feat(finance): support weighted rent split

2026-03-31 12:04:02 +00:00 · 2026-03-10 02:47:58 +04:00
parent 9c4fe5cb52
commit 6a04b9d7f5
25 changed files with 2639 additions and 11 deletions
--- a/apps/bot/src/anonymous-feedback.test.ts
+++ b/apps/bot/src/anonymous-feedback.test.ts
@@ -159,6 +159,7 @@ function createHouseholdConfigurationRepository(): HouseholdConfigurationReposit
      displayName: input.displayName,
      preferredLocale: input.preferredLocale ?? null,
      householdDefaultLocale: 'ru',
+      rentShareWeight: 1,
      isAdmin: input.isAdmin === true
    }),
    getHouseholdMember: async () => null,
@@ -171,6 +172,7 @@ function createHouseholdConfigurationRepository(): HouseholdConfigurationReposit
        displayName: 'Stan',
        preferredLocale: null,
        householdDefaultLocale: 'ru',
+        rentShareWeight: 1,
        isAdmin: false
      }
    ],
@@ -191,6 +193,7 @@ function createHouseholdConfigurationRepository(): HouseholdConfigurationReposit
      displayName: 'Stan',
      preferredLocale: locale,
      householdDefaultLocale: 'ru',
+      rentShareWeight: 1,
      isAdmin: false
    }),
    getHouseholdBillingSettings: async (householdId) => ({
@@ -222,7 +225,8 @@ function createHouseholdConfigurationRepository(): HouseholdConfigurationReposit
      sortOrder: input.sortOrder,
      isActive: input.isActive
    }),
-    promoteHouseholdAdmin: async () => null
+    promoteHouseholdAdmin: async () => null,
+    updateHouseholdMemberRentShareWeight: async () => null
  }
 }

--- a/apps/bot/src/miniapp-auth.test.ts
+++ b/apps/bot/src/miniapp-auth.test.ts
@@ -28,6 +28,7 @@ function onboardingRepository(): HouseholdConfigurationRepository {
      displayName: string
      preferredLocale: 'en' | 'ru' | null
      householdDefaultLocale: 'en' | 'ru'
+      rentShareWeight: number
      isAdmin: boolean
    }
  >()
@@ -97,6 +98,7 @@ function onboardingRepository(): HouseholdConfigurationRepository {
        displayName: input.displayName,
        preferredLocale: input.preferredLocale ?? null,
        householdDefaultLocale: household.defaultLocale,
+        rentShareWeight: 1,
        isAdmin: input.isAdmin === true
      }
      members.set(input.telegramUserId, member)
@@ -122,6 +124,7 @@ function onboardingRepository(): HouseholdConfigurationRepository {
        displayName: pending.displayName,
        preferredLocale: null,
        householdDefaultLocale: household.defaultLocale,
+        rentShareWeight: 1,
        isAdmin: input.isAdmin === true
      }
      members.set(pending.telegramUserId, member)
@@ -141,6 +144,15 @@ function onboardingRepository(): HouseholdConfigurationRepository {
          }
        : null
    },
+    updateHouseholdMemberRentShareWeight: async (_householdId, memberId, rentShareWeight) => {
+      const member = [...members.values()].find((entry) => entry.id === memberId)
+      return member
+        ? {
+            ...member,
+            rentShareWeight
+          }
+        : null
+    },
    getHouseholdBillingSettings: async (householdId) => ({
      householdId,
      rentAmountMinor: null,
--- a/apps/bot/src/miniapp-billing.test.ts
+++ b/apps/bot/src/miniapp-billing.test.ts
@@ -70,6 +70,7 @@ function onboardingRepository(): HouseholdConfigurationRepository {
      displayName: input.displayName,
      preferredLocale: input.preferredLocale ?? null,
      householdDefaultLocale: household.defaultLocale,
+      rentShareWeight: 1,
      isAdmin: input.isAdmin === true
    }),
    getHouseholdMember: async () => null,
@@ -111,6 +112,7 @@ function onboardingRepository(): HouseholdConfigurationRepository {
        displayName: 'Stan',
        preferredLocale: null,
        householdDefaultLocale: 'ru',
+        rentShareWeight: 1,
        isAdmin: true
      }
    ],
@@ -121,7 +123,8 @@ function onboardingRepository(): HouseholdConfigurationRepository {
      defaultLocale: locale
    }),
    updateMemberPreferredLocale: async () => null,
-    promoteHouseholdAdmin: async () => null
+    promoteHouseholdAdmin: async () => null,
+    updateHouseholdMemberRentShareWeight: async () => null
  }
 }

