Loans2: Bets return you some capital every week (#588)

* Remove some old loan code

* Almost complete implementation of updateLoans cloud function

* Merge fixes

* Use invested instead of sale value, check if eligible, perform payouts

* Run monday 12am

* Implement loan income notification

* Fix imports

* Loan update fixes / debug

* Handle NaN and negative loan calcs

* Working loan notification

* Loan modal!

* Move loans calculation to /common

* Better layout

* Pay back loan on sell shares

* Pay back fraction of loan on redeem

* Sell bet loan: negate buy bet's loan

* Modal tweaks

* Compute and store nextLoanCached for all users

* lint

* Update loans with newest portfolio

* Filter loans to only unresolved contracts

* Tweak spacing

* Increase memory

common/bet.ts

@@ -61,5 +61,3 @@ export type fill = {
   // I.e. -fill.shares === matchedBet.shares
   isSale?: boolean
 }
-
-export const MAX_LOAN_PER_CONTRACT = 20

common/loans.ts

@@ -0,0 +1,138 @@
+import { Dictionary, groupBy, sumBy, minBy } from 'lodash'
+import { Bet } from './bet'
+import { getContractBetMetrics } from './calculate'
+import {
+  Contract,
+  CPMMContract,
+  FreeResponseContract,
+  MultipleChoiceContract,
+} from './contract'
+import { PortfolioMetrics, User } from './user'
+import { filterDefined } from './util/array'
+
+const LOAN_WEEKLY_RATE = 0.05
+
+const calculateNewLoan = (investedValue: number, loanTotal: number) => {
+  const netValue = investedValue - loanTotal
+  return netValue * LOAN_WEEKLY_RATE
+}
+
+export const getLoanUpdates = (
+  users: User[],
+  contractsById: { [contractId: string]: Contract },
+  portfolioByUser: { [userId: string]: PortfolioMetrics | undefined },
+  betsByUser: { [userId: string]: Bet[] }
+) => {
+  const eligibleUsers = filterDefined(
+    users.map((user) =>
+      isUserEligibleForLoan(portfolioByUser[user.id]) ? user : undefined
+    )
+  )
+
+  const betUpdates = eligibleUsers
+    .map((user) => {
+      const updates = calculateLoanBetUpdates(
+        betsByUser[user.id] ?? [],
+        contractsById
+      ).betUpdates
+      return updates.map((update) => ({ ...update, user }))
+    })
+    .flat()
+
+  const updatesByUser = groupBy(betUpdates, (update) => update.userId)
+  const userPayouts = Object.values(updatesByUser).map((updates) => {
+    return {
+      user: updates[0].user,
+      payout: sumBy(updates, (update) => update.newLoan),
+    }
+  })
+
+  return {
+    betUpdates,
+    userPayouts,
+  }
+}
+
+const isUserEligibleForLoan = (portfolio: PortfolioMetrics | undefined) => {
+  if (!portfolio) return true
+
+  const { balance, investmentValue } = portfolio
+  return balance + investmentValue > 0
+}
+
+const calculateLoanBetUpdates = (
+  bets: Bet[],
+  contractsById: Dictionary<Contract>
+) => {
+  const betsByContract = groupBy(bets, (bet) => bet.contractId)
+  const contracts = filterDefined(
+    Object.keys(betsByContract).map((contractId) => contractsById[contractId])
+  ).filter((c) => !c.isResolved)
+
+  const betUpdates = filterDefined(
+    contracts
+      .map((c) => {
+        if (c.mechanism === 'cpmm-1') {
+          return getBinaryContractLoanUpdate(c, betsByContract[c.id])
+        } else if (
+          c.outcomeType === 'FREE_RESPONSE' ||
+          c.outcomeType === 'MULTIPLE_CHOICE'
+        )
+          return getFreeResponseContractLoanUpdate(c, betsByContract[c.id])
+        else {
+          // Unsupported contract / mechanism for loans.
+          return []
+        }
+      })
+      .flat()
+  )
+
+  const totalNewLoan = sumBy(betUpdates, (loanUpdate) => loanUpdate.loanTotal)
+
+  return {
+    totalNewLoan,
+    betUpdates,
+  }
+}
+
+const getBinaryContractLoanUpdate = (contract: CPMMContract, bets: Bet[]) => {
+  const { invested } = getContractBetMetrics(contract, bets)
+  const loanAmount = sumBy(bets, (bet) => bet.loanAmount ?? 0)
+  const oldestBet = minBy(bets, (bet) => bet.createdTime)
+
+  const newLoan = calculateNewLoan(invested, loanAmount)
+  if (isNaN(newLoan) || newLoan <= 0 || !oldestBet) return undefined
+
+  const loanTotal = (oldestBet.loanAmount ?? 0) + newLoan
+
+  return {
+    userId: oldestBet.userId,
+    contractId: contract.id,
+    betId: oldestBet.id,
+    newLoan,
+    loanTotal,
+  }
+}
+
+const getFreeResponseContractLoanUpdate = (
+  contract: FreeResponseContract | MultipleChoiceContract,
+  bets: Bet[]
+) => {
+  const openBets = bets.filter((bet) => bet.isSold || bet.sale)
+
+  return openBets.map((bet) => {
+    const loanAmount = bet.loanAmount ?? 0
+    const newLoan = calculateNewLoan(bet.amount, loanAmount)
+    const loanTotal = loanAmount + newLoan
+
+    if (isNaN(newLoan) || newLoan <= 0) return undefined
+
+    return {
+      userId: bet.userId,
+      contractId: contract.id,
+      betId: bet.id,
+      newLoan,
+      loanTotal,
+    }
+  })
+}

