Change lodash stuff so that it can be tree-shaken out of build (#233)

* Set common package.json sideEffects: false

* Configure SWC to modularize lodash imports

* Import specific lodash functions instead of _

* Add an eslint rule to avoid full lodash import

common/.eslintrc.js

@@ -1,4 +1,5 @@
 module.exports = {
+  plugins: ['lodash'],
   extends: ['eslint:recommended'],
   env: {
     browser: true,
@@ -14,5 +15,6 @@ module.exports = {
   rules: {
     'no-unused-vars': 'off',
     'no-constant-condition': ['error', { checkLoops: false }],
+    'lodash/import-scope': [2, 'member'],
   },
 }

common/antes.ts

@@ -1,3 +1,4 @@
+import { range } from 'lodash'
 import { Bet, NumericBet } from './bet'
 import { getDpmProbability, getValueFromBucket } from './calculate-dpm'
 import {
@@ -11,7 +12,6 @@ import {
 import { User } from './user'
 import { LiquidityProvision } from './liquidity-provision'
 import { noFees } from './fees'
-import * as _ from 'lodash'
 
 export const FIXED_ANTE = 100
 
@@ -127,11 +127,11 @@ export function getNumericAnte(
   const betShares = Math.sqrt(ante ** 2 / bucketCount)
 
   const allOutcomeShares = Object.fromEntries(
-    _.range(0, bucketCount).map((_, i) => [i, betShares])
+    range(0, bucketCount).map((_, i) => [i, betShares])
   )
 
   const allBetAmounts = Object.fromEntries(
-    _.range(0, bucketCount).map((_, i) => [i, betAnte])
+    range(0, bucketCount).map((_, i) => [i, betAnte])
   )
 
   const anteBet: NumericBet = {

common/calculate-cpmm.ts

@@ -1,4 +1,4 @@
-import * as _ from 'lodash'
+import { sum, groupBy, mapValues, sumBy } from 'lodash'
 
 import { Binary, CPMM, FullContract } from './contract'
 import { CREATOR_FEE, Fees, LIQUIDITY_FEE, noFees, PLATFORM_FEE } from './fees'
@@ -278,16 +278,16 @@ export function getCpmmLiquidityPoolWeights(
     return liquidity
   })
 
-  const shareSum = _.sum(liquidityShares)
+  const shareSum = sum(liquidityShares)
 
   const weights = liquidityShares.map((s, i) => ({
     weight: s / shareSum,
     providerId: liquidities[i].userId,
   }))
 
-  const userWeights = _.groupBy(weights, (w) => w.providerId)
+  const userWeights = groupBy(weights, (w) => w.providerId)
-  const totalUserWeights = _.mapValues(userWeights, (userWeight) =>
+  const totalUserWeights = mapValues(userWeights, (userWeight) =>
-    _.sumBy(userWeight, (w) => w.weight)
+    sumBy(userWeight, (w) => w.weight)
   )
   return totalUserWeights
 }

common/calculate-dpm.ts

@@ -1,5 +1,4 @@
-import * as _ from 'lodash'
+import { cloneDeep, range, sum, sumBy, sortBy, mapValues } from 'lodash'
-
 import { Bet, NumericBet } from './bet'
 import {
   Binary,
@@ -24,7 +23,7 @@ export function getDpmOutcomeProbability(
   },
   outcome: string
 ) {
-  const squareSum = _.sumBy(Object.values(totalShares), (shares) => shares ** 2)
+  const squareSum = sumBy(Object.values(totalShares), (shares) => shares ** 2)
   const shares = totalShares[outcome] ?? 0
   return shares ** 2 / squareSum
 }
@@ -32,8 +31,8 @@ export function getDpmOutcomeProbability(
 export function getDpmOutcomeProbabilities(totalShares: {
   [outcome: string]: number
 }) {
-  const squareSum = _.sumBy(Object.values(totalShares), (shares) => shares ** 2)
+  const squareSum = sumBy(Object.values(totalShares), (shares) => shares ** 2)
-  return _.mapValues(totalShares, (shares) => shares ** 2 / squareSum)
+  return mapValues(totalShares, (shares) => shares ** 2 / squareSum)
 }
 
 export function getNumericBets(
@@ -44,20 +43,20 @@ export function getNumericBets(
 ) {
   const { bucketCount } = contract
   const bucketNumber = parseInt(bucket)
-  const buckets = _.range(0, bucketCount)
+  const buckets = range(0, bucketCount)
 
   const mean = bucketNumber / bucketCount
 
   const allDensities = buckets.map((i) =>
     normpdf(i / bucketCount, mean, variance)
   )
-  const densitySum = _.sum(allDensities)
+  const densitySum = sum(allDensities)
 
   const rawBetAmounts = allDensities
     .map((d) => (d / densitySum) * betAmount)
     .map((x) => (x >= 1 / bucketCount ? x : 0))
 
-  const rawSum = _.sum(rawBetAmounts)
+  const rawSum = sum(rawBetAmounts)
   const scaledBetAmounts = rawBetAmounts.map((x) => (x / rawSum) * betAmount)
 
   const bets = scaledBetAmounts
@@ -90,26 +89,24 @@ export const getValueFromBucket = (
 export const getExpectedValue = (contract: NumericContract) => {
   const { bucketCount, min, max, totalShares } = contract
 
-  const totalShareSum = _.sumBy(
+  const totalShareSum = sumBy(
     Object.values(totalShares),
     (shares) => shares ** 2
   )
-  const probs = _.range(0, bucketCount).map(
+  const probs = range(0, bucketCount).map(
     (i) => totalShares[i] ** 2 / totalShareSum
   )
 
-  const values = _.range(0, bucketCount).map(
+  const values = range(0, bucketCount).map(
     (i) =>
       // use mid point within bucket
       0.5 * (min + (i / bucketCount) * (max - min)) +
       0.5 * (min + ((i + 1) / bucketCount) * (max - min))
   )
 
-  const weightedValues = _.range(0, bucketCount).map(
+  const weightedValues = range(0, bucketCount).map((i) => probs[i] * values[i])
-    (i) => probs[i] * values[i]
-  )
 
-  const expectation = _.sum(weightedValues)
+  const expectation = sum(weightedValues)
   const rounded = Math.round(expectation * 1e2) / 1e2
   return rounded
 }
@@ -150,7 +147,7 @@ export function calculateDpmShares(
   bet: number,
   betChoice: string
 ) {
-  const squareSum = _.sumBy(Object.values(totalShares), (shares) => shares ** 2)
+  const squareSum = sumBy(Object.values(totalShares), (shares) => shares ** 2)
   const shares = totalShares[betChoice] ?? 0
 
   const c = 2 * bet * Math.sqrt(squareSum)
@@ -166,9 +163,9 @@ export function calculateNumericDpmShares(
 ) {
   const shares: number[] = []
 
-  totalShares = _.cloneDeep(totalShares)
+  totalShares = cloneDeep(totalShares)
 
-  const order = _.sortBy(
+  const order = sortBy(
     bets.map(([, amount], i) => [amount, i]),
     ([amount]) => amount
   ).map(([, i]) => i)
@@ -190,11 +187,11 @@ export function calculateDpmRawShareValue(
   betChoice: string
 ) {
   const currentValue = Math.sqrt(
-    _.sumBy(Object.values(totalShares), (shares) => shares ** 2)
+    sumBy(Object.values(totalShares), (shares) => shares ** 2)
   )
 
   const postSaleValue = Math.sqrt(
-    _.sumBy(Object.keys(totalShares), (outcome) =>
+    sumBy(Object.keys(totalShares), (outcome) =>
       outcome === betChoice
         ? Math.max(0, totalShares[outcome] - shares) ** 2
         : totalShares[outcome] ** 2
@@ -214,12 +211,12 @@ export function calculateDpmMoneyRatio(
 
   const p = getDpmOutcomeProbability(totalShares, outcome)
 
-  const actual = _.sum(Object.values(pool)) - shareValue
+  const actual = sum(Object.values(pool)) - shareValue
 
   const betAmount = p * amount
 
   const expected =
-    _.sumBy(
+    sumBy(
       Object.keys(totalBets),
       (outcome) =>
         getDpmOutcomeProbability(totalShares, outcome) *
@@ -271,8 +268,8 @@ export function calculateDpmCancelPayout(
   bet: Bet
 ) {
   const { totalBets, pool } = contract
-  const betTotal = _.sum(Object.values(totalBets))
+  const betTotal = sum(Object.values(totalBets))
-  const poolTotal = _.sum(Object.values(pool))
+  const poolTotal = sum(Object.values(pool))
 
   return (bet.amount / betTotal) * poolTotal
 }
@@ -295,7 +292,7 @@ export function calculateStandardDpmPayout(
   const { totalShares, phantomShares, pool } = contract
   if (!totalShares[outcome]) return 0
 
-  const poolTotal = _.sum(Object.values(pool))
+  const poolTotal = sum(Object.values(pool))
 
   const total =
     totalShares[outcome] - (phantomShares ? phantomShares[outcome] : 0)
@@ -356,19 +353,19 @@ function calculateMktDpmPayout(
   let probs: { [outcome: string]: number }
 
   if (resolutions) {
-    const probTotal = _.sum(Object.values(resolutions))
+    const probTotal = sum(Object.values(resolutions))
-    probs = _.mapValues(
+    probs = mapValues(
       totalShares,
       (_, outcome) => (resolutions[outcome] ?? 0) / probTotal
     )
   } else {
-    const squareSum = _.sum(
+    const squareSum = sum(
       Object.values(totalShares).map((shares) => shares ** 2)
     )
-    probs = _.mapValues(totalShares, (shares) => shares ** 2 / squareSum)
+    probs = mapValues(totalShares, (shares) => shares ** 2 / squareSum)
   }
 
-  const weightedShareTotal = _.sumBy(Object.keys(totalShares), (outcome) => {
+  const weightedShareTotal = sumBy(Object.keys(totalShares), (outcome) => {
     return probs[outcome] * totalShares[outcome]
   })
 
@@ -376,7 +373,7 @@ function calculateMktDpmPayout(
 
   const poolFrac =
     outcomeType === 'NUMERIC'
-      ? _.sumBy(
+      ? sumBy(
           Object.keys((bet as NumericBet).allOutcomeShares ?? {}),
           (outcome) => {
             return (
@@ -387,7 +384,7 @@ function calculateMktDpmPayout(
         )
       : (probs[outcome] * shares) / weightedShareTotal
 
-  const totalPool = _.sum(Object.values(pool))
+  const totalPool = sum(Object.values(pool))
   const winnings = poolFrac * totalPool
   return deductDpmFees(amount, winnings)
 }

common/calculate.ts

@@ -1,4 +1,4 @@
-import * as _ from 'lodash'
+import { maxBy } from 'lodash'
 import { Bet } from './bet'
 import {
   calculateCpmmSale,
@@ -180,7 +180,7 @@ export function getContractBetNullMetrics() {
 
 export function getTopAnswer(contract: FreeResponseContract) {
   const { answers } = contract
-  const top = _.maxBy(
+  const top = maxBy(
     answers?.map((answer) => ({
       answer,
       prob: getOutcomeProbability(contract, answer.id),

common/contract.ts

@@ -1,4 +1,3 @@
-import * as _ from 'lodash'
 import { Answer } from './answer'
 import { Fees } from './fees'
 

common/new-bet.ts

@@ -1,4 +1,4 @@
-import * as _ from 'lodash'
+import { sumBy } from 'lodash'
 
 import { Bet, MAX_LOAN_PER_CONTRACT, NumericBet } from './bet'
 import {
@@ -210,7 +210,7 @@ export const getNumericBetsInfo = (
 
 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 prevLoanAmount = sumBy(openBets, (bet) => bet.loanAmount ?? 0)
   const loanAmount = Math.min(
     newBetAmount,
     MAX_LOAN_PER_CONTRACT - prevLoanAmount

common/new-contract.ts

@@ -1,5 +1,4 @@
-import * as _ from 'lodash'
+import { range } from 'lodash'
-
 import { PHANTOM_ANTE } from './antes'
 import {
   Binary,
@@ -131,7 +130,7 @@ const getNumericProps = (
   min: number,
   max: number
 ) => {
-  const buckets = _.range(0, bucketCount).map((i) => i.toString())
+  const buckets = range(0, bucketCount).map((i) => i.toString())
 
   const betAnte = ante / bucketCount
   const pool = Object.fromEntries(buckets.map((answer) => [answer, betAnte]))

common/package.json

@@ -3,6 +3,7 @@
   "version": "1.0.0",
   "private": true,
   "scripts": {},
+  "sideEffects": false,
   "dependencies": {
     "lodash": "4.17.21"
   },

common/payouts-dpm.ts

@@ -1,4 +1,4 @@
-import * as _ from 'lodash'
+import { sum, groupBy, sumBy, mapValues } from 'lodash'
 
 import { Bet, NumericBet } from './bet'
 import { deductDpmFees, getDpmProbability } from './calculate-dpm'
@@ -17,10 +17,10 @@ export const getDpmCancelPayouts = (
   bets: Bet[]
 ) => {
   const { pool } = contract
-  const poolTotal = _.sum(Object.values(pool))
+  const poolTotal = sum(Object.values(pool))
   console.log('resolved N/A, pool M$', poolTotal)
 