--- a/apps/bot/src/miniapp-dashboard.test.ts
+++ b/apps/bot/src/miniapp-dashboard.test.ts
@@ -24,6 +24,7 @@ function repository(
        id: 'member-1',
        telegramUserId: '123456',
        displayName: 'Stan',
+        rentShareWeight: 1,
        isAdmin: true
      }
    ],
@@ -124,6 +125,7 @@ function onboardingRepository(): HouseholdConfigurationRepository {
      displayName: input.displayName,
      preferredLocale: input.preferredLocale ?? null,
      householdDefaultLocale: household.defaultLocale,
+      rentShareWeight: 1,
      isAdmin: input.isAdmin === true
    }),
    getHouseholdMember: async () => null,
@@ -165,7 +167,8 @@ function onboardingRepository(): HouseholdConfigurationRepository {
      sortOrder: input.sortOrder,
      isActive: input.isActive
    }),
-    promoteHouseholdAdmin: async () => null
+    promoteHouseholdAdmin: async () => null,
+    updateHouseholdMemberRentShareWeight: async () => null
  }
 }

@@ -177,6 +180,7 @@ describe('createMiniAppDashboardHandler', () => {
        id: 'member-1',
        telegramUserId: '123456',
        displayName: 'Stan',
+        rentShareWeight: 1,
        isAdmin: true
      })
    )
@@ -189,6 +193,7 @@ describe('createMiniAppDashboardHandler', () => {
        displayName: 'Stan',
        preferredLocale: null,
        householdDefaultLocale: 'ru',
+        rentShareWeight: 1,
        isAdmin: true
      }
    ]
@@ -255,6 +260,7 @@ describe('createMiniAppDashboardHandler', () => {
        id: 'member-1',
        telegramUserId: '123456',
        displayName: 'Stan',
+        rentShareWeight: 1,
        isAdmin: true
      })
    )
@@ -267,6 +273,7 @@ describe('createMiniAppDashboardHandler', () => {
        displayName: 'Stan',
        preferredLocale: null,
        householdDefaultLocale: 'ru',
+        rentShareWeight: 1,
        isAdmin: true
      }
    ]
--- a/apps/bot/src/miniapp-locale.test.ts
+++ b/apps/bot/src/miniapp-locale.test.ts
@@ -33,6 +33,7 @@ function repository(): HouseholdConfigurationRepository {
        displayName: 'Stan',
        preferredLocale: null,
        householdDefaultLocale: household.defaultLocale,
+        rentShareWeight: 1,
        isAdmin: true
      }
    ],
@@ -45,6 +46,7 @@ function repository(): HouseholdConfigurationRepository {
        displayName: 'Mia',
        preferredLocale: null,
        householdDefaultLocale: household.defaultLocale,
+        rentShareWeight: 1,
        isAdmin: false
      }
    ]
@@ -92,6 +94,7 @@ function repository(): HouseholdConfigurationRepository {
        displayName: input.displayName,
        preferredLocale: input.preferredLocale ?? null,
        householdDefaultLocale: household.defaultLocale,
+        rentShareWeight: 1,
        isAdmin: input.isAdmin === true
      },
    getHouseholdMember: async (_householdId, telegramUserId) => members.get(telegramUserId) ?? null,
@@ -154,7 +157,8 @@ function repository(): HouseholdConfigurationRepository {
      sortOrder: input.sortOrder,
      isActive: input.isActive
    }),
-    promoteHouseholdAdmin: async () => null
+    promoteHouseholdAdmin: async () => null,
+    updateHouseholdMemberRentShareWeight: async () => null
  }
 }