common/new-bet.ts

@@ -1,6 +1,6 @@
 import { sortBy, sum, sumBy } from 'lodash'
 
-import { Bet, fill, LimitBet, MAX_LOAN_PER_CONTRACT, NumericBet } from './bet'
+import { Bet, fill, LimitBet, NumericBet } from './bet'
 import {
   calculateDpmShares,
   getDpmProbability,
@@ -276,8 +276,7 @@ export const getBinaryBetStats = (
 export const getNewBinaryDpmBetInfo = (
   outcome: 'YES' | 'NO',
   amount: number,
-  contract: DPMBinaryContract,
-  loanAmount: number
+  contract: DPMBinaryContract
 ) => {
   const { YES: yesPool, NO: noPool } = contract.pool
 
@@ -308,7 +307,7 @@ export const getNewBinaryDpmBetInfo = (
   const newBet: CandidateBet = {
     contractId: contract.id,
     amount,
-    loanAmount,
+    loanAmount: 0,
     shares,
     outcome,
     probBefore,
@@ -324,7 +323,6 @@ export const getNewMultiBetInfo = (
   outcome: string,
   amount: number,
   contract: FreeResponseContract | MultipleChoiceContract,
-  loanAmount: number
 ) => {
   const { pool, totalShares, totalBets } = contract
 
@@ -345,7 +343,7 @@ export const getNewMultiBetInfo = (
   const newBet: CandidateBet = {
     contractId: contract.id,
     amount,
-    loanAmount,
+    loanAmount: 0,
     shares,
     outcome,
     probBefore,
@@ -399,13 +397,3 @@ export const getNumericBetsInfo = (
 
   return { newBet, newPool, newTotalShares, newTotalBets }
 }
-
-export const getLoanAmount = (yourBets: Bet[], newBetAmount: number) => {
-  const openBets = yourBets.filter((bet) => !bet.isSold && !bet.sale)
-  const prevLoanAmount = sumBy(openBets, (bet) => bet.loanAmount ?? 0)
-  const loanAmount = Math.min(
-    newBetAmount,
-    MAX_LOAN_PER_CONTRACT - prevLoanAmount
-  )
-  return loanAmount
-}

common/notification.ts

@@ -39,6 +39,7 @@ export type notification_source_types =
   | 'bonus'
   | 'challenge'
   | 'betting_streak_bonus'
+  | 'loan'
 
 export type notification_source_update_types =
   | 'created'
@@ -68,3 +69,4 @@ export type notification_reason_types =
   | 'user_joined_from_your_group_invite'
   | 'challenge_accepted'
   | 'betting_streak_incremented'
+  | 'loan_income'

common/redeem.ts

@@ -13,8 +13,9 @@ export const getRedeemableAmount = (bets: RedeemableBet[]) => {
   const yesShares = sumBy(yesBets, (b) => b.shares)
   const noShares = sumBy(noBets, (b) => b.shares)
   const shares = Math.max(Math.min(yesShares, noShares), 0)
+  const soldFrac = shares > 0 ? Math.min(yesShares, noShares) / shares : 0
   const loanAmount = sumBy(bets, (bet) => bet.loanAmount ?? 0)
-  const loanPayment = Math.min(loanAmount, shares)
+  const loanPayment = loanAmount * soldFrac
   const netAmount = shares - loanPayment
   return { shares, loanPayment, netAmount }
 }

common/sell-bet.ts

@@ -13,7 +13,7 @@ export type CandidateBet<T extends Bet> = Omit<T, 'id' | 'userId'>
 
 export const getSellBetInfo = (bet: Bet, contract: DPMContract) => {
   const { pool, totalShares, totalBets } = contract
-  const { id: betId, amount, shares, outcome } = bet
+  const { id: betId, amount, shares, outcome, loanAmount } = bet
 
   const adjShareValue = calculateDpmShareValue(contract, bet)
 