-  const betSum = _.sumBy(bets, (b) => b.amount)
+  const betSum = sumBy(bets, (b) => b.amount)
 
   const payouts = bets.map((bet) => ({
     userId: bet.userId,
@@ -42,8 +42,8 @@ export const getDpmStandardPayouts = (
 ) => {
   const winningBets = bets.filter((bet) => bet.outcome === outcome)
 
-  const poolTotal = _.sum(Object.values(contract.pool))
+  const poolTotal = sum(Object.values(contract.pool))
-  const totalShares = _.sumBy(winningBets, (b) => b.shares)
+  const totalShares = sumBy(winningBets, (b) => b.shares)
 
   const payouts = winningBets.map(({ userId, amount, shares }) => {
     const winnings = (shares / totalShares) * poolTotal
@@ -54,7 +54,7 @@ export const getDpmStandardPayouts = (
     return { userId, profit, payout }
   })
 
-  const profits = _.sumBy(payouts, (po) => Math.max(0, po.profit))
+  const profits = sumBy(payouts, (po) => Math.max(0, po.profit))
   const creatorFee = DPM_CREATOR_FEE * profits
   const platformFee = DPM_PLATFORM_FEE * profits
 
@@ -93,10 +93,10 @@ export const getNumericDpmPayouts = (
   contract: FullContract<DPM, any>,
   bets: NumericBet[]
 ) => {
-  const totalShares = _.sumBy(bets, (bet) => bet.allOutcomeShares[outcome] ?? 0)
+  const totalShares = sumBy(bets, (bet) => bet.allOutcomeShares[outcome] ?? 0)
   const winningBets = bets.filter((bet) => !!bet.allOutcomeShares[outcome])
 
-  const poolTotal = _.sum(Object.values(contract.pool))
+  const poolTotal = sum(Object.values(contract.pool))
 
   const payouts = winningBets.map(
     ({ userId, allBetAmounts, allOutcomeShares }) => {
@@ -112,7 +112,7 @@ export const getNumericDpmPayouts = (
     }
   )
 
-  const profits = _.sumBy(payouts, (po) => Math.max(0, po.profit))
+  const profits = sumBy(payouts, (po) => Math.max(0, po.profit))
   const creatorFee = DPM_CREATOR_FEE * profits
   const platformFee = DPM_PLATFORM_FEE * profits
 
@@ -156,7 +156,7 @@ export const getDpmMktPayouts = (
       ? getDpmProbability(contract.totalShares)
       : resolutionProbability
 
-  const weightedShareTotal = _.sumBy(bets, (b) =>
+  const weightedShareTotal = sumBy(bets, (b) =>
     b.outcome === 'YES' ? p * b.shares : (1 - p) * b.shares
   )
 
@@ -170,7 +170,7 @@ export const getDpmMktPayouts = (
     return { userId, profit, payout }
   })
 
-  const profits = _.sumBy(payouts, (po) => Math.max(0, po.profit))
+  const profits = sumBy(payouts, (po) => Math.max(0, po.profit))
 
   const creatorFee = DPM_CREATOR_FEE * profits
   const platformFee = DPM_PLATFORM_FEE * profits
@@ -210,15 +210,15 @@ export const getPayoutsMultiOutcome = (
   contract: FullContract<DPM, Multi | FreeResponse>,
   bets: Bet[]
 ) => {
-  const poolTotal = _.sum(Object.values(contract.pool))
+  const poolTotal = sum(Object.values(contract.pool))
   const winningBets = bets.filter((bet) => resolutions[bet.outcome])
 
-  const betsByOutcome = _.groupBy(winningBets, (bet) => bet.outcome)
+  const betsByOutcome = groupBy(winningBets, (bet) => bet.outcome)
-  const sharesByOutcome = _.mapValues(betsByOutcome, (bets) =>
+  const sharesByOutcome = mapValues(betsByOutcome, (bets) =>
-    _.sumBy(bets, (bet) => bet.shares)
+    sumBy(bets, (bet) => bet.shares)
   )
 
-  const probTotal = _.sum(Object.values(resolutions))
+  const probTotal = sum(Object.values(resolutions))
 
   const payouts = winningBets.map(({ userId, outcome, amount, shares }) => {
     const prob = resolutions[outcome] / probTotal
@@ -229,7 +229,7 @@ export const getPayoutsMultiOutcome = (
     return { userId, profit, payout }
   })
 
-  const profits = _.sumBy(payouts, (po) => po.profit)
+  const profits = sumBy(payouts, (po) => po.profit)
 
   const creatorFee = DPM_CREATOR_FEE * profits
   const platformFee = DPM_PLATFORM_FEE * profits

common/payouts-fixed.ts

@@ -1,4 +1,4 @@
-import * as _ from 'lodash'
+import { sum } from 'lodash'
 
 import { Bet } from './bet'
 import { getProbability } from './calculate'
@@ -50,7 +50,7 @@ export const getStandardFixedPayouts = (
     'pool',
     contract.pool[outcome],
     'payouts',
-    _.sum(payouts),
+    sum(payouts),
     'creator fee',
     creatorPayout
   )
@@ -105,7 +105,7 @@ export const getMktFixedPayouts = (
     'pool',
     p * contract.pool.YES + (1 - p) * contract.pool.NO,
     'payouts',
-    _.sum(payouts),
+    sum(payouts),
     'creator fee',
     creatorPayout
   )

common/payouts.ts

@@ -1,4 +1,4 @@
-import * as _ from 'lodash'
+import { sumBy, groupBy, mapValues } from 'lodash'
 
 import { Bet, NumericBet } from './bet'
 import {
@@ -32,16 +32,19 @@ export type Payout = {
 
 export const getLoanPayouts = (bets: Bet[]): Payout[] => {
   const betsWithLoans = bets.filter((bet) => bet.loanAmount)
-  const betsByUser = _.groupBy(betsWithLoans, (bet) => bet.userId)
+  const betsByUser = groupBy(betsWithLoans, (bet) => bet.userId)
-  const loansByUser = _.mapValues(betsByUser, (bets) =>
+  const loansByUser = mapValues(betsByUser, (bets) =>
-    _.sumBy(bets, (bet) => -(bet.loanAmount ?? 0))
+    sumBy(bets, (bet) => -(bet.loanAmount ?? 0))
   )
-  return _.toPairs(loansByUser).map(([userId, payout]) => ({ userId, payout }))
+  return Object.entries(loansByUser).map(([userId, payout]) => ({
+    userId,
+    payout,
+  }))
 }
 
 export const groupPayoutsByUser = (payouts: Payout[]) => {
-  const groups = _.groupBy(payouts, (payout) => payout.userId)
+  const groups = groupBy(payouts, (payout) => payout.userId)
-  return _.mapValues(groups, (group) => _.sumBy(group, (g) => g.payout))
+  return mapValues(groups, (group) => sumBy(group, (g) => g.payout))
 }
 
 export type PayoutInfo = {

common/recommended-contracts.ts

@@ -1,4 +1,4 @@
-import * as _ from 'lodash'
+import { union, sum, sumBy, sortBy, groupBy, mapValues } from 'lodash'
 import { Bet } from './bet'
 import { Contract } from './contract'
 import { ClickEvent } from './tracking'
@@ -21,13 +21,13 @@ export const getRecommendedContracts = (
 
   const yourWordFrequency = contractsToWordFrequency(yourContracts)
   const otherWordFrequency = contractsToWordFrequency(notYourContracts)
-  const words = _.union(
+  const words = union(
     Object.keys(yourWordFrequency),
     Object.keys(otherWordFrequency)
   )
 
-  const yourWeightedFrequency = _.fromPairs(
+  const yourWeightedFrequency = Object.fromEntries(
-    _.map(words, (word) => {
+    words.map((word) => {
       const [yourFreq, otherFreq] = [
         yourWordFrequency[word] ?? 0,
         otherWordFrequency[word] ?? 0,
@@ -47,7 +47,7 @@ export const getRecommendedContracts = (
   const scoredContracts = contracts.map((contract) => {
     const wordFrequency = contractToWordFrequency(contract)
 
-    const score = _.sumBy(Object.keys(wordFrequency), (word) => {
+    const score = sumBy(Object.keys(wordFrequency), (word) => {
       const wordFreq = wordFrequency[word] ?? 0
       const weight = yourWeightedFrequency[word] ?? 0
       return wordFreq * weight
@@ -59,7 +59,7 @@ export const getRecommendedContracts = (
     }
   })
 
-  return _.sortBy(scoredContracts, (scored) => -scored.score).map(
+  return sortBy(scoredContracts, (scored) => -scored.score).map(
     (scored) => scored.contract
   )
 }
@@ -87,8 +87,8 @@ const getWordsCount = (text: string) => {
 }
 
 const toFrequency = (counts: { [word: string]: number }) => {
-  const total = _.sum(Object.values(counts))
+  const total = sum(Object.values(counts))
-  return _.mapValues(counts, (count) => count / total)
+  return mapValues(counts, (count) => count / total)
 }
 
 const contractToWordFrequency = (contract: Contract) =>
@@ -108,8 +108,8 @@ export const getWordScores = (
   clicks: ClickEvent[],
   bets: Bet[]
 ) => {
-  const contractClicks = _.groupBy(clicks, (click) => click.contractId)
+  const contractClicks = groupBy(clicks, (click) => click.contractId)
-  const contractBets = _.groupBy(bets, (bet) => bet.contractId)
+  const contractBets = groupBy(bets, (bet) => bet.contractId)
 
   const yourContracts = contracts.filter(
     (c) =>
@@ -117,9 +117,7 @@ export const getWordScores = (
   )
   const yourTfIdf = calculateContractTfIdf(yourContracts)
 
-  const contractWordScores = _.mapValues(
+  const contractWordScores = mapValues(yourTfIdf, (wordsTfIdf, contractId) => {
-    yourTfIdf,
-    (wordsTfIdf, contractId) => {
     const viewCount = contractViewCounts[contractId] ?? 0
     const clickCount = contractClicks[contractId]?.length ?? 0
     const betCount = contractBets[contractId]?.length ?? 0
@@ -128,14 +126,13 @@ export const getWordScores = (
       -1 * Math.log(viewCount + 1) +
       10 * Math.log(betCount + clickCount / 4 + 1)
 
-      return _.mapValues(wordsTfIdf, (tfIdf) => tfIdf * factor)
+    return mapValues(wordsTfIdf, (tfIdf) => tfIdf * factor)
-    }
+  })
-  )
 
   const wordScores = Object.values(contractWordScores).reduce(addObjects, {})
   const minScore = Math.min(...Object.values(wordScores))
   const maxScore = Math.max(...Object.values(wordScores))
-  const normalizedWordScores = _.mapValues(
+  const normalizedWordScores = mapValues(
     wordScores,
     (score) => (score - minScore) / (maxScore - minScore)
   )
@@ -156,7 +153,7 @@ export function getContractScore(
   if (Object.keys(wordScores).length === 0) return 1
 
   const wordFrequency = contractToWordFrequency(contract)
-  const score = _.sumBy(Object.keys(wordFrequency), (word) => {
+  const score = sumBy(Object.keys(wordFrequency), (word) => {
     const wordFreq = wordFrequency[word] ?? 0
     const weight = wordScores[word] ?? 0
     return wordFreq * weight
@@ -178,11 +175,13 @@ function calculateContractTfIdf(contracts: Contract[]) {
     }
   }
 
-  const wordIdf = _.mapValues(wordsCount, (count) =>
+  const wordIdf = mapValues(wordsCount, (count) =>
     Math.log(contracts.length / count)
   )
-  const contractWordsTfIdf = _.map(contractFreq, (wordFreq) =>
+  const contractWordsTfIdf = contractFreq.map((wordFreq) =>
-    _.mapValues(wordFreq, (freq, word) => freq * wordIdf[word])
+    mapValues(wordFreq, (freq, word) => freq * wordIdf[word])
+  )
+  return Object.fromEntries(
+    contracts.map((c, i) => [c.id, contractWordsTfIdf[i]])
   )
-  return _.fromPairs(contracts.map((c, i) => [c.id, contractWordsTfIdf[i]]))
 }

common/scoring.ts

@@ -1,13 +1,13 @@
-import * as _ from 'lodash'
+import { groupBy, sumBy, mapValues, partition } from 'lodash'
 
 import { Bet } from './bet'
 import { Binary, Contract, FullContract } from './contract'
 import { getPayouts } from './payouts'
 
 export function scoreCreators(contracts: Contract[], bets: Bet[][]) {
-  const creatorScore = _.mapValues(
+  const creatorScore = mapValues(
-    _.groupBy(contracts, ({ creatorId }) => creatorId),
+    groupBy(contracts, ({ creatorId }) => creatorId),
-    (contracts) => _.sumBy(contracts, ({ pool }) => pool.YES + pool.NO)
+    (contracts) => sumBy(contracts, ({ pool }) => pool.YES + pool.NO)
   )
 
   return creatorScore
@@ -30,7 +30,7 @@ export function scoreUsersByContract(
 ) {
   const { resolution, resolutionProbability } = contract
 
