts = data.quests.parts;
+  into.quests.funds = data.quests.funds;
   into.quests.nextId = data.quests.nextId;
   into.kia = data.kia;
 }

src/sim/sim.test.ts

@@ -3,6 +3,7 @@ import { generateWorld } from './world';
 import {
   applyWear,
   canOverhaul,
+  FUNDS_PER_CONDITION,
   deriveHandling,
   freshCondition,
   overhaul,
@@ -151,30 +152,31 @@ describe('repair', () => {
     const c = damaged();
     expect(c.ceiling.chassis).toBeLessThan(1);
     // No amount of parts can undo it.
-    const restored = repair(c, 99).condition;
+    const restored = repair(c, 9999).condition;
     expect(restored.level.chassis).toBeLessThan(1);
     expect(restored.level.chassis).toBeCloseTo(c.ceiling.chassis, 6);
   });
 
   it('never lifts a subsystem above its ceiling', () => {
     const c = damaged();
-    const restored = repair(c, 99).condition;
+    const restored = repair(c, 9999).condition;
     for (const part of SUBSYSTEMS) {
       expect(restored.level[part]).toBeLessThanOrEqual(restored.ceiling[part] + 1e-9);
     }
   });
 
   it('hands back parts it could not use', () => {
-    const { unused } = repair(freshCondition(), 5);
-    expect(unused).toBeCloseTo(5, 6);
+    const { unused } = repair(freshCondition(), 500);
+    expect(unused).toBeCloseTo(500, 6);
   });
 
-  it('spends a scarce part on the worst subsystem', () => {
+  it('spends scarce money on the worst subsystem', () => {
     const c: CarCondition = {
       level: { engine: 0.9, tires: 0.2, chassis: 0.8 },
       ceiling: { engine: 1, tires: 1, chassis: 1 },
     };
-    const restored = repair(c, 0.1).condition;
+    // A tenth of a point of condition, in what the player actually carries.
+    const restored = repair(c, 0.1 * FUNDS_PER_CONDITION).condition;
     expect(restored.level.tires).toBeCloseTo(0.3, 6);
     expect(restored.level.engine).toBe(0.9);
   });
@@ -186,7 +188,7 @@ describe('repair', () => {
       for (let i = 0; i < 30; i++) {
         c = applyWear(c, { dt: 1 / 60, distance: 3, throttle: 1, impactForce: 2e4 });
       }
-      c = repair(c, 99).condition;
+      c = repair(c, 9999).condition;
       // Fully repaired every cycle, and still worse off every cycle.
       expect(c.level.chassis).toBeCloseTo(c.ceiling.chassis, 6);
       expect(c.ceiling.chassis).toBeLessThan(previousCeiling);
@@ -255,7 +257,7 @@ describe('overhaul', () => {
     let c = freshCondition();
     for (let i = 0; i < 6; i++) {
       c = applyWear(c, { dt: 1 / 60, distance: 0.4, throttle: 0, impactForce: 1.2e6 });
-      c = repair(c, 99).condition;
+      c = repair(c, 9999).condition;
     }
     return c;
   };
@@ -263,13 +265,13 @@ describe('overhaul', () => {
   it('is the one thing that can push a ceiling back up', () => {
     const c = battered();
     expect(c.ceiling.chassis).toBeLessThan(0.9);
-    const after = overhaul(c, 3).condition;
+    const after = overhaul(c, 300).condition;
     expect(after.ceiling.chassis).toBeGreaterThan(c.ceiling.chassis);
   });
 
   it('leaves the level alone — it buys capability, not condition', () => {
     const c = battered();
-    const after = overhaul(c, 3).condition;
+    const after = overhaul(c, 300).condition;
     expect(after.level).toEqual(c.level);
     // Which is what makes it a *second* spend: the room it opens up still has
     // to be filled by ordinary repair.
@@ -281,7 +283,7 @@ describe('overhaul', () => {
       level: { engine: 0.5, tires: 0.5, chassis: 0.5 },
       ceiling: { engine: 0.9, tires: 0.5, chassis: 0.8 },
     };
-    const after = overhaul(c, 1).condition;
+    const after = overhaul(c, 100).condition;
     expect(after.ceiling.tires).toBeGreaterThan(0.5);
     expect(after.ceiling.engine).toBe(0.9);
   });
@@ -291,21 +293,21 @@ describe('overhaul', () => {
       level: { engine: 0.5, tires: 0.5, chassis: 0.5 },
       ceiling: { engine: 0.5, tires: 0.5, chassis: 0.5 },
     };
-    const repaired = repair({ ...c, ceiling: { engine: 1, tires: 1, chassis: 1 } }, 1).condition;
-    const rebuilt = overhaul(c, 1).condition;
+    const repaired = repair({ ...c, ceiling: { engine: 1, tires: 1, chassis: 1 } }, 50).condition;
+    const rebuilt = overhaul(c, 50).condition;
     const repairedGain = repaired.level.engine + repaired.level.tires + repaired.level.chassis - 1.5;
     const rebuiltGain = rebuilt.ceiling.engine + rebuilt.ceiling.tires + rebuilt.ceiling.chassis - 1.5;
     expect(rebuiltGain).toBeLessThan(repairedGain);
   });
 
   it('never goes past factory, and hands back what it could not use', () => {
-    const { condition, unused } = overhaul(battered(), 99);
+    const { condition, unused } = overhaul(battered(), 9999);
     for (const part of SUBSYSTEMS) expect(condition.ceiling[part]).toBeCloseTo(1, 9);
     expect(unused).toBeGreaterThan(0);
     expect(canOverhaul(condition)).toBe(false);
   });
 