@@ -64,6 +64,7 @@ export const getSellBetInfo = (bet: Bet, contract: DPMContract) => {
       betId,
     },
     fees,
+    loanAmount: -(loanAmount ?? 0),
   }
 
   return {
@@ -79,8 +80,8 @@ export const getCpmmSellBetInfo = (
   shares: number,
   outcome: 'YES' | 'NO',
   contract: CPMMContract,
-  prevLoanAmount: number,
-  unfilledBets: LimitBet[]
+  unfilledBets: LimitBet[],
+  loanPaid: number
 ) => {
   const { pool, p } = contract
 
@@ -91,7 +92,6 @@ export const getCpmmSellBetInfo = (
     unfilledBets
   )
 
-  const loanPaid = Math.min(prevLoanAmount, saleValue)
   const probBefore = getCpmmProbability(pool, p)
   const probAfter = getCpmmProbability(cpmmState.pool, cpmmState.p)
 

common/user.ts

@@ -32,6 +32,7 @@ export type User = {
     allTime: number
   }
 
+  nextLoanCached: number
   followerCountCached: number
 
   followedCategories?: string[]

functions/src/create-answer.ts

@@ -75,10 +75,8 @@ export const createanswer = newEndpoint(opts, async (req, auth) => {
     }
     transaction.create(newAnswerDoc, answer)
 
-    const loanAmount = 0
-
     const { newBet, newPool, newTotalShares, newTotalBets } =
-      getNewMultiBetInfo(answerId, amount, contract, loanAmount)
+      getNewMultiBetInfo(answerId, amount, contract)
 
     const newBalance = user.balance - amount
     const betDoc = firestore.collection(`contracts/${contractId}/bets`).doc()

functions/src/create-notification.ts

@@ -471,6 +471,32 @@ export const createReferralNotification = async (
   await notificationRef.set(removeUndefinedProps(notification))
 }
 
+export const createLoanIncomeNotification = async (
+  toUser: User,
+  idempotencyKey: string,
+  income: number
+) => {
+  const notificationRef = firestore
+    .collection(`/users/${toUser.id}/notifications`)
+    .doc(idempotencyKey)
+  const notification: Notification = {
+    id: idempotencyKey,
+    userId: toUser.id,
+    reason: 'loan_income',
+    createdTime: Date.now(),
+    isSeen: false,
+    sourceId: idempotencyKey,
+    sourceType: 'loan',
+    sourceUpdateType: 'updated',
+    sourceUserName: toUser.name,
+    sourceUserUsername: toUser.username,
+    sourceUserAvatarUrl: toUser.avatarUrl,
+    sourceText: income.toString(),
+    sourceTitle: 'Loan',
+  }
+  await notificationRef.set(removeUndefinedProps(notification))
+}
+
 const groupPath = (groupSlug: string) => `/group/${groupSlug}`
 
 export const createChallengeAcceptedNotification = async (

functions/src/create-user.ts

@@ -75,6 +75,7 @@ export const createuser = newEndpoint(opts, async (req, auth) => {
     createdTime: Date.now(),
     profitCached: { daily: 0, weekly: 0, monthly: 0, allTime: 0 },
     creatorVolumeCached: { daily: 0, weekly: 0, monthly: 0, allTime: 0 },
+    nextLoanCached: 0,
     followerCountCached: 0,
     followedCategories: DEFAULT_CATEGORIES,
     shouldShowWelcome: true,

functions/src/index.ts

@@ -11,6 +11,7 @@ export * from './on-create-comment-on-contract'
 export * from './on-view'
 export * from './update-metrics'
 export * from './update-stats'
+export * from './update-loans'
 export * from './backup-db'
 export * from './market-close-notifications'
 export * from './on-create-answer'

functions/src/place-bet.ts

@@ -59,7 +59,6 @@ export const placebet = newEndpoint({}, async (req, auth) => {
     const user = userSnap.data() as User
     if (user.balance < amount) throw new APIError(400, 'Insufficient balance.')
 