--- a/docs/specs/HOUSEBOT-077-custom-rent-split-weights.md
+++ b/docs/specs/HOUSEBOT-077-custom-rent-split-weights.md
@@ -0,0 +1,48 @@
+# HOUSEBOT-077 Custom Rent Split Weights
+
+## Summary
+
+Support unequal room rents by storing a deterministic rent-share weight per active household member and using those weights in monthly settlement calculations.
+
+## Goals
+
+- Preserve equal split as the default when all member weights are `1`.
+- Allow household admins to edit per-member rent weights from the mini app.
+- Keep settlement math deterministic and money-safe.
+- Reflect weighted rent shares consistently in statements and dashboard views.
+
+## Non-goals
+
+- Per-cycle rent weights.
+- Free-form percentage editing.
+- Automatic square-meter or room-type calculations.
+
+## Scope
+
+- In: member-level `rentShareWeight`, settlement-engine support, admin API/UI, tests.
+- Out: historical backfill UI, move-in/move-out proration logic, rent history analytics.
+
+## Data Model Changes
+
+- Add `members.rent_share_weight integer not null default 1`.
+- Existing members migrate to `1`.
+
+## Domain Rules
+
+- Rent weights must be positive integers.
+- Active members participate in rent splitting according to their weight.
+- Utility splitting remains independent from rent splitting.
+- The same input must always produce the same minor-unit allocation.
+
+## Interfaces
+
+- Household admin mini app payload includes member `rentShareWeight`.
+- Admin write endpoint updates one member rent weight at a time.
+
+## Acceptance Criteria
+
+- [ ] Settlement engine uses weighted rent shares.
+- [ ] Equal split still holds when all weights are `1`.
+- [ ] Admins can edit member rent weights in the mini app.
+- [ ] Dashboard and statements reflect the new rent shares.
+- [ ] Validation rejects zero or negative weights.
--- a/packages/adapters-db/src/finance-repository.ts
+++ b/packages/adapters-db/src/finance-repository.ts
@@ -38,6 +38,7 @@ export function createDbFinanceRepository(
          id: schema.members.id,
          telegramUserId: schema.members.telegramUserId,
          displayName: schema.members.displayName,
+          rentShareWeight: schema.members.rentShareWeight,
          isAdmin: schema.members.isAdmin
        })
        .from(schema.members)
@@ -66,6 +67,7 @@ export function createDbFinanceRepository(
          id: schema.members.id,
          telegramUserId: schema.members.telegramUserId,
          displayName: schema.members.displayName,
+          rentShareWeight: schema.members.rentShareWeight,
          isAdmin: schema.members.isAdmin
        })
        .from(schema.members)
--- a/packages/adapters-db/src/household-config-repository.ts
+++ b/packages/adapters-db/src/household-config-repository.ts
@@ -115,6 +115,7 @@ function toHouseholdMemberRecord(row: {
  displayName: string
  preferredLocale: string | null
  defaultLocale: string
+  rentShareWeight: number
  isAdmin: number
 }): HouseholdMemberRecord {
  const householdDefaultLocale = normalizeSupportedLocale(row.defaultLocale)
@@ -129,6 +130,7 @@ function toHouseholdMemberRecord(row: {
    displayName: row.displayName,
    preferredLocale: normalizeSupportedLocale(row.preferredLocale),
    householdDefaultLocale,
+    rentShareWeight: row.rentShareWeight,
    isAdmin: row.isAdmin === 1
  }
 }
@@ -766,6 +768,7 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
          telegramUserId: input.telegramUserId,
          displayName: input.displayName,
          preferredLocale: input.preferredLocale ?? null,
+          rentShareWeight: input.rentShareWeight ?? 1,
          isAdmin: input.isAdmin ? 1 : 0
        })
        .onConflictDoUpdate({
@@ -773,6 +776,7 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
          set: {
            displayName: input.displayName,
            preferredLocale: input.preferredLocale ?? schema.members.preferredLocale,
+            rentShareWeight: input.rentShareWeight ?? schema.members.rentShareWeight,
            ...(input.isAdmin
              ? {
                  isAdmin: 1
@@ -786,6 +790,7 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
          telegramUserId: schema.members.telegramUserId,
          displayName: schema.members.displayName,
          preferredLocale: schema.members.preferredLocale,
+          rentShareWeight: schema.members.rentShareWeight,
          isAdmin: schema.members.isAdmin
        })