-  const [closedBets, openBets] = _.partition(
+  const [closedBets, openBets] = partition(
     bets,
     (bet) => bet.isSold || bet.sale
   )
@@ -58,9 +58,9 @@ export function scoreUsersByContract(
 
   const netPayouts = [...resolvePayouts, ...salePayouts, ...investments]
 
-  const userScore = _.mapValues(
+  const userScore = mapValues(
-    _.groupBy(netPayouts, (payout) => payout.userId),
+    groupBy(netPayouts, (payout) => payout.userId),
-    (payouts) => _.sumBy(payouts, ({ payout }) => payout)
+    (payouts) => sumBy(payouts, ({ payout }) => payout)
   )
 
   return userScore

common/util/object.ts

@@ -1,4 +1,4 @@
-import * as _ from 'lodash'
+import { union } from 'lodash'
 
 export const removeUndefinedProps = <T>(obj: T): T => {
   let newObj: any = {}
@@ -14,7 +14,7 @@ export const addObjects = <T extends { [key: string]: number }>(
   obj1: T,
   obj2: T
 ) => {
-  const keys = _.union(Object.keys(obj1), Object.keys(obj2))
+  const keys = union(Object.keys(obj1), Object.keys(obj2))
   const newObj = {} as any
 
   for (let key of keys) {

functions/.eslintrc.js

@@ -1,4 +1,5 @@
 module.exports = {
+  plugins: ['lodash'],
   extends: ['eslint:recommended'],
   ignorePatterns: ['lib'],
   env: {
@@ -17,5 +18,6 @@ module.exports = {
   rules: {
     'no-unused-vars': 'off',
     'no-constant-condition': ['error', { checkLoops: false }],
+    'lodash/import-scope': [2, 'member'],
   },
 }

functions/src/create-fold.ts

@@ -1,6 +1,5 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { getUser } from './utils'
 import { Contract } from '../../common/contract'
@@ -34,7 +33,7 @@ export const createFold = functions.runWith({ minInstances: 1 }).https.onCall(
       return { status: 'error', message: 'About must be a string' }
     about = about.trim().slice(0, 140)
 
-    if (!_.isArray(tags))
+    if (!Array.isArray(tags))
       return { status: 'error', message: 'Tags must be an array of strings' }
 
     console.log(

functions/src/emails.ts

@@ -1,5 +1,3 @@
-import * as _ from 'lodash'
-
 import { DOMAIN, PROJECT_ID } from '../../common/envs/constants'
 import { Answer } from '../../common/answer'
 import { Bet } from '../../common/bet'

functions/src/on-create-bet.ts

@@ -1,6 +1,5 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { getContract } from './utils'
 import { Bet } from '../../common/bet'

functions/src/on-create-comment.ts

@@ -1,6 +1,6 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { uniq } from 'lodash'
 
 import { getContract, getUser, getValues } from './utils'
 import { Comment } from '../../common/comment'
@@ -60,7 +60,7 @@ export const onCreateComment = functions.firestore
       firestore.collection('contracts').doc(contractId).collection('comments')
     )
 
-    const recipientUserIds = _.uniq([
+    const recipientUserIds = uniq([
       contract.creatorId,
       ...comments.map((comment) => comment.userId),
     ]).filter((id) => id !== comment.userId)

functions/src/redeem-shares.ts

@@ -1,5 +1,5 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { partition, sumBy } from 'lodash'
 
 import { Bet } from '../../common/bet'
 import { getProbability } from '../../common/calculate'
@@ -25,14 +25,14 @@ export const redeemShares = async (userId: string, contractId: string) => {
         .where('userId', '==', userId)
     )
     const bets = betsSnap.docs.map((doc) => doc.data() as Bet)
-    const [yesBets, noBets] = _.partition(bets, (b) => b.outcome === 'YES')
+    const [yesBets, noBets] = partition(bets, (b) => b.outcome === 'YES')
-    const yesShares = _.sumBy(yesBets, (b) => b.shares)
+    const yesShares = sumBy(yesBets, (b) => b.shares)
-    const noShares = _.sumBy(noBets, (b) => b.shares)
+    const noShares = sumBy(noBets, (b) => b.shares)
 
     const amount = Math.min(yesShares, noShares)
     if (amount <= 0) return
 
-    const prevLoanAmount = _.sumBy(bets, (bet) => bet.loanAmount ?? 0)
+    const prevLoanAmount = sumBy(bets, (bet) => bet.loanAmount ?? 0)
     const loanPaid = Math.min(prevLoanAmount, amount)
     const netAmount = amount - loanPaid
 

functions/src/resolve-market.ts

@@ -1,6 +1,6 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { difference, uniq, mapValues, groupBy, sumBy } from 'lodash'
 
 import { Contract } from '../../common/contract'
 import { User } from '../../common/user'
@@ -187,13 +187,13 @@ const sendResolutionEmails = async (
   resolutionProbability?: number,
   resolutions?: { [outcome: string]: number }
 ) => {
-  const nonWinners = _.difference(
+  const nonWinners = difference(
-    _.uniq(openBets.map(({ userId }) => userId)),
+    uniq(openBets.map(({ userId }) => userId)),
     Object.keys(userPayouts)
   )
-  const investedByUser = _.mapValues(
+  const investedByUser = mapValues(
-    _.groupBy(openBets, (bet) => bet.userId),
+    groupBy(openBets, (bet) => bet.userId),
-    (bets) => _.sumBy(bets, (bet) => bet.amount)
+    (bets) => sumBy(bets, (bet) => bet.amount)
   )
   const emailPayouts = [
     ...Object.entries(userPayouts),

functions/src/scripts/cache-views.ts

@@ -1,5 +1,4 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()

functions/src/scripts/change-user-info.ts

@@ -1,5 +1,4 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()

functions/src/scripts/correct-bet-probability.ts

@@ -1,5 +1,5 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { sortBy } from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()
@@ -20,7 +20,7 @@ async function migrateContract(
     .get()
     .then((snap) => snap.docs.map((bet) => bet.data() as Bet))
 
-  const lastBet = _.sortBy(bets, (bet) => -bet.createdTime)[0]
+  const lastBet = sortBy(bets, (bet) => -bet.createdTime)[0]
   if (lastBet) {
     const probAfter = getDpmProbability(contract.totalShares)
 

functions/src/scripts/create-private-users.ts

@@ -1,5 +1,4 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()

functions/src/scripts/get-json-dump.ts

@@ -1,5 +1,4 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 import * as fs from 'fs'
 
 import { initAdmin } from './script-init'

functions/src/scripts/lowercase-fold-tags.ts

@@ -1,5 +1,5 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { uniq } from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()
@@ -19,7 +19,7 @@ async function lowercaseFoldTags() {
     const foldRef = firestore.doc(`folds/${fold.id}`)
 
     const { tags } = fold
-    const lowercaseTags = _.uniq(tags.map((tag) => tag.toLowerCase()))
+    const lowercaseTags = uniq(tags.map((tag) => tag.toLowerCase()))
 
     console.log('Adding lowercase tags', fold.slug, lowercaseTags)
 

functions/src/scripts/make-contracts-public.ts

@@ -1,5 +1,4 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()

functions/src/scripts/migrate-contract.ts

@@ -1,5 +1,5 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { sumBy } from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()
@@ -25,8 +25,8 @@ async function migrateContract(contractRef: DocRef, contract: Contract) {
     .then((snap) => snap.docs.map((bet) => bet.data() as Bet))
 
   const totalShares = {
-    YES: _.sumBy(bets, (bet) => (bet.outcome === 'YES' ? bet.shares : 0)),
+    YES: sumBy(bets, (bet) => (bet.outcome === 'YES' ? bet.shares : 0)),
-    NO: _.sumBy(bets, (bet) => (bet.outcome === 'NO' ? bet.shares : 0)),
+    NO: sumBy(bets, (bet) => (bet.outcome === 'NO' ? bet.shares : 0)),
   }
 
   await contractRef.update({ totalShares })

functions/src/scripts/migrate-to-cfmm.ts

@@ -1,5 +1,5 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { sortBy } from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()
@@ -48,7 +48,7 @@ async function recalculateContract(contractRef: DocRef, isCommit = false) {
 
     const betsRef = contractRef.collection('bets')
     const betDocs = await transaction.get(betsRef)
-    const bets = _.sortBy(
+    const bets = sortBy(
       betDocs.docs.map((d) => d.data() as Bet),
       (b) => b.createdTime
     )

functions/src/scripts/migrate-to-dpm-2.ts

@@ -1,5 +1,5 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { sortBy, sumBy } from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()
@@ -35,7 +35,7 @@ async function recalculateContract(
     const contract = contractDoc.data() as FullContract<DPM, Binary>
 
     const betDocs = await transaction.get(contractRef.collection('bets'))
-    const bets = _.sortBy(
+    const bets = sortBy(
       betDocs.docs.map((d) => d.data() as Bet),
       (b) => b.createdTime
     )
@@ -43,8 +43,8 @@ async function recalculateContract(
     const phantomAnte = startPool.YES + startPool.NO
 
     const leftovers =
-      _.sumBy(bets, (b) => b.amount) -
+      sumBy(bets, (b) => b.amount) -
-      _.sumBy(bets, (b) => {
+      sumBy(bets, (b) => {
         if (!b.sale) return b.amount
         const soldBet = bets.find((bet) => bet.id === b.sale?.betId)
         return soldBet?.amount || 0

functions/src/scripts/pay-out-contract-again.ts

@@ -1,5 +1,5 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { flatten, groupBy, sumBy, mapValues } from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()
@@ -35,12 +35,12 @@ async function checkIfPayOutAgain(contractRef: DocRef, contract: Contract) {
     )
 
     const loanPayouts = getLoanPayouts(openBets)
-    const groups = _.groupBy(
+    const groups = groupBy(
       [...payouts, ...loanPayouts],
       (payout) => payout.userId
     )
-    const userPayouts = _.mapValues(groups, (group) =>
+    const userPayouts = mapValues(groups, (group) =>
-      _.sumBy(group, (g) => g.payout)
+      sumBy(group, (g) => g.payout)
     )
 
     const entries = Object.entries(userPayouts)
@@ -93,7 +93,7 @@ async function payOutContractAgain() {
     )
   )
 
-  const flattened = _.flatten(toPayOutAgain.map((d) => d.toBePaidOut))
+  const flattened = flatten(toPayOutAgain.map((d) => d.toBePaidOut))
 
   for (const [userId, payout] of flattened) {
     console.log('Paying out', userId, payout)

functions/src/scripts/recalculate-contract-totals.ts

@@ -1,5 +1,5 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { sumBy } from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()
@@ -20,13 +20,13 @@ async function recalculateContract(contractRef: DocRef, contract: Contract) {
   const openBets = bets.filter((b) => !b.isSold && !b.sale)
 
   const totalShares = {
-    YES: _.sumBy(openBets, (bet) => (bet.outcome === 'YES' ? bet.shares : 0)),
+    YES: sumBy(openBets, (bet) => (bet.outcome === 'YES' ? bet.shares : 0)),
-    NO: _.sumBy(openBets, (bet) => (bet.outcome === 'NO' ? bet.shares : 0)),
+    NO: sumBy(openBets, (bet) => (bet.outcome === 'NO' ? bet.shares : 0)),
   }
 
   const totalBets = {
-    YES: _.sumBy(openBets, (bet) => (bet.outcome === 'YES' ? bet.amount : 0)),
+    YES: sumBy(openBets, (bet) => (bet.outcome === 'YES' ? bet.amount : 0)),
-    NO: _.sumBy(openBets, (bet) => (bet.outcome === 'NO' ? bet.amount : 0)),
+    NO: sumBy(openBets, (bet) => (bet.outcome === 'NO' ? bet.amount : 0)),
   }
 
   await contractRef.update({ totalShares, totalBets })

functions/src/scripts/remove-answer-ante.ts

@@ -1,5 +1,4 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()

functions/src/scripts/rename-user-contracts.ts

@@ -1,5 +1,4 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()

functions/src/scripts/update-contract-tags.ts

@@ -1,5 +1,5 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { uniq } from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()
@@ -19,7 +19,7 @@ async function updateContractTags() {
   for (const contract of contracts) {
     const contractRef = firestore.doc(`contracts/${contract.id}`)
 