-    const loanAmount = 0
     const { closeTime, outcomeType, mechanism, collectedFees, volume } =
       contract
     if (closeTime && Date.now() > closeTime)
@@ -119,7 +118,7 @@ export const placebet = newEndpoint({}, async (req, auth) => {
         const answerDoc = contractDoc.collection('answers').doc(outcome)
         const answerSnap = await trans.get(answerDoc)
         if (!answerSnap.exists) throw new APIError(400, 'Invalid answer')
-        return getNewMultiBetInfo(outcome, amount, contract, loanAmount)
+        return getNewMultiBetInfo(outcome, amount, contract)
       } else if (outcomeType == 'NUMERIC' && mechanism == 'dpm-2') {
         const { outcome, value } = validate(numericSchema, req.body)
         return getNumericBetsInfo(value, outcome, amount, contract)

functions/src/sell-bet.ts

@@ -50,11 +50,12 @@ export const sellbet = newEndpoint({}, async (req, auth) => {
 
     /* eslint-disable-next-line @typescript-eslint/no-non-null-assertion */
     const saleAmount = newBet.sale!.amount
-    const newBalance = user.balance + saleAmount - (bet.loanAmount ?? 0)
+    const newBalance = user.balance + saleAmount + (newBet.loanAmount ?? 0)
     const newBetDoc = firestore.collection(`contracts/${contractId}/bets`).doc()
 
     transaction.update(userDoc, { balance: newBalance })
     transaction.update(betDoc, { isSold: true })
+    // Note: id should have been newBetDoc.id! But leaving it for now so it's consistent.
     transaction.create(newBetDoc, { id: betDoc.id, userId: user.id, ...newBet })
     transaction.update(
       contractDoc,

functions/src/sell-shares.ts

@@ -7,7 +7,7 @@ import { Contract, CPMM_MIN_POOL_QTY } from '../../common/contract'
 import { User } from '../../common/user'
 import { getCpmmSellBetInfo } from '../../common/sell-bet'
 import { addObjects, removeUndefinedProps } from '../../common/util/object'
-import { getValues, log } from './utils'
+import { log } from './utils'
 import { Bet } from '../../common/bet'
 import { floatingEqual, floatingLesserEqual } from '../../common/util/math'
 import { getUnfilledBetsQuery, updateMakers } from './place-bet'
@@ -28,12 +28,16 @@ export const sellshares = newEndpoint({}, async (req, auth) => {
     const contractDoc = firestore.doc(`contracts/${contractId}`)
     const userDoc = firestore.doc(`users/${auth.uid}`)
     const betsQ = contractDoc.collection('bets').where('userId', '==', auth.uid)
-    const [[contractSnap, userSnap], userBets] = await Promise.all([
-      transaction.getAll(contractDoc, userDoc),
-      getValues<Bet>(betsQ), // TODO: why is this not in the transaction??
-    ])
+    const [[contractSnap, userSnap], userBetsSnap, unfilledBetsSnap] =
+      await Promise.all([
+        transaction.getAll(contractDoc, userDoc),
+        transaction.get(betsQ),
+        transaction.get(getUnfilledBetsQuery(contractDoc)),
+      ])
     if (!contractSnap.exists) throw new APIError(400, 'Contract not found.')
     if (!userSnap.exists) throw new APIError(400, 'User not found.')
+    const userBets = userBetsSnap.docs.map((doc) => doc.data() as Bet)
+    const unfilledBets = unfilledBetsSnap.docs.map((doc) => doc.data())
 
     const contract = contractSnap.data() as Contract
     const user = userSnap.data() as User
@@ -45,7 +49,7 @@ export const sellshares = newEndpoint({}, async (req, auth) => {
     if (closeTime && Date.now() > closeTime)
       throw new APIError(400, 'Trading is closed.')
 
-    const prevLoanAmount = sumBy(userBets, (bet) => bet.loanAmount ?? 0)
+    const loanAmount = sumBy(userBets, (bet) => bet.loanAmount ?? 0)
     const betsByOutcome = groupBy(userBets, (bet) => bet.outcome)
     const sharesByOutcome = mapValues(betsByOutcome, (bets) =>
       sumBy(bets, (b) => b.shares)
@@ -77,18 +81,16 @@ export const sellshares = newEndpoint({}, async (req, auth) => {
       throw new APIError(400, `You can only sell up to ${maxShares} shares.`)
 