@@ -813,6 +818,7 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
          telegramUserId: schema.members.telegramUserId,
          displayName: schema.members.displayName,
          preferredLocale: schema.members.preferredLocale,
+          rentShareWeight: schema.members.rentShareWeight,
          defaultLocale: schema.households.defaultLocale,
          isAdmin: schema.members.isAdmin
        })
@@ -838,6 +844,7 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
          telegramUserId: schema.members.telegramUserId,
          displayName: schema.members.displayName,
          preferredLocale: schema.members.preferredLocale,
+          rentShareWeight: schema.members.rentShareWeight,
          defaultLocale: schema.households.defaultLocale,
          isAdmin: schema.members.isAdmin
        })
@@ -1012,6 +1019,7 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
          telegramUserId: schema.members.telegramUserId,
          displayName: schema.members.displayName,
          preferredLocale: schema.members.preferredLocale,
+          rentShareWeight: schema.members.rentShareWeight,
          defaultLocale: schema.households.defaultLocale,
          isAdmin: schema.members.isAdmin
        })
@@ -1082,6 +1090,7 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
            telegramUserId: pending.telegramUserId,
            displayName: pending.displayName,
            preferredLocale: normalizeSupportedLocale(pending.languageCode),
+            rentShareWeight: 1,
            isAdmin: input.isAdmin ? 1 : 0
          })
          .onConflictDoUpdate({
@@ -1103,6 +1112,7 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
            telegramUserId: schema.members.telegramUserId,
            displayName: schema.members.displayName,
            preferredLocale: schema.members.preferredLocale,
+            rentShareWeight: schema.members.rentShareWeight,
            isAdmin: schema.members.isAdmin
          })

@@ -1174,6 +1184,7 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
          telegramUserId: schema.members.telegramUserId,
          displayName: schema.members.displayName,
          preferredLocale: schema.members.preferredLocale,
+          rentShareWeight: schema.members.rentShareWeight,
          isAdmin: schema.members.isAdmin
        })

@@ -1206,6 +1217,7 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
          telegramUserId: schema.members.telegramUserId,
          displayName: schema.members.displayName,
          preferredLocale: schema.members.preferredLocale,
+          rentShareWeight: schema.members.rentShareWeight,
          isAdmin: schema.members.isAdmin
        })

@@ -1219,6 +1231,39 @@ export function createDbHouseholdConfigurationRepository(databaseUrl: string): {
        throw new Error('Failed to resolve household chat after admin promotion')
      }

