diff --git a/server/src/systems/__tests__/industryIntegration.test.ts b/server/src/systems/__tests__/industryIntegration.test.ts
new file mode 100644
index 0000000..ceee97d
--- /dev/null
+++ b/server/src/systems/__tests__/industryIntegration.test.ts
@@ -0,0 +1,109 @@
+import { describe, it, expect } from 'vitest';
+import { World } from '../../ecs/World.js';
+import { GameMap } from '../../map/GameMap.js';
+import { industrySystem } from '../industrySystem.js';
+import { craftingSystem, type CraftingState } from '../craftingSystem.js';
+import { buildingSystem, type BuildingState, type StructureData } from '../buildingSystem.js';
+import { gatheringSystem, type GatheringState } from '../gatheringSystem.js';
+import { dropoffSystem } from '../dropoffSystem.js';
+import { RecipeRegistry } from '../../industry/recipeRegistry.js';
+import type { Needs, Movement, NPCBrain, Position, Stats, StatModifiers } from '@dflike/shared';
+
+function createTestWorld(): { world: World; map: GameMap } {
+  const world = new World();
+  world.setSingleton('recipeRegistry', RecipeRegistry.createDefault());
+  const map = new GameMap(20, 20);
+  map.resourceTiles = [
+    { x: 3, y: 3, resourceType: 'log' },
+    { x: 7, y: 7, resourceType: 'stone' },
+  ];
+  return { world, map };
+}
+
+function createTestNPC(world: World, x: number, y: number, inv?: Map<string, number>) {
+  const e = world.createEntity();
+  world.addComponent<Position>(e, 'position', { x, y });
+  world.addComponent<Needs>(e, 'needs', { hunger: 80, energy: 80, productivity: 20 });
+  world.addComponent<Movement>(e, 'movement', { state: 'idle', target: null, path: [], direction: 0, moveProgress: 0 });
+  world.addComponent<NPCBrain>(e, 'npcBrain', { currentGoal: 'wander', goalQueue: [] });
+  world.addComponent<Map<string, number>>(e, 'inventory', inv ?? new Map());
+  world.addComponent<Stats>(e, 'stats', {
+    strength: 10, dexterity: 10, constitution: 10, intelligence: 10, perception: 10,
+    sociability: 10, courage: 10, curiosity: 10, empathy: 10, temperament: 10,
+  });
+  world.addComponent<StatModifiers>(e, 'statModifiers', { modifiers: [] });
+  return e;
+}
+
+describe('industry integration', () => {
+  it('NPC with materials crafts a tool', () => {
+    const { world, map } = createTestWorld();
+    const inv = new Map([['log', 4], ['stone', 2]]);
+    const e = createTestNPC(world, 5, 5, inv);
+
+    industrySystem(world, map);
+    const brain = world.getComponent<NPCBrain>(e, 'npcBrain')!;
+    expect(brain.currentGoal).toBe('craft');
+
+    const cs = world.getComponent<CraftingState>(e, 'craftingState')!;
+    const ticks = cs.ticksRemaining;
+    for (let i = 0; i < ticks + 1; i++) {
+      craftingSystem(world);
+    }
+
+    const finalInv = world.getComponent<Map<string, number>>(e, 'inventory')!;
+    expect(finalInv.has('wooden_axe') || finalInv.has('hammer')).toBe(true);
+  });
+
+  it('NPC builds a stockpile when it has materials and no stockpile exists', () => {
+    const { world, map } = createTestWorld();
+    const inv = new Map([['log', 4]]);
+    const e = createTestNPC(world, 5, 5, inv);
+
+    industrySystem(world, map);
+    const brain = world.getComponent<NPCBrain>(e, 'npcBrain')!;
+    expect(brain.currentGoal).toBe('build');
+
+    const bs = world.getComponent<BuildingState>(e, 'buildingState')!;
+    for (let i = 0; i < 60; i++) {
+      buildingSystem(world, map);
+    }
+
+    const structure = world.getComponent<StructureData>(bs.structureEntityId, 'structure')!;
+    expect(structure.buildProgress).toBeUndefined();
+  });
+
+  it('NPC drops off items at stockpile after gathering', () => {
+    const { world, map } = createTestWorld();
+    const e = createTestNPC(world, 5, 5, new Map([['log', 2]]));
+
+    const stockpileEntity = world.createEntity();
+    world.addComponent<Position>(stockpileEntity, 'position', { x: 5, y: 5 });
+    world.addComponent<StructureData>(stockpileEntity, 'structure', {
+      type: 'stockpile',
+      subtype: 'general',
+      inventory: new Map(),
+    });
+
+    const brain = world.getComponent<NPCBrain>(e, 'npcBrain')!;
+    brain.currentGoal = 'dropoff';
+
+    dropoffSystem(world, map);
+
+    const npcInv = world.getComponent<Map<string, number>>(e, 'inventory')!;
+    expect(npcInv.size).toBe(0);
+
+    const stockpile = world.getComponent<StructureData>(stockpileEntity, 'structure')!;
+    expect(stockpile.inventory.get('log')).toBe(2);
+    expect(brain.currentGoal).toBe('wander');
+  });
+
+  it('full lifecycle: no materials → gather fallback', () => {
+    const { world, map } = createTestWorld();
+    const e = createTestNPC(world, 5, 5);
+
+    industrySystem(world, map);
+    const brain = world.getComponent<NPCBrain>(e, 'npcBrain')!;
+    expect(brain.currentGoal).toBe('gather');
+  });
+});