     const soldShares = Math.min(sharesToSell, maxShares)
-
-    const unfilledBetsSnap = await transaction.get(
-      getUnfilledBetsQuery(contractDoc)
-    )
-    const unfilledBets = unfilledBetsSnap.docs.map((doc) => doc.data())
+    const saleFrac = soldShares / maxShares
+    let loanPaid = saleFrac * loanAmount
+    if (!isFinite(loanPaid)) loanPaid = 0
 
     const { newBet, newPool, newP, fees, makers } = getCpmmSellBetInfo(
       soldShares,
       chosenOutcome,
       contract,
-      prevLoanAmount,
-      unfilledBets
+      unfilledBets,
+      loanPaid
     )
 
     if (
@@ -104,7 +106,7 @@ export const sellshares = newEndpoint({}, async (req, auth) => {
     updateMakers(makers, newBetDoc.id, contractDoc, transaction)
 
     transaction.update(userDoc, {
-      balance: FieldValue.increment(-newBet.amount),
+      balance: FieldValue.increment(-newBet.amount + (newBet.loanAmount ?? 0)),
     })
     transaction.create(newBetDoc, {
       id: newBetDoc.id,

functions/src/update-loans.ts

@@ -0,0 +1,88 @@
+import * as functions from 'firebase-functions'
+import * as admin from 'firebase-admin'
+import { groupBy, keyBy } from 'lodash'
+import { getValues, log, payUser, writeAsync } from './utils'
+import { Bet } from '../../common/bet'
+import { Contract } from '../../common/contract'
+import { PortfolioMetrics, User } from '../../common/user'
+import { getLoanUpdates } from '../../common/loans'
+import { createLoanIncomeNotification } from './create-notification'
+
+const firestore = admin.firestore()
+
+export const updateLoans = functions
+  .runWith({ memory: '2GB', timeoutSeconds: 540 })
+  // Run every Monday.
+  .pubsub.schedule('0 0 * * 1')
+  .timeZone('America/Los_Angeles')
+  .onRun(updateLoansCore)
+
+async function updateLoansCore() {
+  log('Updating loans...')
+
+  const [users, contracts, bets] = await Promise.all([
+    getValues<User>(firestore.collection('users')),
+    getValues<Contract>(
+      firestore.collection('contracts').where('isResolved', '==', false)
+    ),
+    getValues<Bet>(firestore.collectionGroup('bets')),
+  ])
+  log(
+    `Loaded ${users.length} users, ${contracts.length} contracts, and ${bets.length} bets.`
+  )
+  const userPortfolios = await Promise.all(
+    users.map(async (user) => {
+      const portfolio = await getValues<PortfolioMetrics>(
+        firestore
+          .collection(`users/${user.id}/portfolioHistory`)
+          .orderBy('timestamp', 'desc')
+          .limit(1)
+      )
+      return portfolio[0]
+    })
+  )
+  log(`Loaded ${userPortfolios.length} portfolios`)
+  const portfolioByUser = keyBy(userPortfolios, (portfolio) => portfolio.userId)
+
+  const contractsById = Object.fromEntries(
+    contracts.map((contract) => [contract.id, contract])
+  )
+  const betsByUser = groupBy(bets, (bet) => bet.userId)
+  const { betUpdates, userPayouts } = getLoanUpdates(
+    users,
+    contractsById,
+    portfolioByUser,
+    betsByUser
+  )
+
+  log(`${betUpdates.length} bet updates.`)
+
+  const betDocUpdates = betUpdates.map((update) => ({
+    doc: firestore
+      .collection('contracts')
+      .doc(update.contractId)
+      .collection('bets')
+      .doc(update.betId),
+    fields: {
+      loanAmount: update.loanTotal,
+    },
+  }))
+
+  await writeAsync(firestore, betDocUpdates)
+
+  log(`${userPayouts.length} user payouts`)
+
+  await Promise.all(
+    userPayouts.map(({ user, payout }) => payUser(user.id, payout))
+  )
+
+  const today = new Date().toDateString().replace(' ', '-')
+  const key = `loan-notifications-${today}`
+  await Promise.all(
+    userPayouts.map(({ user, payout }) =>
+      createLoanIncomeNotification(user, key, payout)
+    )
+  )
+
+  log('Notifications sent!')
+}

functions/src/update-metrics.ts

@@ -1,6 +1,6 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
-import { groupBy, isEmpty, sum, sumBy } from 'lodash'
+import { groupBy, isEmpty, keyBy, sum, sumBy } from 'lodash'
 import { getValues, log, logMemory, writeAsync } from './utils'
 import { Bet } from '../../common/bet'
 import { Contract } from '../../common/contract'
@@ -8,6 +8,7 @@ import { PortfolioMetrics, User } from '../../common/user'
 import { calculatePayout } from '../../common/calculate'
 import { DAY_MS } from '../../common/util/time'
 import { last } from 'lodash'
+import { getLoanUpdates } from '../../common/loans'
 
 const firestore = admin.firestore()
 