+      return toHouseholdMemberRecord({
+        ...row,
+        defaultLocale: household.defaultLocale
+      })
+    },
+
+    async updateHouseholdMemberRentShareWeight(householdId, memberId, rentShareWeight) {
+      const rows = await db
+        .update(schema.members)
+        .set({
+          rentShareWeight
+        })
+        .where(and(eq(schema.members.householdId, householdId), eq(schema.members.id, memberId)))
+        .returning({
+          id: schema.members.id,
+          householdId: schema.members.householdId,
+          telegramUserId: schema.members.telegramUserId,
+          displayName: schema.members.displayName,
+          preferredLocale: schema.members.preferredLocale,
+          rentShareWeight: schema.members.rentShareWeight,
+          isAdmin: schema.members.isAdmin
+        })
+
+      const row = rows[0]
+      if (!row) {
+        return null
+      }
+
+      const household = await this.getHouseholdChatByHouseholdId(householdId)
+      if (!household) {
+        throw new Error('Failed to resolve household chat after rent weight update')
+      }
+
      return toHouseholdMemberRecord({
        ...row,
        defaultLocale: household.defaultLocale
--- a/packages/application/src/finance-command-service.test.ts
+++ b/packages/application/src/finance-command-service.test.ts
@@ -216,12 +216,14 @@ describe('createFinanceCommandService', () => {
        id: 'alice',
        telegramUserId: '100',
        displayName: 'Alice',
+        rentShareWeight: 1,
        isAdmin: true
      },
      {
        id: 'bob',
        telegramUserId: '200',
        displayName: 'Bob',
+        rentShareWeight: 1,
        isAdmin: false
      }
    ]
--- a/packages/application/src/finance-command-service.ts
+++ b/packages/application/src/finance-command-service.ts
@@ -130,7 +130,8 @@ async function buildFinanceDashboard(
    utilitySplitMode: 'equal',
    members: members.map((member) => ({
      memberId: MemberId.from(member.id),
-      active: true
+      active: true,
+      rentWeight: member.rentShareWeight
    })),
    purchases: purchases.map((purchase) => ({
      purchaseId: PurchaseEntryId.from(purchase.id),
--- a/packages/application/src/household-admin-service.test.ts
+++ b/packages/application/src/household-admin-service.test.ts
@@ -30,6 +30,7 @@ function createRepositoryStub() {
    displayName: 'Stan',
    preferredLocale: null,
    householdDefaultLocale: household.defaultLocale,
+    rentShareWeight: 1,
    isAdmin: true
  })
  pendingMembers.set('2', {
@@ -94,6 +95,7 @@ function createRepositoryStub() {
        displayName: input.displayName,
        preferredLocale: input.preferredLocale ?? null,
        householdDefaultLocale: household.defaultLocale,
+        rentShareWeight: 1,
        isAdmin: input.isAdmin === true
      }
      members.set(input.telegramUserId, record)
@@ -120,6 +122,7 @@ function createRepositoryStub() {
        displayName: pending.displayName,
        preferredLocale: null,
        householdDefaultLocale: household.defaultLocale,
+        rentShareWeight: 1,
        isAdmin: input.isAdmin === true
      }
      members.set(member.telegramUserId, member)
@@ -167,7 +170,8 @@ function createRepositoryStub() {
      sortOrder: input.sortOrder,
      isActive: input.isActive
    }),
-    promoteHouseholdAdmin: async () => null
+    promoteHouseholdAdmin: async () => null,
+    updateHouseholdMemberRentShareWeight: async () => null
  }

  return {
@@ -238,6 +242,7 @@ describe('createHouseholdAdminService', () => {
        displayName: 'Alice',
        preferredLocale: null,
        householdDefaultLocale: 'ru',
+        rentShareWeight: 1,
        isAdmin: false
      }
    })
--- a/packages/application/src/household-onboarding-service.test.ts
+++ b/packages/application/src/household-onboarding-service.test.ts
@@ -100,6 +100,7 @@ function createRepositoryStub() {
        displayName: input.displayName,
        preferredLocale: input.preferredLocale ?? null,
        householdDefaultLocale: household.defaultLocale,
+        rentShareWeight: 1,
        isAdmin: input.isAdmin === true
      }
      members.set(input.telegramUserId, member)
@@ -133,6 +134,7 @@ function createRepositoryStub() {
        displayName: pending.displayName,
        preferredLocale: null,
        householdDefaultLocale: household.defaultLocale,
+        rentShareWeight: 1,
        isAdmin: input.isAdmin === true
      }
    },
@@ -190,6 +192,9 @@ function createRepositoryStub() {
    },
    async promoteHouseholdAdmin() {
      return null
+    },
+    async updateHouseholdMemberRentShareWeight() {
+      return null
    }
  }