-    const tags = _.uniq([
+    const tags = uniq([
       ...parseTags(contract.question + contract.description),
       ...(contract.tags ?? []),
     ])

functions/src/scripts/update-feed.ts

@@ -1,5 +1,4 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()

functions/src/scripts/update-last-comment-time.ts

@@ -1,5 +1,4 @@
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { initAdmin } from './script-init'
 initAdmin()

functions/src/sell-shares.ts

@@ -1,4 +1,4 @@
-import * as _ from 'lodash'
+import { partition, sumBy } from 'lodash'
 import * as admin from 'firebase-admin'
 import * as functions from 'firebase-functions'
 
@@ -51,15 +51,15 @@ export const sellShares = functions.runWith({ minInstances: 1 }).https.onCall(
         contractDoc.collection('bets').where('userId', '==', userId)
       )
 
-      const prevLoanAmount = _.sumBy(userBets, (bet) => bet.loanAmount ?? 0)
+      const prevLoanAmount = sumBy(userBets, (bet) => bet.loanAmount ?? 0)
 
-      const [yesBets, noBets] = _.partition(
+      const [yesBets, noBets] = partition(
         userBets ?? [],
         (bet) => bet.outcome === 'YES'
       )
       const [yesShares, noShares] = [
-        _.sumBy(yesBets, (bet) => bet.shares),
+        sumBy(yesBets, (bet) => bet.shares),
-        _.sumBy(noBets, (bet) => bet.shares),
+        sumBy(noBets, (bet) => bet.shares),
       ]
 
       const maxShares = outcome === 'YES' ? yesShares : noShares

functions/src/unsubscribe.ts

@@ -1,6 +1,5 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 import { getUser } from './utils'
 import { PrivateUser } from '../../common/user'
 

functions/src/update-contract-metrics.ts

@@ -1,6 +1,6 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { sumBy } from 'lodash'
 
 import { getValues } from './utils'
 import { Contract } from '../../common/contract'
@@ -39,5 +39,5 @@ const computeVolumeFrom = async (contract: Contract, timeAgoMs: number) => {
       .where('createdTime', '>', Date.now() - timeAgoMs)
   )
 
-  return _.sumBy(bets, (bet) => (bet.isRedemption ? 0 : Math.abs(bet.amount)))
+  return sumBy(bets, (bet) => (bet.isRedemption ? 0 : Math.abs(bet.amount)))
 }

functions/src/update-feed.ts

@@ -1,6 +1,6 @@
-import * as _ from 'lodash'
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
+import { shuffle, sortBy } from 'lodash'
 
 import { getValue, getValues } from './utils'
 import { Contract } from '../../common/contract'
@@ -30,7 +30,7 @@ const BATCH_SIZE = 30
 const MAX_BATCHES = 50
 
 const getUserBatches = async () => {
-  const users = _.shuffle(await getValues<User>(firestore.collection('users')))
+  const users = shuffle(await getValues<User>(firestore.collection('users')))
   let userBatches: User[][] = []
   for (let i = 0; i < users.length; i += BATCH_SIZE) {
     userBatches.push(users.slice(i, i + BATCH_SIZE))
@@ -128,7 +128,7 @@ export const computeFeed = async (user: User, contracts: Contract[]) => {
     return [contract, score] as [Contract, number]
   })
 
-  const sortedContracts = _.sortBy(
+  const sortedContracts = sortBy(
     scoredContracts,
     ([_, score]) => score
   ).reverse()

functions/src/update-recommendations.ts

@@ -1,6 +1,5 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
 
 import { getValue, getValues } from './utils'
 import { Contract } from '../../common/contract'

functions/src/update-user-metrics.ts

@@ -1,6 +1,6 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
-import * as _ from 'lodash'
+import { sum, sumBy } from 'lodash'
 
 import { getValues } from './utils'
 import { Contract } from '../../common/contract'
@@ -19,7 +19,7 @@ export const updateUserMetrics = functions.pubsub
       getValues<Contract>(firestore.collection('contracts')),
     ])
 
-    const contractsDict = _.fromPairs(
+    const contractsDict = Object.fromEntries(
       contracts.map((contract) => [contract.id, contract])
     )
 
@@ -43,12 +43,12 @@ export const updateUserMetrics = functions.pubsub
 
 const computeInvestmentValue = async (
   user: User,
-  contractsDict: _.Dictionary<Contract>
+  contractsDict: { [k: string]: Contract }
 ) => {
   const query = firestore.collectionGroup('bets').where('userId', '==', user.id)
   const bets = await getValues<Bet>(query)
 
-  return _.sumBy(bets, (bet) => {
+  return sumBy(bets, (bet) => {
     const contract = contractsDict[bet.contractId]
     if (!contract || contract.isResolved) return 0
     if (bet.sale || bet.isSold) return 0
@@ -60,20 +60,20 @@ const computeInvestmentValue = async (
 
 const computeTotalPool = async (
   user: User,
-  contractsDict: _.Dictionary<Contract>
+  contractsDict: { [k: string]: Contract }
 ) => {
   const creatorContracts = Object.values(contractsDict).filter(
     (contract) => contract.creatorId === user.id
   )
   const pools = creatorContracts.map((contract) =>
-    _.sum(Object.values(contract.pool))
+    sum(Object.values(contract.pool))
   )
-  return _.sum(pools)
+  return sum(pools)
 }
 
 const computeVolume = async (contract: Contract) => {
   const bets = await getValues<Bet>(
     firestore.collection(`contracts/${contract.id}/bets`)
   )
-  return _.sumBy(bets, (bet) => Math.abs(bet.amount))
+  return sumBy(bets, (bet) => Math.abs(bet.amount))
 }

package.json

@@ -9,10 +9,11 @@
   "scripts": {},
   "dependencies": {},
   "devDependencies": {
-    "typescript": "4.6.4",
     "@typescript-eslint/eslint-plugin": "5.25.0",
     "@typescript-eslint/parser": "5.25.0",
     "eslint": "8.15.0",
-    "prettier": "2.5.0"
+    "eslint-plugin-lodash": "^7.4.0",
+    "prettier": "2.5.0",
+    "typescript": "4.6.4"
   }
 }

web/.eslintrc.js

@@ -1,9 +1,10 @@
 module.exports = {
   parser: '@typescript-eslint/parser',
+  plugins: ['lodash'],
   extends: ['plugin:react-hooks/recommended', 'plugin:@next/next/recommended'],
   rules: {
-    // Add or disable rules here.
     '@next/next/no-img-element': 'off',
     '@next/next/no-typos': 'off',
+    'lodash/import-scope': [2, 'member'],
   },
 }

web/components/analytics/charts.tsx

@@ -1,6 +1,6 @@
 import { Point, ResponsiveLine } from '@nivo/line'
 import dayjs from 'dayjs'
-import _ from 'lodash'
+import { zip } from 'lodash'
 import { useWindowSize } from 'web/hooks/use-window-size'
 import { Col } from '../layout/col'
 
@@ -16,7 +16,7 @@ export function DailyCountChart(props: {
     dayjs(startDate).add(i, 'day').toDate()
   )
 
-  const points = _.zip(dates, dailyCounts).map(([date, betCount]) => ({
+  const points = zip(dates, dailyCounts).map(([date, betCount]) => ({
     x: date,
     y: betCount,
   }))
@@ -68,7 +68,7 @@ export function DailyPercentChart(props: {
     dayjs(startDate).add(i, 'day').toDate()
   )
 
-  const points = _.zip(dates, dailyPercent).map(([date, betCount]) => ({
+  const points = zip(dates, dailyPercent).map(([date, betCount]) => ({
     x: date,
     y: betCount,
   }))

web/components/answers/answer-resolve-panel.tsx

@@ -1,5 +1,5 @@
 import clsx from 'clsx'
-import _ from 'lodash'
+import { sum, mapValues } from 'lodash'
 import { useState } from 'react'
 
 import { DPM, FreeResponse, FullContract } from 'common/contract'
@@ -30,8 +30,8 @@ export function AnswerResolvePanel(props: {
 
     setIsSubmitting(true)
 
-    const totalProb = _.sum(Object.values(chosenAnswers))
+    const totalProb = sum(Object.values(chosenAnswers))
-    const normalizedProbs = _.mapValues(
+    const normalizedProbs = mapValues(
       chosenAnswers,
       (prob) => (100 * prob) / totalProb
     )

web/components/answers/answers-graph.tsx

@@ -1,7 +1,7 @@
 import { DatumValue } from '@nivo/core'
 import { ResponsiveLine } from '@nivo/line'
 import dayjs from 'dayjs'
-import _ from 'lodash'
+import { groupBy, sortBy, sumBy } from 'lodash'
 import { memo } from 'react'
 
 import { Bet } from 'common/bet'
@@ -48,7 +48,7 @@ export const AnswersGraph = memo(function AnswersGraph(props: {
         // to the right.
         latestTime.add(1, 'month').valueOf()
 
-  const times = _.sortBy([
+  const times = sortBy([
     createdTime,
     ...bets.map((bet) => bet.createdTime),
     endTime,
@@ -167,7 +167,7 @@ const computeProbsByOutcome = (
 ) => {
   const { totalBets } = contract
 
-  const betsByOutcome = _.groupBy(bets, (bet) => bet.outcome)
+  const betsByOutcome = groupBy(bets, (bet) => bet.outcome)
   const outcomes = Object.keys(betsByOutcome).filter((outcome) => {
     const maxProb = Math.max(
       ...betsByOutcome[outcome].map((bet) => bet.probAfter)
@@ -175,15 +175,15 @@ const computeProbsByOutcome = (
     return outcome !== '0' && maxProb > 0.02 && totalBets[outcome] > 0.000000001
   })
 
-  const trackedOutcomes = _.sortBy(
+  const trackedOutcomes = sortBy(
     outcomes,
     (outcome) => -1 * getOutcomeProbability(contract, outcome)
   ).slice(0, NUM_LINES)
 
-  const probsByOutcome = _.fromPairs(
+  const probsByOutcome = Object.fromEntries(
     trackedOutcomes.map((outcome) => [outcome, [] as number[]])
   )
-  const sharesByOutcome = _.fromPairs(
+  const sharesByOutcome = Object.fromEntries(
     Object.keys(betsByOutcome).map((outcome) => [outcome, 0])
   )
 
@@ -191,7 +191,7 @@ const computeProbsByOutcome = (
     const { outcome, shares } = bet
     sharesByOutcome[outcome] += shares
 
-    const sharesSquared = _.sumBy(
+    const sharesSquared = sumBy(
       Object.values(sharesByOutcome).map((shares) => shares ** 2)
     )
 

web/components/answers/answers-panel.tsx

@@ -1,5 +1,5 @@
-import _ from 'lodash'
+import { sortBy, partition, sum, uniq } from 'lodash'
-import React, { useLayoutEffect, useState } from 'react'
+import { useLayoutEffect, useState } from 'react'
 
 import { DPM, FreeResponse, FullContract } from 'common/contract'
 import { Col } from '../layout/col'
@@ -32,7 +32,7 @@ export function AnswersPanel(props: {
   const { creatorId, resolution, resolutions, totalBets } = contract
 
   const answers = useAnswers(contract.id) ?? contract.answers
-  const [winningAnswers, losingAnswers] = _.partition(
+  const [winningAnswers, losingAnswers] = partition(
     answers.filter(
       (answer) => answer.id !== '0' && totalBets[answer.id] > 0.000000001
     ),
@@ -40,10 +40,10 @@ export function AnswersPanel(props: {
       answer.id === resolution || (resolutions && resolutions[answer.id])
   )
   const sortedAnswers = [
-    ..._.sortBy(winningAnswers, (answer) =>
+    ...sortBy(winningAnswers, (answer) =>
       resolutions ? -1 * resolutions[answer.id] : 0
     ),
-    ..._.sortBy(
+    ...sortBy(
       resolution ? [] : losingAnswers,
       (answer) => -1 * getDpmOutcomeProbability(contract.totalShares, answer.id)
     ),
@@ -58,7 +58,7 @@ export function AnswersPanel(props: {
     [answerId: string]: number
   }>({})
 