@@ -21,7 +22,9 @@ const computeInvestmentValue = (
     if (bet.sale || bet.isSold) return 0
 
     const payout = calculatePayout(contract, bet, 'MKT')
-    return payout - (bet.loanAmount ?? 0)
+    const value = payout - (bet.loanAmount ?? 0)
+    if (isNaN(value)) return 0
+    return value
   })
 }
 
@@ -71,7 +74,8 @@ export const updateMetricsCore = async () => {
   const contractsByUser = groupBy(contracts, (contract) => contract.creatorId)
   const betsByUser = groupBy(bets, (bet) => bet.userId)
   const portfolioHistoryByUser = groupBy(allPortfolioHistories, (p) => p.userId)
-  const userUpdates = users.map((user) => {
+
+  const userMetrics = users.map((user) => {
     const currentBets = betsByUser[user.id] ?? []
     const portfolioHistory = portfolioHistoryByUser[user.id] ?? []
     const userContracts = contractsByUser[user.id] ?? []
@@ -93,32 +97,56 @@ export const updateMetricsCore = async () => {
       newPortfolio,
       didProfitChange
     )
-
     return {
-      fieldUpdates: {
-        doc: firestore.collection('users').doc(user.id),
-        fields: {
-          creatorVolumeCached: newCreatorVolume,
-          ...(didProfitChange && {
-            profitCached: newProfit,
-          }),
-        },
-      },
-
-      subcollectionUpdates: {
-        doc: firestore
-          .collection('users')
-          .doc(user.id)
-          .collection('portfolioHistory')
-          .doc(),
-        fields: {
-          ...(didProfitChange && {
-            ...newPortfolio,
-          }),
-        },
-      },
+      user,
+      newCreatorVolume,
+      newPortfolio,
+      newProfit,
+      didProfitChange,
     }
   })
+
+  const portfolioByUser = Object.fromEntries(
+    userMetrics.map(({ user, newPortfolio }) => [user.id, newPortfolio])
+  )
+  const { userPayouts } = getLoanUpdates(
+    users,
+    contractsById,
+    portfolioByUser,
+    betsByUser
+  )
+  const nextLoanByUser = keyBy(userPayouts, (payout) => payout.user.id)
+
+  const userUpdates = userMetrics.map(
+    ({ user, newCreatorVolume, newPortfolio, newProfit, didProfitChange }) => {
+      const nextLoanCached = nextLoanByUser[user.id]?.payout ?? 0
+      return {
+        fieldUpdates: {
+          doc: firestore.collection('users').doc(user.id),
+          fields: {
+            creatorVolumeCached: newCreatorVolume,
+            ...(didProfitChange && {
+              profitCached: newProfit,
+            }),
+            nextLoanCached,
+          },
+        },
+
+        subcollectionUpdates: {
+          doc: firestore
+            .collection('users')
+            .doc(user.id)
+            .collection('portfolioHistory')
+            .doc(),
+          fields: {
+            ...(didProfitChange && {
+              ...newPortfolio,
+            }),
+          },
+        },
+      }
+    }
+  )
   await writeAsync(
     firestore,
     userUpdates.map((u) => u.fieldUpdates)
@@ -234,6 +262,6 @@ const calculateNewProfit = (
 }
 
 export const updateMetrics = functions
-  .runWith({ memory: '1GB', timeoutSeconds: 540 })
+  .runWith({ memory: '2GB', timeoutSeconds: 540 })
   .pubsub.schedule('every 15 minutes')
   .onRun(updateMetricsCore)

web/components/profile/betting-streak-modal.tsx

@@ -16,7 +16,7 @@ export function BettingStreakModal(props: {
     <Modal open={isOpen} setOpen={setOpen}>
       <Col className="items-center gap-4 rounded-md bg-white px-8 py-6">
         <span className={'text-8xl'}>🔥</span>
-        <span>Daily betting streaks</span>
+        <span className="text-xl">Daily betting streaks</span>
         <Col className={'gap-2'}>
           <span className={'text-indigo-700'}>• What are they?</span>
           <span className={'ml-2'}>