@@ -319,6 +324,7 @@ describe('createHouseholdOnboardingService', () => {
        displayName: 'Stan',
        preferredLocale: null,
        householdDefaultLocale: 'ru',
+        rentShareWeight: 1,
        isAdmin: true
      }
    })
@@ -333,13 +339,14 @@ describe('createHouseholdOnboardingService', () => {
      displayName: 'Stan',
      preferredLocale: null,
      householdDefaultLocale: 'ru',
+      rentShareWeight: 1,
      isAdmin: true
    }
    const service = createHouseholdOnboardingService({ repository })
    const duplicateRepository = repository as HouseholdConfigurationRepository & {
      listHouseholdMembersByTelegramUserId: (
        telegramUserId: string
-      ) => Promise<readonly HouseholdMemberRecord[]>
+      ) => Promise<readonly (HouseholdMemberRecord & { rentShareWeight: number })[]>
    }
    duplicateRepository.listHouseholdMembersByTelegramUserId = async () => [
      member,
@@ -350,6 +357,7 @@ describe('createHouseholdOnboardingService', () => {
        displayName: 'Stan elsewhere',
        preferredLocale: null,
        householdDefaultLocale: 'ru',
+        rentShareWeight: 1,
        isAdmin: false
      }
    ]
--- a/packages/application/src/household-onboarding-service.ts
+++ b/packages/application/src/household-onboarding-service.ts
@@ -20,6 +20,7 @@ export type HouseholdMiniAppAccess =
        isAdmin: boolean
        preferredLocale: SupportedLocale | null
        householdDefaultLocale: SupportedLocale
+        rentShareWeight: number
      }
    }
  | {
@@ -70,6 +71,7 @@ export interface HouseholdOnboardingService {
          isAdmin: boolean
          preferredLocale: SupportedLocale | null
          householdDefaultLocale: SupportedLocale
+          rentShareWeight: number
        }
      }
    | {
@@ -85,6 +87,7 @@ function toMember(member: HouseholdMemberRecord): {
  isAdmin: boolean
  preferredLocale: SupportedLocale | null
  householdDefaultLocale: SupportedLocale
+  rentShareWeight: number
 } {
  return {
    id: member.id,
@@ -92,7 +95,8 @@ function toMember(member: HouseholdMemberRecord): {
    displayName: member.displayName,
    isAdmin: member.isAdmin,
    preferredLocale: member.preferredLocale,
-    householdDefaultLocale: member.householdDefaultLocale
+    householdDefaultLocale: member.householdDefaultLocale,
+    rentShareWeight: member.rentShareWeight
  }
 }

--- a/packages/application/src/household-setup-service.test.ts
+++ b/packages/application/src/household-setup-service.test.ts
@@ -175,6 +175,7 @@ function createRepositoryStub() {
        householdDefaultLocale:
          [...households.values()].find((household) => household.householdId === input.householdId)
            ?.defaultLocale ?? 'ru',
+        rentShareWeight: input.rentShareWeight ?? existing?.rentShareWeight ?? 1,
        isAdmin: input.isAdmin === true || existing?.isAdmin === true
      }
      members.set(key, next)
@@ -216,6 +217,7 @@ function createRepositoryStub() {
          [...households.values()].find(
            (household) => household.householdId === pending.householdId
          )?.defaultLocale ?? 'ru',
+        rentShareWeight: 1,
        isAdmin: input.isAdmin === true
      }
      members.set(key, member)
@@ -296,6 +298,22 @@ function createRepositoryStub() {
      }
      members.set(`${householdId}:${member.telegramUserId}`, next)
      return next
+    },
+
+    async updateHouseholdMemberRentShareWeight(householdId, memberId, rentShareWeight) {
+      const member = [...members.values()].find(
+        (entry) => entry.householdId === householdId && entry.id === memberId
+      )
+      if (!member) {
+        return null
+      }
+
+      const next = {
+        ...member,
+        rentShareWeight
+      }
+      members.set(`${householdId}:${member.telegramUserId}`, next)
+      return next
    }
  }

@@ -332,6 +350,7 @@ describe('createHouseholdSetupService', () => {
      displayName: 'Stan',
      preferredLocale: null,
      householdDefaultLocale: 'ru',
+      rentShareWeight: 1,
      isAdmin: true
    })
  })
@@ -369,6 +388,7 @@ describe('createHouseholdSetupService', () => {
      displayName: 'Mia',
      preferredLocale: null,
      householdDefaultLocale: 'ru',
+      rentShareWeight: 1,
      isAdmin: true
    })
  })
--- a/packages/application/src/locale-preference-service.test.ts
+++ b/packages/application/src/locale-preference-service.test.ts
@@ -21,6 +21,7 @@ function createRepository(): HouseholdConfigurationRepository {
    displayName: 'Stan',
    preferredLocale: null,
    householdDefaultLocale: 'ru',
+    rentShareWeight: 1,
    isAdmin: true
  }

@@ -104,7 +105,8 @@ function createRepository(): HouseholdConfigurationRepository {
      sortOrder: input.sortOrder,
      isActive: input.isActive
    }),
-    promoteHouseholdAdmin: async () => null
+    promoteHouseholdAdmin: async () => null,
+    updateHouseholdMemberRentShareWeight: async () => null
  }
 }

