diff --git a/web/.eslintrc.js b/web/.eslintrc.js
index f864ffa2..6c34b521 100644
--- a/web/.eslintrc.js
+++ b/web/.eslintrc.js
@@ -1,10 +1,21 @@
 module.exports = {
   parser: '@typescript-eslint/parser',
   plugins: ['lodash'],
-  extends: ['plugin:react-hooks/recommended', 'plugin:@next/next/recommended'],
+  extends: [
+    'plugin:@typescript-eslint/recommended',
+    'plugin:react-hooks/recommended',
+    'plugin:@next/next/recommended',
+  ],
   rules: {
+    '@typescript-eslint/no-empty-function': 'off',
+    '@typescript-eslint/no-unused-vars': 'off',
+    '@typescript-eslint/no-explicit-any': 'off',
     '@next/next/no-img-element': 'off',
     '@next/next/no-typos': 'off',
     'lodash/import-scope': [2, 'member'],
   },
+  env: {
+    browser: true,
+    node: true,
+  },
 }
diff --git a/web/components/amount-input.tsx b/web/components/amount-input.tsx
index 84a29b6d..a31957cb 100644
--- a/web/components/amount-input.tsx
+++ b/web/components/amount-input.tsx
@@ -1,4 +1,5 @@
 import clsx from 'clsx'
+import React from 'react'
 import { useUser } from 'web/hooks/use-user'
 import { formatMoney } from 'common/util/format'
 import { Col } from './layout/col'
diff --git a/web/components/client-render.tsx b/web/components/client-render.tsx
index a58c90ff..d26d2301 100644
--- a/web/components/client-render.tsx
+++ b/web/components/client-render.tsx
@@ -1,5 +1,5 @@
 // Adapted from https://stackoverflow.com/a/50884055/1222351
-import { useEffect, useState } from 'react'
+import React, { useEffect, useState } from 'react'
 
 export function ClientRender(props: { children: React.ReactNode }) {
   const { children } = props
diff --git a/web/components/contract/quick-bet.tsx b/web/components/contract/quick-bet.tsx
index d7b37834..c4b1ec16 100644
--- a/web/components/contract/quick-bet.tsx
+++ b/web/components/contract/quick-bet.tsx
@@ -229,12 +229,13 @@ function QuickOutcomeView(props: {
     case 'NUMERIC':
       display = formatLargeNumber(getExpectedValue(contract as NumericContract))
       break
-    case 'FREE_RESPONSE':
+    case 'FREE_RESPONSE': {
       const topAnswer = getTopAnswer(contract as FreeResponseContract)
       display =
         topAnswer &&
         formatPercent(getOutcomeProbability(contract, topAnswer.id))
       break
+    }
   }
 
   return (
diff --git a/web/components/datetime-tooltip.tsx b/web/components/datetime-tooltip.tsx
index 69c4521e..7f7a9b45 100644
--- a/web/components/datetime-tooltip.tsx
+++ b/web/components/datetime-tooltip.tsx
@@ -1,3 +1,4 @@
+import React from 'react'
 import dayjs from 'dayjs'
 import utc from 'dayjs/plugin/utc'
 import timezone from 'dayjs/plugin/timezone'
diff --git a/web/components/feed/activity-items.ts b/web/components/feed/activity-items.ts
index c958a892..b8d99598 100644
--- a/web/components/feed/activity-items.ts
+++ b/web/components/feed/activity-items.ts
@@ -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) => {
+  const sortedBetsAndComments = sortBy(unorderedBetsAndComments, (item) => {
     if (item.type === 'comment') {
       return item.comment.createdTime
     } else if (item.type === 'bet') {
@@ -540,7 +540,7 @@ export function getSpecificContractActivityItems(
   }
 ) {
   const { mode } = options
-  let items = [] as ActivityItem[]
+  const items = [] as ActivityItem[]
 
   switch (mode) {
     case 'bets':
@@ -559,7 +559,7 @@ export function getSpecificContractActivityItems(
       )
       break
 