-  const chosenTotal = _.sum(Object.values(chosenAnswers))
+  const chosenTotal = sum(Object.values(chosenAnswers))
 
   const answerItems = getAnswerItems(
     contract,
@@ -158,10 +158,10 @@ function getAnswerItems(
   answers: Answer[],
   user: User | undefined | null
 ) {
-  let outcomes = _.uniq(
+  let outcomes = uniq(answers.map((answer) => answer.number.toString())).filter(
-    answers.map((answer) => answer.number.toString())
+    (outcome) => getOutcomeProbability(contract, outcome) > 0.0001
-  ).filter((outcome) => getOutcomeProbability(contract, outcome) > 0.0001)
+  )
-  outcomes = _.sortBy(outcomes, (outcome) =>
+  outcomes = sortBy(outcomes, (outcome) =>
     getOutcomeProbability(contract, outcome)
   ).reverse()
 

web/components/bet-panel.tsx

@@ -1,6 +1,6 @@
 import clsx from 'clsx'
-import _ from 'lodash'
 import React, { useEffect, useState } from 'react'
+import { partition, sumBy } from 'lodash'
 
 import { useUser } from 'web/hooks/use-user'
 import { Binary, CPMM, DPM, FullContract } from 'common/contract'
@@ -441,13 +441,13 @@ export function SellPanel(props: {
   const resultProb = getCpmmProbability(newPool, contract.p)
 
   const openUserBets = userBets.filter((bet) => !bet.isSold && !bet.sale)
-  const [yesBets, noBets] = _.partition(
+  const [yesBets, noBets] = partition(
     openUserBets,
     (bet) => bet.outcome === 'YES'
   )
   const [yesShares, noShares] = [
-    _.sumBy(yesBets, (bet) => bet.shares),
+    sumBy(yesBets, (bet) => bet.shares),
-    _.sumBy(noBets, (bet) => bet.shares),
+    sumBy(noBets, (bet) => bet.shares),
   ]
 
   const sellOutcome = yesShares ? 'YES' : noShares ? 'NO' : undefined

web/components/bets-list.tsx

@@ -1,5 +1,13 @@
 import Link from 'next/link'
-import _ from 'lodash'
+import {
+  uniq,
+  groupBy,
+  mapValues,
+  sortBy,
+  partition,
+  sumBy,
+  throttle,
+} from 'lodash'
 import dayjs from 'dayjs'
 import { useEffect, useState } from 'react'
 import clsx from 'clsx'
@@ -54,7 +62,7 @@ export function BetsList(props: { user: User }) {
 
   useEffect(() => {
     if (bets) {
-      const contractIds = _.uniq(bets.map((bet) => bet.contractId))
+      const contractIds = uniq(bets.map((bet) => bet.contractId))
 
       let disposed = false
       Promise.all(contractIds.map((id) => getContractFromId(id))).then(
@@ -84,10 +92,10 @@ export function BetsList(props: { user: User }) {
   if (bets.length === 0) return <NoBets />
   // Decending creation time.
   bets.sort((bet1, bet2) => bet2.createdTime - bet1.createdTime)
-  const contractBets = _.groupBy(bets, 'contractId')
+  const contractBets = groupBy(bets, 'contractId')
-  const contractsById = _.fromPairs(contracts.map((c) => [c.id, c]))
+  const contractsById = Object.fromEntries(contracts.map((c) => [c.id, c]))
 
-  const contractsMetrics = _.mapValues(contractBets, (bets, contractId) => {
+  const contractsMetrics = mapValues(contractBets, (bets, contractId) => {
     const contract = contractsById[contractId]
     if (!contract) return getContractBetNullMetrics()
     return getContractBetMetrics(contract, bets)
@@ -110,7 +118,7 @@ export function BetsList(props: { user: User }) {
       (filter === 'open' ? -1 : 1) *
       (c.resolutionTime ?? c.closeTime ?? Infinity),
   }
-  const displayedContracts = _.sortBy(contracts, SORTS[sort])
+  const displayedContracts = sortBy(contracts, SORTS[sort])
     .reverse()
     .filter(FILTERS[filter])
     .filter((c) => {
@@ -121,20 +129,20 @@ export function BetsList(props: { user: User }) {
       return metrics.payout > 0
     })
 
-  const [settled, unsettled] = _.partition(
+  const [settled, unsettled] = partition(
     contracts,
     (c) => c.isResolved || contractsMetrics[c.id].invested === 0
   )
 
-  const currentInvested = _.sumBy(
+  const currentInvested = sumBy(
     unsettled,
     (c) => contractsMetrics[c.id].invested
   )
-  const currentBetsValue = _.sumBy(
+  const currentBetsValue = sumBy(
     unsettled,
     (c) => contractsMetrics[c.id].payout
   )
-  const currentNetInvestment = _.sumBy(
+  const currentNetInvestment = sumBy(
     unsettled,
     (c) => contractsMetrics[c.id].netPayout
   )
@@ -340,10 +348,10 @@ export function MyBetsSummary(props: {
   const excludeSalesAndAntes = bets.filter(
     (b) => !b.isAnte && !b.isSold && !b.sale
   )
-  const yesWinnings = _.sumBy(excludeSalesAndAntes, (bet) =>
+  const yesWinnings = sumBy(excludeSalesAndAntes, (bet) =>
     calculatePayout(contract, bet, 'YES')
   )
-  const noWinnings = _.sumBy(excludeSalesAndAntes, (bet) =>
+  const noWinnings = sumBy(excludeSalesAndAntes, (bet) =>
     calculatePayout(contract, bet, 'NO')
   )
   const { invested, profitPercent, payout, profit } = getContractBetMetrics(
@@ -421,21 +429,19 @@ export function ContractBetsTable(props: {
 
   const bets = props.bets.filter((b) => !b.isAnte)
 
-  const [sales, buys] = _.partition(bets, (bet) => bet.sale)
+  const [sales, buys] = partition(bets, (bet) => bet.sale)
 
-  const salesDict = _.fromPairs(
+  const salesDict = Object.fromEntries(
     sales.map((sale) => [sale.sale?.betId ?? '', sale])
   )
 
-  const [redemptions, normalBets] = _.partition(
+  const [redemptions, normalBets] = partition(
     contract.mechanism === 'cpmm-1' ? bets : buys,
     (b) => b.isRedemption
   )
-  const amountRedeemed = Math.floor(
+  const amountRedeemed = Math.floor(-0.5 * sumBy(redemptions, (b) => b.shares))
-    -0.5 * _.sumBy(redemptions, (b) => b.shares)
-  )
 
-  const amountLoaned = _.sumBy(
+  const amountLoaned = sumBy(
     bets.filter((bet) => !bet.isSold && !bet.sale),
     (bet) => bet.loanAmount ?? 0
   )
@@ -570,10 +576,7 @@ function BetRow(props: { bet: Bet; contract: Contract; saleBet?: Bet }) {
   )
 }
 
-const warmUpSellBet = _.throttle(
+const warmUpSellBet = throttle(() => sellBet({}).catch(() => {}), 5000 /* ms */)
-  () => sellBet({}).catch(() => {}),
-  5000 /* ms */
-)
 
 function SellButton(props: { contract: Contract; bet: Bet }) {
   useEffect(() => {

web/components/bucket-input.tsx

@@ -1,4 +1,3 @@
-import _ from 'lodash'
 import { useState } from 'react'
 
 import { NumericContract } from 'common/contract'

web/components/charity/charity-card.tsx

@@ -1,5 +1,5 @@
 import { StarIcon } from '@heroicons/react/solid'
-import _ from 'lodash'
+import { sumBy } from 'lodash'
 import Link from 'next/link'
 import Image from 'next/image'
 import { Charity } from 'common/charity'
@@ -11,7 +11,7 @@ export function CharityCard(props: { charity: Charity }) {
   const { name, slug, photo, preview, id, tags } = props.charity
 
   const txns = useCharityTxns(id)
-  const raised = _.sumBy(txns, (txn) => txn.amount)
+  const raised = sumBy(txns, (txn) => txn.amount)
 
   return (
     <Link href={`/charity/${slug}`} passHref>

web/components/contract/contract-info-dialog.tsx

@@ -1,7 +1,7 @@
 import { DotsHorizontalIcon } from '@heroicons/react/outline'
 import clsx from 'clsx'
 import dayjs from 'dayjs'
-import _ from 'lodash'
+import { uniqBy, sum } from 'lodash'
 import { useState } from 'react'
 import { Bet } from 'common/bet'
 
@@ -26,7 +26,7 @@ export function ContractInfoDialog(props: { contract: Contract; bets: Bet[] }) {
   const formatTime = (dt: number) => dayjs(dt).format('MMM DD, YYYY hh:mm a z')
 
   const { createdTime, closeTime, resolutionTime } = contract
-  const tradersCount = _.uniqBy(bets, 'userId').length
+  const tradersCount = uniqBy(bets, 'userId').length
 
   return (
     <>
@@ -108,7 +108,7 @@ export function ContractInfoDialog(props: { contract: Contract; bets: Bet[] }) {
               {contract.mechanism === 'dpm-2' && (
                 <tr>
                   <td>Pool</td>
-                  <td>{formatMoney(_.sum(Object.values(contract.pool)))}</td>
+                  <td>{formatMoney(sum(Object.values(contract.pool)))}</td>
                 </tr>
               )}
             </tbody>

web/components/contract/numeric-graph.tsx

@@ -1,8 +1,8 @@
 import { DatumValue } from '@nivo/core'
 import { ResponsiveLine } from '@nivo/line'
 import { NUMERIC_GRAPH_COLOR } from 'common/numeric-constants'
-import _ from 'lodash'
 import { memo } from 'react'
+import { range } from 'lodash'
 import { getDpmOutcomeProbabilities } from '../../../common/calculate-dpm'
 import { NumericContract } from '../../../common/contract'
 import { useWindowSize } from '../../hooks/use-window-size'
@@ -16,10 +16,10 @@ export const NumericGraph = memo(function NumericGraph(props: {
 
   const bucketProbs = getDpmOutcomeProbabilities(totalShares)
 
-  const xs = _.range(bucketCount).map(
+  const xs = range(bucketCount).map(
     (i) => min + ((max - min) * i) / bucketCount
   )
-  const probs = _.range(bucketCount).map((i) => bucketProbs[`${i}`] * 100)
+  const probs = range(bucketCount).map((i) => bucketProbs[`${i}`] * 100)
   const points = probs.map((prob, i) => ({ x: xs[i], y: prob }))
   const maxProb = Math.max(...probs)
   const data = [{ id: 'Probability', data: points, color: NUMERIC_GRAPH_COLOR }]

web/components/feed-create.tsx

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { sample } from 'lodash'
 import { SparklesIcon, XIcon } from '@heroicons/react/solid'
 import { Avatar } from './avatar'
 import { useEffect, useRef, useState } from 'react'
@@ -86,9 +86,7 @@ export default function FeedCreate(props: {
   // Take care not to produce a different placeholder on the server and client
   const [defaultPlaceholder, setDefaultPlaceholder] = useState('')
   useEffect(() => {
-    setDefaultPlaceholder(
+    setDefaultPlaceholder(`e.g. ${sample(ENV_CONFIG.newQuestionPlaceholders)}`)
-      `e.g. ${_.sample(ENV_CONFIG.newQuestionPlaceholders)}`
-    )
   }, [])
 
   const placeholder = props.placeholder ?? defaultPlaceholder

web/components/feed/activity-items.ts

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { last, findLastIndex, uniq, sortBy } from 'lodash'
 
 import { Answer } from 'common/answer'
 import { Bet } from 'common/bet'
@@ -200,17 +200,17 @@ function getAnswerGroups(
 ) {
   const { sortByProb, abbreviated, reversed } = options
 
-  let outcomes = _.uniq(bets.map((bet) => bet.outcome)).filter(
+  let outcomes = uniq(bets.map((bet) => bet.outcome)).filter(
     (outcome) => getOutcomeProbability(contract, outcome) > 0.0001
   )
   if (abbreviated) {
-    const lastComment = _.last(comments)
+    const lastComment = last(comments)
     const lastCommentOutcome = bets.find(
       (bet) => bet.id === lastComment?.betId
     )?.outcome
-    const lastBetOutcome = _.last(bets)?.outcome
+    const lastBetOutcome = last(bets)?.outcome
     if (lastCommentOutcome && lastBetOutcome) {
-      outcomes = _.uniq([
+      outcomes = uniq([
         ...outcomes.filter(
           (outcome) =>
             outcome !== lastCommentOutcome && outcome !== lastBetOutcome
@@ -222,13 +222,13 @@ function getAnswerGroups(
     outcomes = outcomes.slice(-2)
   }
   if (sortByProb) {
-    outcomes = _.sortBy(outcomes, (outcome) =>
+    outcomes = sortBy(outcomes, (outcome) =>
       getOutcomeProbability(contract, outcome)
     )
   } else {
     // Sort by recent bet.
-    outcomes = _.sortBy(outcomes, (outcome) =>
+    outcomes = sortBy(outcomes, (outcome) =>
-      _.findLastIndex(bets, (bet) => bet.outcome === outcome)
+      findLastIndex(bets, (bet) => bet.outcome === outcome)
     )
   }
 