web/components/profile/loans-modal.tsx

@@ -0,0 +1,47 @@
+import { Modal } from 'web/components/layout/modal'
+import { Col } from 'web/components/layout/col'
+
+export function LoansModal(props: {
+  isOpen: boolean
+  setOpen: (open: boolean) => void
+}) {
+  const { isOpen, setOpen } = props
+
+  return (
+    <Modal open={isOpen} setOpen={setOpen}>
+      <Col className="items-center gap-4 rounded-md bg-white px-8 py-6">
+        <span className={'text-8xl'}>🏦</span>
+        <span className="text-xl">Loans on your bets</span>
+        <Col className={'gap-2'}>
+          <span className={'text-indigo-700'}>• What are loans?</span>
+          <span className={'ml-2'}>
+            Every Monday, get 5% of your total bet amount back as a loan.
+          </span>
+          <span className={'text-indigo-700'}>
+            • Do I have to pay back a loan?
+          </span>
+          <span className={'ml-2'}>
+            Yes, don't worry! You will automatically pay back loans when the
+            market resolves or you sell your bet.
+          </span>
+          <span className={'text-indigo-700'}>
+            • What is the purpose of loans?
+          </span>
+          <span className={'ml-2'}>
+            Loans make it worthwhile to bet on markets that won't resolve for
+            months or years, because your investment won't be locked up as long.
+          </span>
+          <span className={'text-indigo-700'}>• What is an example?</span>
+          <span className={'ml-2'}>
+            For example, if you bet M$100 on "Will I become a millionare?" on
+            Sunday, you will get M$5 back on Monday.
+          </span>
+          <span className={'ml-2'}>
+            Previous loans count against your total bet amount. So, the next
+            week, you would get back 5% of M$95 = M$4.75.
+          </span>
+        </Col>
+      </Col>
+    </Modal>
+  )
+}

web/components/user-page.tsx

@@ -29,6 +29,7 @@ import { formatMoney } from 'common/util/format'
 import { ShareIconButton } from 'web/components/share-icon-button'
 import { ENV_CONFIG } from 'common/envs/constants'
 import { BettingStreakModal } from 'web/components/profile/betting-streak-modal'
+import { LoansModal } from './profile/loans-modal'
 import { REFERRAL_AMOUNT } from 'common/user'
 
 export function UserLink(props: {
@@ -68,6 +69,7 @@ export function UserPage(props: { user: User }) {
   const bannerUrl = user.bannerUrl ?? defaultBannerUrl(user.id)
   const [showConfetti, setShowConfetti] = useState(false)
   const [showBettingStreakModal, setShowBettingStreakModal] = useState(false)
+  const [showLoansModal, setShowLoansModal] = useState(false)
 
   useEffect(() => {
     const claimedMana = router.query['claimed-mana'] === 'yes'
@@ -75,6 +77,9 @@ export function UserPage(props: { user: User }) {
     setShowBettingStreakModal(showBettingStreak)
     setShowConfetti(claimedMana || showBettingStreak)
 
+    const showLoansModel = router.query['show'] === 'loans'
+    setShowLoansModal(showLoansModel)
+
     const query = { ...router.query }
     if (query.claimedMana || query.show) {
       delete query['claimed-mana']
@@ -107,6 +112,9 @@ export function UserPage(props: { user: User }) {
         isOpen={showBettingStreakModal}
         setOpen={setShowBettingStreakModal}
       />
+      {showLoansModal && (
+        <LoansModal isOpen={showLoansModal} setOpen={setShowLoansModal} />
+      )}
       {/* Banner image up top, with an circle avatar overlaid */}
       <div
         className="h-32 w-full bg-cover bg-center sm:h-40"
@@ -128,7 +136,7 @@ export function UserPage(props: { user: User }) {
         <div className="absolute right-0 top-0 mt-2 mr-4">
           {!isCurrentUser && <UserFollowButton userId={user.id} />}
           {isCurrentUser && (
-            <SiteLink className="sm:btn-md btn-sm btn" href="/profile">
+            <SiteLink className="btn-sm btn" href="/profile">
               <PencilIcon className="h-5 w-5" />{' '}
               <div className="ml-2">Edit</div>
             </SiteLink>
@@ -138,9 +146,14 @@ export function UserPage(props: { user: User }) {
 