-    case 'comments':
+    case 'comments': {
       const nonFreeResponseComments = comments.filter((comment) =>
         commentIsGeneralComment(comment, contract)
       )
@@ -585,6 +585,7 @@ export function getSpecificContractActivityItems(
         ),
       })
       break
+    }
     case 'free-response-comment-answer-groups':
       items.push(
         ...getAnswerAndCommentInputGroups(
diff --git a/web/components/feed/copy-link-date-time.tsx b/web/components/feed/copy-link-date-time.tsx
index 354996a4..60395801 100644
--- a/web/components/feed/copy-link-date-time.tsx
+++ b/web/components/feed/copy-link-date-time.tsx
@@ -21,7 +21,7 @@ export function CopyLinkDateTimeComponent(props: {
     event: React.MouseEvent<HTMLAnchorElement, MouseEvent>
   ) {
     event.preventDefault()
-    let elementLocation = `https://${ENV_CONFIG.domain}${contractPath(
+    const elementLocation = `https://${ENV_CONFIG.domain}${contractPath(
       contract
     )}#${elementId}`
 
diff --git a/web/components/join-spans.tsx b/web/components/join-spans.tsx
index e6947ee8..c11b4eed 100644
--- a/web/components/join-spans.tsx
+++ b/web/components/join-spans.tsx
@@ -1,6 +1,8 @@
+import { ReactNode } from 'react'
+
 export const JoinSpans = (props: {
   children: any[]
-  separator?: JSX.Element | string
+  separator?: ReactNode
 }) => {
   const { separator } = props
   const children = props.children.filter((x) => !!x)
diff --git a/web/components/layout/modal.tsx b/web/components/layout/modal.tsx
index 6c6b1af4..d61a38dd 100644
--- a/web/components/layout/modal.tsx
+++ b/web/components/layout/modal.tsx
@@ -1,9 +1,9 @@
-import { Fragment } from 'react'
+import { Fragment, ReactNode } from 'react'
 import { Dialog, Transition } from '@headlessui/react'
 
 // From https://tailwindui.com/components/application-ui/overlays/modals
 export function Modal(props: {
-  children: React.ReactNode
+  children: ReactNode
   open: boolean
   setOpen: (open: boolean) => void
 }) {
diff --git a/web/components/layout/tabs.tsx b/web/components/layout/tabs.tsx
index fc9dd775..eeab17f9 100644
--- a/web/components/layout/tabs.tsx
+++ b/web/components/layout/tabs.tsx
@@ -1,12 +1,12 @@
 import clsx from 'clsx'
 import Link from 'next/link'
-import { useState } from 'react'
+import { ReactNode, useState } from 'react'
 import { Row } from './row'
 
 type Tab = {
   title: string
-  tabIcon?: JSX.Element
-  content: JSX.Element
+  tabIcon?: ReactNode
+  content: ReactNode
   // If set, change the url to this href when the tab is selected
   href?: string
 }
diff --git a/web/components/linkify.tsx b/web/components/linkify.tsx
index 3a5f2a18..f33b2bf5 100644
--- a/web/components/linkify.tsx
+++ b/web/components/linkify.tsx
@@ -4,14 +4,14 @@ import { SiteLink } from './site-link'
 // Return a JSX span, linkifying @username, #hashtags, and https://...
 // TODO: Use a markdown parser instead of rolling our own here.
 export function Linkify(props: { text: string; gray?: boolean }) {
-  let { text, gray } = props
+  const { text, gray } = props
   // Replace "m1234" with "ϻ1234"
   // const mRegex = /(\W|^)m(\d+)/g
   // text = text.replace(mRegex, (_, pre, num) => `${pre}ϻ${num}`)
 
   // Find instances of @username, #hashtag, and https://...
   const regex =
-    /(?:^|\s)(?:[@#][a-z0-9_]+|https?:\/\/[-A-Za-z0-9+&@#\/%?=~_()|!:,.;]*[-A-Za-z0-9+&@#\/%=~_|])/gi
+    /(?:^|\s)(?:[@#][a-z0-9_]+|https?:\/\/[-A-Za-z0-9+&@#/%?=~_()|!:,.;]*[-A-Za-z0-9+&@#/%=~_|])/gi
   const matches = text.match(regex) || []
   const links = matches.map((match) => {
     // Matches are in the form: " @username" or "https://example.com"
diff --git a/web/components/nav/nav-bar.tsx b/web/components/nav/nav-bar.tsx
index 0cb885f5..40a5aacd 100644
--- a/web/components/nav/nav-bar.tsx
+++ b/web/components/nav/nav-bar.tsx
@@ -17,7 +17,7 @@ import { Avatar } from '../avatar'
 import clsx from 'clsx'
 import { useRouter } from 'next/router'
 