@@ -274,10 +274,10 @@ function getAnswerAndCommentInputGroups(
   comments: Comment[],
   user: User | undefined | null
 ) {
-  let outcomes = _.uniq(bets.map((bet) => bet.outcome)).filter(
+  let outcomes = uniq(bets.map((bet) => bet.outcome)).filter(
     (outcome) => getOutcomeProbability(contract, outcome) > 0.0001
   )
-  outcomes = _.sortBy(outcomes, (outcome) =>
+  outcomes = sortBy(outcomes, (outcome) =>
     getOutcomeProbability(contract, outcome)
   )
   const betsByCurrentUser = bets.filter((bet) => bet.userId === user?.id)
@@ -343,7 +343,7 @@ function groupBetsAndComments(
 
   // iterate through the bets and comment activity items and add them to the items in order of comment creation time:
   const unorderedBetsAndComments = [...commentsWithoutBets, ...groupedBets]
-  let sortedBetsAndComments = _.sortBy(unorderedBetsAndComments, (item) => {
+  let sortedBetsAndComments = sortBy(unorderedBetsAndComments, (item) => {
     if (item.type === 'comment') {
       return item.comment.createdTime
     } else if (item.type === 'bet') {

web/components/feed/feed-bets.tsx

@@ -10,7 +10,7 @@ import { formatMoney } from 'common/util/format'
 import { OutcomeLabel } from 'web/components/outcome-label'
 import { RelativeTimestamp } from 'web/components/relative-timestamp'
 import React, { Fragment } from 'react'
-import * as _ from 'lodash'
+import { uniqBy, partition, sumBy, groupBy } from 'lodash'
 import { JoinSpans } from 'web/components/join-spans'
 
 export function FeedBet(props: {
@@ -104,11 +104,11 @@ function BetGroupSpan(props: {
 }) {
   const { contract, bets, outcome } = props
 
-  const numberTraders = _.uniqBy(bets, (b) => b.userId).length
+  const numberTraders = uniqBy(bets, (b) => b.userId).length
 
-  const [buys, sells] = _.partition(bets, (bet) => bet.amount >= 0)
+  const [buys, sells] = partition(bets, (bet) => bet.amount >= 0)
-  const buyTotal = _.sumBy(buys, (b) => b.amount)
+  const buyTotal = sumBy(buys, (b) => b.amount)
-  const sellTotal = _.sumBy(sells, (b) => -b.amount)
+  const sellTotal = sumBy(sells, (b) => -b.amount)
 
   return (
     <span>
@@ -139,7 +139,7 @@ export function FeedBetGroup(props: {
 }) {
   const { contract, bets, hideOutcome } = props
 
-  const betGroups = _.groupBy(bets, (bet) => bet.outcome)
+  const betGroups = groupBy(bets, (bet) => bet.outcome)
   const outcomes = Object.keys(betGroups)
 
   // Use the time of the last bet for the entire group

web/components/feed/feed-comments.tsx

@@ -3,6 +3,7 @@ import { Comment } from 'common/comment'
 import { User } from 'common/user'
 import { Contract } from 'common/contract'
 import React, { useEffect, useState } from 'react'
+import { minBy, maxBy, groupBy, partition, sumBy } from 'lodash'
 import { useUser } from 'web/hooks/use-user'
 import { formatMoney } from 'common/util/format'
 import { useRouter } from 'next/router'
@@ -16,7 +17,6 @@ import { contractPath } from 'web/lib/firebase/contracts'
 import { firebaseLogin } from 'web/lib/firebase/users'
 import { createComment, MAX_COMMENT_LENGTH } from 'web/lib/firebase/comments'
 import Textarea from 'react-expanding-textarea'
-import * as _ from 'lodash'
 import { Linkify } from 'web/components/linkify'
 import { SiteLink } from 'web/components/site-link'
 import { BetStatusText } from 'web/components/feed/feed-bets'
@@ -36,7 +36,7 @@ export function FeedCommentThread(props: {
     props
   const [showReply, setShowReply] = useState(false)
   const [replyToUsername, setReplyToUsername] = useState('')
-  const betsByUserId = _.groupBy(bets, (bet) => bet.userId)
+  const betsByUserId = groupBy(bets, (bet) => bet.userId)
   const user = useUser()
   const commentsList = comments.filter(
     (comment) =>
@@ -67,7 +67,7 @@ export function FeedCommentThread(props: {
             onReplyClick={scrollAndOpenReplyInput}
             probAtCreatedTime={
               contract.outcomeType === 'BINARY'
-                ? _.minBy(bets, (bet) => {
+                ? minBy(bets, (bet) => {
                     return bet.createdTime < comment.createdTime
                       ? comment.createdTime - bet.createdTime
                       : comment.createdTime
@@ -494,8 +494,7 @@ function getBettorsLargestPositionBeforeTime(
       }
     }
     const majorityAnswer =
-      _.maxBy(Object.keys(answerCounts), (outcome) => answerCounts[outcome]) ??
+      maxBy(Object.keys(answerCounts), (outcome) => answerCounts[outcome]) ?? ''
-      ''
     return {
       userPosition: answerCounts[majorityAnswer] || 0,
       outcome: majorityAnswer,
@@ -505,12 +504,12 @@ function getBettorsLargestPositionBeforeTime(
     return emptyReturn
   }
 
-  const [yesBets, noBets] = _.partition(
+  const [yesBets, noBets] = partition(
     previousBets ?? [],
     (bet) => bet.outcome === 'YES'
   )
-  yesShares = _.sumBy(yesBets, (bet) => bet.shares)
+  yesShares = sumBy(yesBets, (bet) => bet.shares)
-  noShares = _.sumBy(noBets, (bet) => bet.shares)
+  noShares = sumBy(noBets, (bet) => bet.shares)
   yesFloorShares = Math.floor(yesShares)
   noFloorShares = Math.floor(noShares)
 

web/components/feed/feed-items.tsx

@@ -1,6 +1,5 @@
 // From https://tailwindui.com/components/application-ui/lists/feeds
 import React, { useState } from 'react'
-import * as _ from 'lodash'
 import {
   BanIcon,
   CheckIcon,

web/components/feed/find-active-contracts.ts

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { groupBy, mapValues, maxBy, sortBy } from 'lodash'
 import { Contract } from 'web/lib/firebase/contracts'
 import { Comment } from 'web/lib/firebase/comments'
 import { Bet } from 'common/bet'
@@ -44,10 +44,10 @@ export function findActiveContracts(
   }
 
   // Add contracts by last bet time.
-  const contractBets = _.groupBy(recentBets, (bet) => bet.contractId)
+  const contractBets = groupBy(recentBets, (bet) => bet.contractId)
-  const contractMostRecentBet = _.mapValues(
+  const contractMostRecentBet = mapValues(
     contractBets,
-    (bets) => _.maxBy(bets, (bet) => bet.createdTime) as Bet
+    (bets) => maxBy(bets, (bet) => bet.createdTime) as Bet
   )
   for (const bet of Object.values(contractMostRecentBet)) {
     const contract = contractsById.get(bet.contractId)
@@ -60,21 +60,21 @@ export function findActiveContracts(
       !contract.isResolved &&
       (contract.closeTime ?? Infinity) > Date.now()
   )
-  activeContracts = _.sortBy(
+  activeContracts = sortBy(
     activeContracts,
     (c) => -(idToActivityTime.get(c.id) ?? 0)
   )
 
-  const contractComments = _.groupBy(
+  const contractComments = groupBy(
     recentComments,
     (comment) => comment.contractId
   )
-  const contractMostRecentComment = _.mapValues(
+  const contractMostRecentComment = mapValues(
     contractComments,
-    (comments) => _.maxBy(comments, (c) => c.createdTime) as Comment
+    (comments) => maxBy(comments, (c) => c.createdTime) as Comment
   )
 
-  const prioritizedContracts = _.sortBy(activeContracts, (c) => {
+  const prioritizedContracts = sortBy(activeContracts, (c) => {
     const seenTime = seenContracts[c.id]
     if (!seenTime) {
       return 0

web/components/folds/edit-fold-button.tsx

@@ -1,5 +1,5 @@
 import { useState } from 'react'
-import _ from 'lodash'
+import { isEqual } from 'lodash'
 import clsx from 'clsx'
 import { PencilIcon } from '@heroicons/react/outline'
 
@@ -29,7 +29,7 @@ export function EditFoldButton(props: { fold: Fold; className?: string }) {
 
   const saveDisabled =
     name === fold.name &&
-    _.isEqual(tags, fold.tags) &&
+    isEqual(tags, fold.tags) &&
     about === (fold.about ?? '')
 
   const onSubmit = async () => {

web/components/nav/sidebar.tsx

@@ -11,7 +11,7 @@ import {
   SparklesIcon,
 } from '@heroicons/react/outline'
 import clsx from 'clsx'
-import _ from 'lodash'
+import { sortBy } from 'lodash'
 import Link from 'next/link'
 import { useRouter } from 'next/router'
 import { useFollowedFolds } from 'web/hooks/use-fold'
@@ -124,7 +124,7 @@ export default function Sidebar(props: { className?: string }) {
 
   const user = useUser()
   let folds = useFollowedFolds(user) || []
-  folds = _.sortBy(folds, 'followCount').reverse()
+  folds = sortBy(folds, 'followCount').reverse()
   const deservesDailyFreeMarket = !useHasCreatedContractToday(user)
 
   const navigationOptions =

web/components/number-input.tsx

@@ -1,5 +1,4 @@
 import clsx from 'clsx'
-import _ from 'lodash'
 
 import { Col } from './layout/col'
 import { Spacer } from './layout/spacer'

web/components/use-save-shares.ts

@@ -1,7 +1,7 @@
 import { Binary, CPMM, DPM, FullContract } from 'common/contract'
 import { Bet } from 'common/bet'
 import { useEffect, useState } from 'react'
-import _ from 'lodash'
+import { partition, sumBy } from 'lodash'
 
 export const useSaveShares = (
   contract: FullContract<CPMM | DPM, Binary>,
@@ -17,13 +17,13 @@ export const useSaveShares = (
     | undefined
   >()
 
-  const [yesBets, noBets] = _.partition(
+  const [yesBets, noBets] = partition(
     userBets ?? [],
     (bet) => bet.outcome === 'YES'
   )
   const [yesShares, noShares] = [
-    _.sumBy(yesBets, (bet) => bet.shares),
+    sumBy(yesBets, (bet) => bet.shares),
-    _.sumBy(noBets, (bet) => bet.shares),
+    sumBy(noBets, (bet) => bet.shares),
   ]
 
   const yesFloorShares = Math.round(yesShares) === 0 ? 0 : Math.floor(yesShares)

web/components/user-page.tsx

@@ -19,10 +19,10 @@ import { Comment, getUsersComments } from 'web/lib/firebase/comments'
 import { Contract } from 'common/contract'
 import { getContractFromId, listContracts } from 'web/lib/firebase/contracts'
 import { LoadingIndicator } from './loading-indicator'
-import _ from 'lodash'
 import { BetsList } from './bets-list'
 import { Bet } from 'common/bet'
 import { getUserBets } from 'web/lib/firebase/bets'
+import { uniq } from 'lodash'
 
 export function UserLink(props: {
   name: string
@@ -70,7 +70,7 @@ export function UserPage(props: {
   }, [user])
 
   useEffect(() => {
-    const uniqueContractIds = _.uniq(
+    const uniqueContractIds = uniq(
       usersComments.map((comment) => comment.contractId)
     )
     Promise.all(

web/hooks/use-algo-feed.ts

@@ -1,4 +1,3 @@
-import _, { Dictionary } from 'lodash'
 import { useState, useEffect } from 'react'
 import type { feed } from 'common/feed'
 import { useTimeSinceFirstRender } from './use-time-since-first-render'
@@ -15,7 +14,7 @@ export const useAlgoFeed = (
   category: string
 ) => {
   const [allFeed, setAllFeed] = useState<feed>()
-  const [categoryFeeds, setCategoryFeeds] = useState<Dictionary<feed>>()
+  const [categoryFeeds, setCategoryFeeds] = useState<{ [x: string]: feed }>()
 
   const getTime = useTimeSinceFirstRender()
 

web/hooks/use-contracts.ts

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { isEqual } from 'lodash'
 import { useEffect, useRef, useState } from 'react'
 import {
   Contract,
@@ -80,14 +80,14 @@ export const useUpdatedContracts = (contracts: Contract[] | undefined) => {
   useEffect(() => {
     if (contracts === undefined) return
 