       {/* Profile details: name, username, bio, and link to twitter/discord */}
       <Col className="mx-4 -mt-6">
-        <Row className={'justify-between'}>
+        <Row className={'flex-wrap justify-between gap-y-2'}>
           <Col>
-            <span className="text-2xl font-bold">{user.name}</span>
+            <span
+              className="text-2xl font-bold"
+              style={{ wordBreak: 'break-word' }}
+            >
+              {user.name}
+            </span>
             <span className="text-gray-500">@{user.username}</span>
           </Col>
           <Col className={'justify-center'}>
@@ -160,9 +173,20 @@ export function UserPage(props: { user: User }) {
                 className={'cursor-pointer items-center text-gray-500'}
                 onClick={() => setShowBettingStreakModal(true)}
               >
-                <span>🔥{user.currentBettingStreak ?? 0}</span>
+                <span>🔥 {user.currentBettingStreak ?? 0}</span>
                 <span>streak</span>
               </Col>
+              <Col
+                className={
+                  'flex-shrink-0 cursor-pointer items-center text-gray-500'
+                }
+                onClick={() => setShowLoansModal(true)}
+              >
+                <span className="text-green-600">
+                  🏦 {formatMoney(user.nextLoanCached ?? 0)}
+                </span>
+                <span>next loan</span>
+              </Col>
             </Row>
           </Col>
         </Row>

web/hooks/use-notifications.ts

@@ -5,7 +5,7 @@ import {
   getNotificationsQuery,
   listenForNotifications,
 } from 'web/lib/firebase/notifications'
-import { groupBy, map } from 'lodash'
+import { groupBy, map, partition } from 'lodash'
 import { useFirestoreQueryData } from '@react-query-firebase/firestore'
 import { NOTIFICATIONS_PER_PAGE } from 'web/pages/notifications'
 
@@ -67,19 +67,14 @@ export function groupNotifications(notifications: Notification[]) {
   const notificationGroupsByDay = groupBy(notifications, (notification) =>
     new Date(notification.createdTime).toDateString()
   )
+  const incomeSourceTypes = ['bonus', 'tip', 'loan', 'betting_streak_bonus']
+
   Object.keys(notificationGroupsByDay).forEach((day) => {
     const notificationsGroupedByDay = notificationGroupsByDay[day]
-    const incomeNotifications = notificationsGroupedByDay.filter(
+    const [incomeNotifications, normalNotificationsGroupedByDay] = partition(
+      notificationsGroupedByDay,
       (notification) =>
-        notification.sourceType === 'bonus' ||
-        notification.sourceType === 'tip' ||
-        notification.sourceType === 'betting_streak_bonus'
-    )
-    const normalNotificationsGroupedByDay = notificationsGroupedByDay.filter(
-      (notification) =>
-        notification.sourceType !== 'bonus' &&
-        notification.sourceType !== 'tip' &&
-        notification.sourceType !== 'betting_streak_bonus'
+        incomeSourceTypes.includes(notification.sourceType ?? '')
     )
     if (incomeNotifications.length > 0) {
       notificationGroups = notificationGroups.concat({

web/pages/notifications.tsx

@@ -388,6 +388,8 @@ function IncomeNotificationItem(props: {
       reasonText = !simple ? `tipped you on` : `in tips on`
     } else if (sourceType === 'betting_streak_bonus') {
       reasonText = 'for your'
+    } else if (sourceType === 'loan' && sourceText) {
+      reasonText = `of your invested bets returned as`
     }
 
     const bettingStreakText =
@@ -401,7 +403,15 @@ function IncomeNotificationItem(props: {
     return (
       <>
         {reasonText}
-        {sourceType === 'betting_streak_bonus' ? (
+        {sourceType === 'loan' ? (
+          simple ? (
+            <span className={'ml-1 font-bold'}>Loan</span>
+          ) : (
+            <SiteLink className={'ml-1 font-bold'} href={'/loans'}>
+              Loan
+            </SiteLink>
+          )
+        ) : sourceType === 'betting_streak_bonus' ? (
           simple ? (
             <span className={'ml-1 font-bold'}>{bettingStreakText}</span>
           ) : (
@@ -445,6 +455,7 @@ function IncomeNotificationItem(props: {
     if (sourceType === 'challenge') return `${sourceSlug}`
     if (sourceType === 'betting_streak_bonus')
       return `/${sourceUserUsername}/?show=betting-streak`
+    if (sourceType === 'loan') return `/${sourceUserUsername}/?show=loans`
     if (sourceContractCreatorUsername && sourceContractSlug)
       return `/${sourceContractCreatorUsername}/${sourceContractSlug}#${getSourceIdForLinkComponent(
         sourceId ?? '',