-  it('costs about seven missions to undo one crash', () => {
+  it('costs a run of missions to undo one crash, not one and not fifty', () => {
     // The exchange rate is the whole design. Free and the ceiling means
     // nothing; unaffordable and it is the ratchet it was before.
     const crashed = applyWear(freshCondition(), {
@@ -314,15 +316,17 @@ describe('overhaul', () => {
       throttle: 0,
       impactForce: 2.47e6,
     });
-    const lost = 1 - crashed.ceiling.chassis;
-    let spent = 0;
+    const MISSION_PAY = 30;
+    let missions = 0;
     let c = crashed;
-    while (c.ceiling.chassis < 1 - 1e-9 && spent < 50) {
-      c = overhaul(c, 0.3).condition; // one mission's pay
-      spent += 0.3;
+    while (canOverhaul(c) && missions < 200) {
+      c = overhaul(c, MISSION_PAY).condition;
+      missions++;
     }
-    expect(lost).toBeGreaterThan(0.15);
-    expect(spent / 0.3).toBeGreaterThan(4);
-    expect(spent / 0.3).toBeLessThan(12);
+    expect(1 - crashed.ceiling.chassis).toBeGreaterThan(0.15);
+    // Putting the whole car back to factory after one bad crash: an evening's
+    // work, not a weekend's and not a single job.
+    expect(missions).toBeGreaterThan(6);
+    expect(missions).toBeLessThan(20);
   });
 });

src/sim/texture.test.ts

@@ -82,7 +82,7 @@ function runMission(type: MissionType, impactPerStep = 0) {
     speed: 0,
     impactForce: 0,
   });
-  return { done, cargo, parts: state.parts };
+  return { done, cargo, paid: state.funds };
 }
 
 describe('carrying cargo home', () => {
@@ -96,13 +96,13 @@ describe('carrying cargo home', () => {
     const clean = runMission('retrieval');
     const rough = runMission('retrieval', 4e4);
     expect(rough.cargo).toBeLessThan(clean.cargo);
-    expect(rough.parts).toBeLessThan(clean.parts);
+    expect(rough.paid).toBeLessThan(clean.paid);
   });
 
   it('leaves other mission types alone, however hard you crash', () => {
     const rough = runMission('supply', 8e4);
     expect(rough.cargo).toBe(1);
-    expect(rough.parts).toBeCloseTo(runMission('supply').parts, 9);
+    expect(rough.paid).toBeCloseTo(runMission('supply').paid, 9);
   });
 });
 

src/ui/board.ts

@@ -1,6 +1,7 @@
 import type { Base } from '../sim/bases';
 import type { HeatLevel } from '../sim/heat';
 import { MISSION_SHAPE, type MissionType, type Offer } from '../sim/quests';
+import { money } from './currency';
 
 /**
  * What each job actually asks of you, in the words the people asking would use.
@@ -51,7 +52,7 @@ function describe(offer: Offer): string {
  * discovers it exists.
  */
 const OVERHAUL_FOOTER =
-  ' · <span class="key">[C]</span> overhaul — spend parts on what she is capable of';
+  ' · <span class="key">[C]</span> overhaul — spend on what she is capable of';
 
 export function createBoard() {
   const el = document.createElement('div');
@@ -92,7 +93,7 @@ export function createBoard() {
             ${MISSION_SHAPE[offer.type].label} —
             ${offer.novel ? '<span class="novel">new target</span>' : 'known target'}
             · ${(offer.route.length / 1000).toFixed(1)} km
-            · ${offer.reward.toFixed(2)} parts
+            · ${money(offer.reward)}
             <div class="meta">${BRIEFING[offer.type]}</div>
             <div class="meta">${describe(offer)}</div>
           </li>`,

src/ui/currency.ts

@@ -0,0 +1,12 @@
+/**
+ * What the insurgency pays in.
+ *
+ * `¤` is Unicode's generic currency sign: it looks like money and is not any
+ * particular country's money, which is exactly right for a place whose banks
+ * are somebody else's problem. Kept here rather than inlined so the whole game
+ * agrees on it, and so it is one edit if it ever wants a name.
+ */
+export const CURRENCY = '¤';
+
+/** Money as the player reads it. Whole units — nobody counts small change here. */
+export const money = (amount: number): string => `${CURRENCY}${Math.round(amount)}`;

src/ui/hud.ts

@@ -1,4 +1,5 @@
 import { SUBSYSTEMS, type CarCondition } from '../sim/car';
+import { money } from './currency';
 import type { HeatLevel } from '../sim/heat';
 import { MISSION_SHAPE, type MissionType } from '../sim/quests';
 import type { Control } from '../sim/regions';
@@ -54,7 +55,7 @@ export interface HudModel {
   failed: number;
   /** Cars written off underneath the player. */
   kia: number;
-  parts: number;
+  funds: number;
   notice: string;
   /** 0..1 toward wiping the campaign, while R is held. */
   resetProgress: number;
@@ -141,7 +142,7 @@ export function createHud(seed: number, debug = false) {
             `${part.padEnd(7)} ${bar(condition.level[part], condition.ceiling[part])} ` +
             `${(condition.level[part] * 100).toFixed(0)}%`,
         ),
-        `parts   ${model.parts.toFixed(2)}   runs ${model.completed}` +
+        `funds   ${money(model.funds).padEnd(8)} runs ${model.completed}` +
           (model.failed > 0 ? `   lost ${model.failed}` : '') +
           // Cars are counted, not lives. There is no stock of them to run out
           // of; the number is there so a long campaign reads as a history.