-    contractDict.current = _.fromPairs(contracts.map((c) => [c.id, c]))
+    contractDict.current = Object.fromEntries(contracts.map((c) => [c.id, c]))
 
     const disposes = contracts.map((contract) => {
       const { id } = contract
 
       return listenForContract(id, (contract) => {
         const curr = contractDict.current[id]
-        if (!_.isEqual(curr, contract)) {
+        if (!isEqual(curr, contract)) {
           contractDict.current[id] = contract as Contract
           triggerUpdate((n) => n + 1)
         }

web/hooks/use-fold.ts

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { isEqual, sortBy } from 'lodash'
 import { useEffect, useState } from 'react'
 import { Fold } from 'common/fold'
 import { User } from 'common/user'
@@ -95,9 +95,9 @@ export const useFollowedFolds = (user: User | null | undefined) => {
         setFollowedFolds(JSON.parse(followedFoldJson))
         // Exit early if ids and followedFoldIds have all the same elements.
         if (
-          _.isEqual(
+          isEqual(
-            _.sortBy(ids),
+            sortBy(ids),
-            _.sortBy(JSON.parse(followedFoldJson).map((f: Fold) => f.id))
+            sortBy(JSON.parse(followedFoldJson).map((f: Fold) => f.id))
           )
         ) {
           return

web/hooks/use-measure-size.ts

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { debounce } from 'lodash'
 import { RefObject, useMemo, useLayoutEffect, useRef, useState } from 'react'
 
 type elem_size =
@@ -21,7 +21,7 @@ export function useListenElemSize<T extends HTMLElement>(
     }
 
     return debounceMs
-      ? _.debounce(updateSize, debounceMs, { leading: false, trailing: true })
+      ? debounce(updateSize, debounceMs, { leading: false, trailing: true })
       : updateSize
   }, [callback, elemRef, debounceMs])
 

web/hooks/use-propz.ts

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { isEmpty } from 'lodash'
 import { useRouter } from 'next/router'
 import { useState, useEffect } from 'react'
 import { IS_PRIVATE_MANIFOLD } from 'common/envs/constants'
@@ -16,7 +16,7 @@ export function usePropz(
   getStaticPropz: (props: PropzProps) => Promise<any>
 ) {
   // If props were successfully server-side generated, just use those
-  if (!_.isEmpty(initialProps)) {
+  if (!isEmpty(initialProps)) {
     return initialProps
   }
 

web/hooks/use-seen-contracts.ts

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { mapValues } from 'lodash'
 import { useEffect, useState } from 'react'
 import { Contract } from 'common/contract'
 import { trackView } from 'web/lib/firebase/tracking'
@@ -38,7 +38,7 @@ export const useSaveSeenContract = (
 const key = 'feed-seen-contracts'
 
 const getSeenContracts = () => {
-  return _.mapValues(
+  return mapValues(
     JSON.parse(localStorage.getItem(key) ?? '{}'),
     (time) => +time
   )

web/hooks/use-sort-and-query-params.tsx

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { defaults, debounce } from 'lodash'
 import { useRouter } from 'next/router'
 import { useEffect, useMemo, useState } from 'react'
 import { useSearchBox } from 'react-instantsearch-hooks-web'
@@ -18,7 +18,7 @@ export function useInitialQueryAndSort(options?: {
   defaultSort: Sort
   shouldLoadFromStorage?: boolean
 }) {
-  const { defaultSort, shouldLoadFromStorage } = _.defaults(options, {
+  const { defaultSort, shouldLoadFromStorage } = defaults(options, {
     defaultSort: '24-hour-vol',
     shouldLoadFromStorage: true,
   })
@@ -79,7 +79,7 @@ export function useUpdateQueryAndSort(props: {
   // Debounce router query update.
   const pushQuery = useMemo(
     () =>
-      _.debounce((query: string | undefined) => {
+      debounce((query: string | undefined) => {
         if (query) {
           router.query.q = query
         } else {

web/hooks/use-state-check-equality.ts

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { isEqual } from 'lodash'
 import { useMemo, useRef, useState } from 'react'
 
 export const useStateCheckEquality = <T>(initialState: T) => {
@@ -10,7 +10,7 @@ export const useStateCheckEquality = <T>(initialState: T) => {
   const checkSetState = useMemo(
     () => (newState: T) => {
       const state = stateRef.current
-      if (!_.isEqual(state, newState)) {
+      if (!isEqual(state, newState)) {
         setState(newState)
       }
     },

web/hooks/use-user-bets.ts

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { uniq } from 'lodash'
 import { useEffect, useState } from 'react'
 import {
   Bet,
@@ -51,7 +51,7 @@ export const useUserBetContracts = (
       return listenForUserBets(
         userId,
         (bets) => {
-          const contractIds = _.uniq(bets.map((bet) => bet.contractId))
+          const contractIds = uniq(bets.map((bet) => bet.contractId))
           setContractIds(contractIds)
           localStorage.setItem(key, JSON.stringify(contractIds))
         },

web/hooks/use-user.ts

@@ -1,4 +1,3 @@
-import _ from 'lodash'
 import { useEffect, useState } from 'react'
 import { PrivateUser } from 'common/user'
 import {

web/lib/firebase/bets.ts

@@ -5,7 +5,7 @@ import {
   where,
   orderBy,
 } from 'firebase/firestore'
-import _ from 'lodash'
+import { range } from 'lodash'
 
 import { db } from './init'
 import { Bet } from 'common/bet'
@@ -138,7 +138,7 @@ export async function getDailyBets(startTime: number, numberOfDays: number) {
   const query = getBetsQuery(startTime, startTime + DAY_IN_MS * numberOfDays)
   const bets = await getValues<Bet>(query)
 
-  const betsByDay = _.range(0, numberOfDays).map(() => [] as Bet[])
+  const betsByDay = range(0, numberOfDays).map(() => [] as Bet[])
   for (const bet of bets) {
     const dayIndex = Math.floor((bet.createdTime - startTime) / DAY_IN_MS)
     betsByDay[dayIndex].push(bet)

web/lib/firebase/comments.ts

@@ -7,7 +7,7 @@ import {
   setDoc,
   where,
 } from 'firebase/firestore'
-import _ from 'lodash'
+import { range } from 'lodash'
 
 import { getValues, listenForValues } from './utils'
 import { db } from './init'
@@ -117,7 +117,7 @@ export async function getDailyComments(
   )
   const comments = await getValues<Comment>(query)
 
-  const commentsByDay = _.range(0, numberOfDays).map(() => [] as Comment[])
+  const commentsByDay = range(0, numberOfDays).map(() => [] as Comment[])
   for (const comment of comments) {
     const dayIndex = Math.floor((comment.createdTime - startTime) / DAY_IN_MS)
     commentsByDay[dayIndex].push(comment)

web/lib/firebase/contracts.ts

@@ -13,7 +13,7 @@ import {
   updateDoc,
   limit,
 } from 'firebase/firestore'
-import _ from 'lodash'
+import { range, sortBy } from 'lodash'
 
 import { app } from './init'
 import { getValues, listenForValue, listenForValues } from './utils'
@@ -225,7 +225,7 @@ export function listenForHotContracts(
   setHotContracts: (contracts: Contract[]) => void
 ) {
   return listenForValues<Contract>(hotContractsQuery, (contracts) => {
-    const hotContracts = _.sortBy(
+    const hotContracts = sortBy(
       chooseRandomSubset(contracts, 4),
       (contract) => contract.volume24Hours
     )
@@ -235,7 +235,7 @@ export function listenForHotContracts(
 
 export async function getHotContracts() {
   const contracts = await getValues<Contract>(hotContractsQuery)
-  return _.sortBy(
+  return sortBy(
     chooseRandomSubset(contracts, 10),
     (contract) => -1 * contract.volume24Hours
   )
@@ -245,7 +245,7 @@ export async function getContractsBySlugs(slugs: string[]) {
   const q = query(contractCollection, where('slug', 'in', slugs))
   const snapshot = await getDocs(q)
   const contracts = snapshot.docs.map((doc) => doc.data() as Contract)
-  return _.sortBy(contracts, (contract) => -1 * contract.volume24Hours)
+  return sortBy(contracts, (contract) => -1 * contract.volume24Hours)
 }
 
 const topWeeklyQuery = query(
@@ -269,7 +269,7 @@ const closingSoonQuery = query(
 
 export async function getClosingSoonContracts() {
   const contracts = await getValues<Contract>(closingSoonQuery)
-  return _.sortBy(
+  return sortBy(
     chooseRandomSubset(contracts, 2),
     (contract) => contract.closeTime
   )
@@ -295,7 +295,7 @@ export async function getDailyContracts(
   )
   const contracts = await getValues<Contract>(query)
 
-  const contractsByDay = _.range(0, numberOfDays).map(() => [] as Contract[])
+  const contractsByDay = range(0, numberOfDays).map(() => [] as Contract[])
   for (const contract of contracts) {
     const dayIndex = Math.floor((contract.createdTime - startTime) / DAY_IN_MS)
     contractsByDay[dayIndex].push(contract)

web/lib/firebase/folds.ts

@@ -10,7 +10,7 @@ import {
   updateDoc,
   where,
 } from 'firebase/firestore'
-import _ from 'lodash'
+import { sortBy } from 'lodash'
 import { Fold } from 'common/fold'
 import { Contract, contractCollection } from './contracts'
 import { db } from './init'
@@ -171,7 +171,7 @@ export async function getFoldsByTags(tags: string[]) {
     )
   )
 
-  return _.sortBy(folds, (fold) => -1 * fold.followCount)
+  return sortBy(folds, (fold) => -1 * fold.followCount)
 }
 
 export function listenForFoldsWithTags(
@@ -187,7 +187,7 @@ export function listenForFoldsWithTags(
   )
 
   return listenForValues<Fold>(q, (folds) => {
-    const sorted = _.sortBy(folds, (fold) => -1 * fold.followCount)
+    const sorted = sortBy(folds, (fold) => -1 * fold.followCount)
     setFolds(sorted)
   })
 }

web/lib/firebase/users.ts

@@ -18,7 +18,7 @@ import {
   GoogleAuthProvider,
   signInWithPopup,
 } from 'firebase/auth'
-import _ from 'lodash'
+import { range, throttle, zip } from 'lodash'
 
 import { app } from './init'
 import { PrivateUser, User } from 'common/user'
@@ -83,7 +83,7 @@ const CACHED_USER_KEY = 'CACHED_USER_KEY'
 // used to avoid weird race condition
 let createUserPromise: Promise<User | null> | undefined = undefined
 
-const warmUpCreateUser = _.throttle(createUser, 5000 /* ms */)
+const warmUpCreateUser = throttle(createUser, 5000 /* ms */)
 
 export function listenForLogin(onUser: (user: User | null) => void) {
   const cachedUser = localStorage.getItem(CACHED_USER_KEY)
@@ -210,7 +210,7 @@ export async function getDailyNewUsers(
   const query = getUsersQuery(startTime, startTime + DAY_MS * numberOfDays)
   const users = await getValues<User>(query)
 
-  const usersByDay = _.range(0, numberOfDays).map(() => [] as User[])
+  const usersByDay = range(0, numberOfDays).map(() => [] as User[])
   for (const user of users) {
     const dayIndex = Math.floor((user.createdTime - startTime) / DAY_MS)
     usersByDay[dayIndex].push(user)
@@ -235,5 +235,5 @@ export async function getCategoryFeeds(userId: string) {
     )
   )
   const feeds = feedData.map((data) => data?.feed ?? [])
-  return _.fromPairs(_.zip(CATEGORY_LIST, feeds) as [string, feed][])
+  return Object.fromEntries(zip(CATEGORY_LIST, feeds) as [string, feed][])
 }

web/next.config.js

@@ -6,6 +6,11 @@ module.exports = {
   experimental: {
     externalDir: true,
     optimizeCss: true,
+    modularizeImports: {
+      lodash: {
+        transform: 'lodash/{{member}}',
+      },
+    },
   },
   images: {
     domains: ['lh3.googleusercontent.com', 'i.imgur.com'],

web/pages/[username]/[contractSlug].tsx

@@ -1,6 +1,6 @@
 import React, { useEffect, useMemo, useState } from 'react'
 import { ArrowLeftIcon } from '@heroicons/react/outline'
-import _ from 'lodash'
+import { keyBy, sortBy, groupBy, sumBy, mapValues } from 'lodash'
 
 import { useContractWithPreload } from 'web/hooks/use-contract'
 import { ContractOverview } from 'web/components/contract/contract-overview'
@@ -250,13 +250,13 @@ function ContractLeaderboard(props: { contract: Contract; bets: Bet[] }) {
 
   const { userProfits, top5Ids } = useMemo(() => {
     // Create a map of userIds to total profits (including sales)
-    const betsByUser = _.groupBy(bets, 'userId')
+    const betsByUser = groupBy(bets, 'userId')
-    const userProfits = _.mapValues(betsByUser, (bets) =>
+    const userProfits = mapValues(betsByUser, (bets) =>
-      _.sumBy(bets, (bet) => resolvedPayout(contract, bet) - bet.amount)
+      sumBy(bets, (bet) => resolvedPayout(contract, bet) - bet.amount)
     )
     // Find the 5 users with the most profits
-    const top5Ids = _.entries(userProfits)
+    const top5Ids = Object.entries(userProfits)
-      .sort(([i1, p1], [i2, p2]) => p2 - p1)
+      .sort(([_i1, p1], [_i2, p2]) => p2 - p1)
       .filter(([, p]) => p > 0)
       .slice(0, 5)
       .map(([id]) => id)
@@ -267,7 +267,7 @@ function ContractLeaderboard(props: { contract: Contract; bets: Bet[] }) {
     console.log('foo')
     if (top5Ids.length > 0) {
       listUsers(top5Ids).then((users) => {
-        const sortedUsers = _.sortBy(users, (user) => -userProfits[user.id])
+        const sortedUsers = sortBy(users, (user) => -userProfits[user.id])
         setUsers(sortedUsers)
       })
     }
@@ -294,8 +294,8 @@ function ContractTopTrades(props: {
   comments: Comment[]
 }) {
   const { contract, bets, comments } = props
-  const commentsById = _.keyBy(comments, 'id')
+  const commentsById = keyBy(comments, 'id')
-  const betsById = _.keyBy(bets, 'id')
+  const betsById = keyBy(bets, 'id')
 