--- a/packages/application/src/settlement-engine.test.ts
+++ b/packages/application/src/settlement-engine.test.ts
@@ -83,6 +83,25 @@ describe('calculateMonthlySettlement', () => {
    expect(result.totalDue.amountMinor).toBe(82000n)
  })

+  test('supports weighted rent split by member weights', () => {
+    const input = {
+      ...fixtureBase(),
+      utilitySplitMode: 'equal' as const,
+      members: [
+        { memberId: MemberId.from('a'), active: true, rentWeight: 3 },
+        { memberId: MemberId.from('b'), active: true, rentWeight: 2 },
+        { memberId: MemberId.from('c'), active: true, rentWeight: 1 }
+      ],
+      purchases: []
+    }
+
+    const result = calculateMonthlySettlement(input)
+
+    expect(result.lines.map((line) => line.rentShare.amountMinor)).toEqual([35000n, 23333n, 11667n])
+    expect(result.lines.map((line) => line.utilityShare.amountMinor)).toEqual([4000n, 4000n, 4000n])
+    expect(result.totalDue.amountMinor).toBe(82000n)
+  })
+
  test('5-member scenario with two purchases remains deterministic', () => {
    const input = {
      ...fixtureBase(),
@@ -150,4 +169,18 @@ describe('calculateMonthlySettlement', () => {

    expect(() => calculateMonthlySettlement(input)).toThrow(DomainError)
  })
+
+  test('throws if rent split is selected with invalid rent weights', () => {
+    const input = {
+      ...fixtureBase(),
+      utilitySplitMode: 'equal' as const,
+      members: [
+        { memberId: MemberId.from('a'), active: true, rentWeight: 1 },
+        { memberId: MemberId.from('b'), active: true, rentWeight: 0 }
+      ],
+      purchases: []
+    }
+
+    expect(() => calculateMonthlySettlement(input)).toThrow(DomainError)
+  })
 })
--- a/packages/application/src/settlement-engine.ts
+++ b/packages/application/src/settlement-engine.ts
@@ -82,6 +82,31 @@ function validateWeightedUtilityDays(members: readonly SettlementMemberInput[]):
  return weights
 }

+function validateRentWeights(members: readonly SettlementMemberInput[]): readonly bigint[] {
+  const weights = members.map((member) => {
+    const raw = member.rentWeight ?? 1
+
+    if (!Number.isInteger(raw) || raw <= 0) {
+      throw new DomainError(
+        DOMAIN_ERROR_CODE.INVALID_SETTLEMENT_INPUT,
+        `rentWeight must be a positive integer for member ${member.memberId.toString()}`
+      )
+    }
+
+    return BigInt(raw)
+  })
+
+  const total = weights.reduce((sum, current) => sum + current, 0n)
+  if (total <= 0n) {
+    throw new DomainError(
+      DOMAIN_ERROR_CODE.INVALID_SETTLEMENT_INPUT,
+      'Total rent weights must be positive'
+    )
+  }
+
+  return weights
+}
+
 function validateCurrencyConsistency(input: SettlementInput): void {
  const currency = input.rent.currency

@@ -114,7 +139,7 @@ export function calculateMonthlySettlement(input: SettlementInput): SettlementRe
    activeMembers.map((member) => [member.memberId.toString(), createMemberState(member, currency)])
  )