   // If 'id2' is the sale of 'id1', both are logged with (id2 - id1) of profit
   // Otherwise, we record the profit at resolution time
@@ -312,11 +312,11 @@ function ContractTopTrades(props: {
   }
 
   // Now find the betId with the highest profit
-  const topBetId = _.sortBy(bets, (b) => -profitById[b.id])[0]?.id
+  const topBetId = sortBy(bets, (b) => -profitById[b.id])[0]?.id
   const topBettor = useUserById(betsById[topBetId]?.userId)
 
   // And also the commentId of the comment with the highest profit
-  const topCommentId = _.sortBy(
+  const topCommentId = sortBy(
     comments,
     (c) => c.betId && -profitById[c.betId]
   )[0]?.id

web/pages/admin.tsx

@@ -6,7 +6,7 @@ import dayjs from 'dayjs'
 import { usePrivateUsers, useUsers } from 'web/hooks/use-users'
 import Custom404 from './404'
 import { useContracts } from 'web/hooks/use-contracts'
-import _ from 'lodash'
+import { mapKeys } from 'lodash'
 import { useAdmin } from 'web/hooks/use-admin'
 import { contractPath } from 'web/lib/firebase/contracts'
 
@@ -23,7 +23,7 @@ function UsersTable() {
   let privateUsers = usePrivateUsers()
 
   // Map private users by user id
-  const privateUsersById = _.mapKeys(privateUsers, 'id')
+  const privateUsersById = mapKeys(privateUsers, 'id')
   console.log('private users by id', privateUsersById)
 
   // For each user, set their email from the PrivateUser

web/pages/analytics.tsx

@@ -1,5 +1,5 @@
 import dayjs from 'dayjs'
-import _ from 'lodash'
+import { zip, uniq, sumBy } from 'lodash'
 import { IS_PRIVATE_MANIFOLD } from 'common/envs/constants'
 import {
   DailyCountChart,
@@ -40,12 +40,12 @@ export async function getStaticPropz() {
   )
   const dailyCommentCounts = dailyComments.map((comments) => comments.length)
 
-  const dailyUserIds = _.zip(dailyContracts, dailyBets, dailyComments).map(
+  const dailyUserIds = zip(dailyContracts, dailyBets, dailyComments).map(
     ([contracts, bets, comments]) => {
       const creatorIds = (contracts ?? []).map((c) => c.creatorId)
       const betUserIds = (bets ?? []).map((bet) => bet.userId)
       const commentUserIds = (comments ?? []).map((comment) => comment.userId)
-      return _.uniq([...creatorIds, ...betUserIds, ...commentUserIds])
+      return uniq([...creatorIds, ...betUserIds, ...commentUserIds])
     }
   )
 
@@ -87,7 +87,7 @@ export async function getStaticPropz() {
     for (let j = lastWeek.start; j <= lastWeek.end; j++) {
       dailyUserIds[j].forEach((userId) => activeLastWeek.add(userId))
     }
-    const retainedCount = _.sumBy(Array.from(activeTwoWeeksAgo), (userId) =>
+    const retainedCount = sumBy(Array.from(activeTwoWeeksAgo), (userId) =>
       activeLastWeek.has(userId) ? 1 : 0
     )
     const retainedFrac = retainedCount / activeTwoWeeksAgo.size
@@ -112,7 +112,7 @@ export async function getStaticPropz() {
     for (let j = lastMonth.start; j <= lastMonth.end; j++) {
       dailyUserIds[j].forEach((userId) => activeLastMonth.add(userId))
     }
-    const retainedCount = _.sumBy(Array.from(activeTwoMonthsAgo), (userId) =>
+    const retainedCount = sumBy(Array.from(activeTwoMonthsAgo), (userId) =>
       activeLastMonth.has(userId) ? 1 : 0
     )
     const retainedFrac = retainedCount / activeTwoMonthsAgo.size

web/pages/charity/[charitySlug].tsx

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { sortBy, sumBy, uniqBy } from 'lodash'
 import clsx from 'clsx'
 import { useEffect, useRef, useState } from 'react'
 import { Col } from 'web/components/layout/col'
@@ -41,13 +41,13 @@ function CharityPage(props: { charity: Charity }) {
   const user = useUser()
 
   const txns = useCharityTxns(charity.id)
-  const newToOld = _.sortBy(txns, (txn) => -txn.createdTime)
+  const newToOld = sortBy(txns, (txn) => -txn.createdTime)
-  const totalRaised = _.sumBy(txns, (txn) => txn.amount)
+  const totalRaised = sumBy(txns, (txn) => txn.amount)
-  const fromYou = _.sumBy(
+  const fromYou = sumBy(
     txns.filter((txn) => txn.fromId === user?.id),
     (txn) => txn.amount
   )
-  const numSupporters = _.uniqBy(txns, (txn) => txn.fromId).length
+  const numSupporters = uniqBy(txns, (txn) => txn.fromId).length
 
   const { width, height } = useWindowSize()
   const [showConfetti, setShowConfetti] = useState(false)

web/pages/charity/index.tsx

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { mapValues, groupBy, sumBy, sum, sortBy, debounce } from 'lodash'
 import { useState, useMemo } from 'react'
 import { charities, Charity as CharityType } from 'common/charity'
 import { CharityCard } from 'web/components/charity/charity-card'
@@ -12,11 +12,11 @@ import { formatMoney } from 'common/util/format'
 
 export async function getStaticProps() {
   const txns = await getAllCharityTxns()
-  const totals = _.mapValues(_.groupBy(txns, 'toId'), (txns) =>
+  const totals = mapValues(groupBy(txns, 'toId'), (txns) =>
-    _.sumBy(txns, (txn) => txn.amount)
+    sumBy(txns, (txn) => txn.amount)
   )
-  const totalRaised = _.sum(Object.values(totals))
+  const totalRaised = sum(Object.values(totals))
-  const sortedCharities = _.sortBy(charities, [
+  const sortedCharities = sortBy(charities, [
     (charity) => (charity.tags?.includes('Featured') ? 0 : 1),
     (charity) => -totals[charity.id],
   ])
@@ -37,7 +37,7 @@ export default function Charity(props: {
   const { totalRaised, charities } = props
 
   const [query, setQuery] = useState('')
-  const debouncedQuery = _.debounce(setQuery, 50)
+  const debouncedQuery = debounce(setQuery, 50)
 
   const filterCharities = useMemo(
     () =>

web/pages/fold/[...slugs]/index.tsx

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { flatten, take, partition, sortBy } from 'lodash'
 
 import { Fold } from 'common/fold'
 import { Comment } from 'common/comment'
@@ -47,8 +47,8 @@ export async function getStaticPropz(props: { params: { slugs: string[] } }) {
     contracts.map((contract) => listAllBets(contract.id))
   )
 
-  let activeContracts = findActiveContracts(contracts, [], _.flatten(bets), {})
+  let activeContracts = findActiveContracts(contracts, [], flatten(bets), {})
-  const [resolved, unresolved] = _.partition(
+  const [resolved, unresolved] = partition(
     activeContracts,
     ({ isResolved }) => isResolved
   )
@@ -80,8 +80,8 @@ export async function getStaticPropz(props: { params: { slugs: string[] } }) {
 }
 
 async function toTopUsers(userScores: { [userId: string]: number }) {
-  const topUserPairs = _.take(
+  const topUserPairs = take(
-    _.sortBy(Object.entries(userScores), ([_, score]) => -1 * score),
+    sortBy(Object.entries(userScores), ([_, score]) => -1 * score),
     10
   ).filter(([_, score]) => score >= 0.5)
 
@@ -134,7 +134,7 @@ export default function FoldPage(props: {
   const isCurator = user && fold && user.id === fold.curatorId
 
   const taggedContracts = useTaggedContracts(fold?.tags) ?? props.contracts
-  const contractsMap = _.fromPairs(
+  const contractsMap = Object.fromEntries(
     taggedContracts.map((contract) => [contract.id, contract])
   )
 

web/pages/folds.tsx

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { sortBy, debounce } from 'lodash'
 import Link from 'next/link'
 import { useEffect, useState } from 'react'
 import { Fold } from 'common/fold'
@@ -21,7 +21,7 @@ export async function getStaticProps() {
   const curators = await Promise.all(
     folds.map((fold) => getUser(fold.curatorId))
   )
-  const curatorsDict = _.fromPairs(
+  const curatorsDict = Object.fromEntries(
     curators.map((curator) => [curator.id, curator])
   )
 
@@ -37,7 +37,7 @@ export async function getStaticProps() {
 
 export default function Folds(props: {
   folds: Fold[]
-  curatorsDict: _.Dictionary<User>
+  curatorsDict: { [k: string]: User }
 }) {
   const [curatorsDict, setCuratorsDict] = useState(props.curatorsDict)
 
@@ -51,7 +51,7 @@ export default function Folds(props: {
     if (newFolds.length > 0) {
       Promise.all(newFolds.map(({ curatorId }) => getUser(curatorId))).then(
         (newUsers) => {
-          const newUsersDict = _.fromPairs(
+          const newUsersDict = Object.fromEntries(
             newUsers.map((user) => [user.id, user])
           )
           setCuratorsDict({ ...curatorsDict, ...newUsersDict })
@@ -68,7 +68,7 @@ export default function Folds(props: {
   }
 
   // List followed folds first, then folds with the highest follower count
-  const matches = _.sortBy(folds, [
+  const matches = sortBy(folds, [
     (fold) => !followedFoldIds.includes(fold.id),
     (fold) => -1 * fold.followCount,
   ]).filter(
@@ -79,7 +79,7 @@ export default function Folds(props: {
       check(f.lowercaseTags.map((tag) => `#${tag}`).join(' '))
   )
   // Not strictly necessary, but makes the "hold delete" experience less laggy
-  const debouncedQuery = _.debounce(setQuery, 50)
+  const debouncedQuery = debounce(setQuery, 50)
 
   return (
     <Page>

web/pages/server-sitemap.xml.tsx

@@ -1,4 +1,4 @@
-import _ from 'lodash'
+import { sortBy } from 'lodash'
 import { GetServerSideProps } from 'next'
 import { getServerSideSitemap, ISitemapField } from 'next-sitemap'
 
@@ -10,7 +10,7 @@ export const getServerSideProps: GetServerSideProps = async (ctx) => {
   const response = await fetch(`https://${DOMAIN}/api/v0/markets`)
 
   const liteMarkets = (await response.json()) as LiteMarket[]
-  const sortedMarkets = _.sortBy(liteMarkets, (m) => -m.volume24Hours)
+  const sortedMarkets = sortBy(liteMarkets, (m) => -m.volume24Hours)
 
   const fields = sortedMarkets.map((market) => ({
     // See https://www.sitemaps.org/protocol.html

yarn.lock

@@ -2394,6 +2394,13 @@ eslint-plugin-jsx-a11y@^6.5.1:
     language-tags "^1.0.5"
     minimatch "^3.0.4"
 
+eslint-plugin-lodash@^7.4.0:
+  version "7.4.0"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-lodash/-/eslint-plugin-lodash-7.4.0.tgz#14a761547f126c92ff56789662a20a44f8bb6290"
+  integrity sha512-Tl83UwVXqe1OVeBRKUeWcfg6/pCW1GTRObbdnbEJgYwjxp5Q92MEWQaH9+dmzbRt6kvYU1Mp893E79nJiCSM8A==
+  dependencies:
+    lodash "^4.17.21"
+
 eslint-plugin-react-hooks@^4.5.0:
   version "4.5.0"
   resolved "https://registry.yarnpkg.com/eslint-plugin-react-hooks/-/eslint-plugin-react-hooks-4.5.0.tgz#5f762dfedf8b2cf431c689f533c9d3fa5dcf25ad"