-  const rentShares = input.rent.splitEvenly(activeMembers.length)
+  const rentShares = input.rent.splitByWeights(validateRentWeights(activeMembers))
  for (const [index, member] of activeMembers.entries()) {
    const state = membersById.get(member.memberId.toString())
    if (!state) {
--- a/packages/db/drizzle-checksums.json
+++ b/packages/db/drizzle-checksums.json
@@ -10,6 +10,8 @@
    "0006_marvelous_nehzno.sql": "369a862f68dede5568116e29865aa3c8a7a0ff494487af1b202b62932ffe83f4",
    "0007_sudden_murmur.sql": "eedf265c46705c20be4ddb3e2bd7d9670108756915b911e580e19a00f8118104",
    "0008_lowly_spiral.sql": "4f016332d60f7ef1fef0311210a0fa1a0bfc1d9b6da1da4380a60c14d54a9681",
-    "0009_quiet_wallflower.sql": "c5bcb6a01b6f22a9e64866ac0d11468105aad8b2afb248296370f15b462e3087"
+    "0009_quiet_wallflower.sql": "c5bcb6a01b6f22a9e64866ac0d11468105aad8b2afb248296370f15b462e3087",
+    "0010_wild_molecule_man.sql": "46027a6ac770cdc2efd4c3eb5bb53f09d1b852c70fdc46a2434e5a7064587245",
+    "0011_previous_ezekiel_stane.sql": "d996e64d3854de22e36dedeaa94e46774399163d90263bbb05e0b9199af79b70"
  }
 }
--- a/packages/db/drizzle/0011_previous_ezekiel_stane.sql
+++ b/packages/db/drizzle/0011_previous_ezekiel_stane.sql
@@ -0,0 +1 @@
+ALTER TABLE "members" ADD COLUMN "rent_share_weight" integer DEFAULT 1 NOT NULL;
--- a/packages/db/drizzle/meta/0011_snapshot.json
+++ b/packages/db/drizzle/meta/0011_snapshot.json
--- a/packages/db/drizzle/meta/_journal.json
+++ b/packages/db/drizzle/meta/_journal.json
@@ -78,6 +78,13 @@
      "when": 1773092080214,
      "tag": "0010_wild_molecule_man",
      "breakpoints": true
+    },
+    {
+      "idx": 11,
+      "version": "7",
+      "when": 1773096404367,
+      "tag": "0011_previous_ezekiel_stane",
+      "breakpoints": true
    }
  ]
 }
--- a/packages/db/src/schema.ts
+++ b/packages/db/src/schema.ts
@@ -194,6 +194,7 @@ export const members = pgTable(
    telegramUserId: text('telegram_user_id').notNull(),
    displayName: text('display_name').notNull(),
    preferredLocale: text('preferred_locale'),
+    rentShareWeight: integer('rent_share_weight').default(1).notNull(),
    isAdmin: integer('is_admin').default(0).notNull(),
    joinedAt: timestamp('joined_at', { withTimezone: true }).defaultNow().notNull()
  },
--- a/packages/domain/src/settlement-primitives.ts
+++ b/packages/domain/src/settlement-primitives.ts
@@ -7,6 +7,7 @@ export type UtilitySplitMode = 'equal' | 'weighted_by_days'
 export interface SettlementMemberInput {
  memberId: MemberId
  active: boolean
+  rentWeight?: number
  utilityDays?: number
 }

--- a/packages/ports/src/finance.ts
+++ b/packages/ports/src/finance.ts
@@ -4,6 +4,7 @@ export interface FinanceMemberRecord {
  id: string
  telegramUserId: string
  displayName: string
+  rentShareWeight: number
  isAdmin: boolean
 }

--- a/packages/ports/src/household-config.ts
+++ b/packages/ports/src/household-config.ts
@@ -45,6 +45,7 @@ export interface HouseholdMemberRecord {
  displayName: string
  preferredLocale: SupportedLocale | null
  householdDefaultLocale: SupportedLocale
+  rentShareWeight: number
  isAdmin: boolean
 }

@@ -128,6 +129,7 @@ export interface HouseholdConfigurationRepository {
    telegramUserId: string
    displayName: string
    preferredLocale?: SupportedLocale | null
+    rentShareWeight?: number
    isAdmin?: boolean
  }): Promise<HouseholdMemberRecord>
  getHouseholdMember(
@@ -178,4 +180,9 @@ export interface HouseholdConfigurationRepository {
    householdId: string,
    memberId: string
  ): Promise<HouseholdMemberRecord | null>
+  updateHouseholdMemberRentShareWeight(
+    householdId: string,
+    memberId: string,
+    rentShareWeight: number
+  ): Promise<HouseholdMemberRecord | null>
 }
				`@@ -0,0 +1 @@`
				`ALTER TABLE "members" ADD COLUMN "rent_share_weight" integer DEFAULT 1 NOT NULL;`