-function getNavigation(username: String) {
+function getNavigation(username: string) {
   return [
     { name: 'Home', href: '/home', icon: HomeIcon },
     { name: 'Activity', href: '/activity', icon: ChatAltIcon },
diff --git a/web/components/nav/sidebar.tsx b/web/components/nav/sidebar.tsx
index 1948aae2..962593ed 100644
--- a/web/components/nav/sidebar.tsx
+++ b/web/components/nav/sidebar.tsx
@@ -25,7 +25,7 @@ import {
   useHasCreatedContractToday,
 } from 'web/hooks/use-has-created-contract-today'
 import { Row } from '../layout/row'
-import { useEffect, useState } from 'react'
+import React, { useEffect, useState } from 'react'
 
 // Create an icon from the url of an image
 function IconFromUrl(url: string): React.ComponentType<{ className?: string }> {
@@ -130,7 +130,7 @@ export default function Sidebar(props: { className?: string }) {
     const nextUtcResetTime = getUtcFreeMarketResetTime(false)
     const interval = setInterval(() => {
       const now = new Date().getTime()
-      let timeUntil = nextUtcResetTime - now
+      const timeUntil = nextUtcResetTime - now
       const hoursUntil = timeUntil / 1000 / 60 / 60
       const minutesUntil = Math.floor((hoursUntil * 60) % 60)
       const secondsUntil = Math.floor((hoursUntil * 60 * 60) % 60)
diff --git a/web/components/number-input.tsx b/web/components/number-input.tsx
index a5adb3f8..c40fadeb 100644
--- a/web/components/number-input.tsx
+++ b/web/components/number-input.tsx
@@ -1,5 +1,6 @@
 import clsx from 'clsx'
 
+import React from 'react'
 import { Col } from './layout/col'
 import { Spacer } from './layout/spacer'
 
diff --git a/web/components/outcome-label.tsx b/web/components/outcome-label.tsx
index 394fb6ae..7cbfa144 100644
--- a/web/components/outcome-label.tsx
+++ b/web/components/outcome-label.tsx
@@ -1,4 +1,5 @@
 import clsx from 'clsx'
+import { ReactNode } from 'react'
 import { Answer } from 'common/answer'
 import { getProbability } from 'common/calculate'
 import { getValueFromBucket } from 'common/calculate-dpm'
@@ -156,7 +157,7 @@ export function AnswerLabel(props: {
 
 function FreeResponseAnswerToolTip(props: {
   text: string
-  children?: React.ReactNode
+  children?: ReactNode
 }) {
   const { text } = props
   return (
diff --git a/web/components/page.tsx b/web/components/page.tsx
index faefb718..64830181 100644
--- a/web/components/page.tsx
+++ b/web/components/page.tsx
@@ -1,4 +1,5 @@
 import clsx from 'clsx'
+import { ReactNode } from 'react'
 import { BottomNavBar } from './nav/nav-bar'
 import Sidebar from './nav/sidebar'
 import { Toaster } from 'react-hot-toast'
@@ -6,7 +7,7 @@ import { Toaster } from 'react-hot-toast'
 export function Page(props: {
   margin?: boolean
   assertUser?: 'signed-in' | 'signed-out'
-  rightSidebar?: React.ReactNode
+  rightSidebar?: ReactNode
   suspend?: boolean
   children?: any
 }) {
diff --git a/web/components/site-link.tsx b/web/components/site-link.tsx
index 86fc6c5c..cff47ea5 100644
--- a/web/components/site-link.tsx
+++ b/web/components/site-link.tsx
@@ -1,4 +1,5 @@
 import clsx from 'clsx'
+import { ReactNode } from 'react'
 import Link from 'next/link'
 
 export const SiteLink = (props: {
@@ -30,7 +31,7 @@ export const SiteLink = (props: {
   )
 }
 
-function MaybeLink(props: { href: string; children: React.ReactNode }) {
+function MaybeLink(props: { href: string; children: ReactNode }) {
   const { href, children } = props
   return href.startsWith('http') ? (
     <>{children}</>
diff --git a/web/lib/api/proxy.ts b/web/lib/api/proxy.ts
index 6fa66873..0a386730 100644
--- a/web/lib/api/proxy.ts
+++ b/web/lib/api/proxy.ts
@@ -6,10 +6,10 @@ import fetch, { Headers, Response } from 'node-fetch'
 
 function getProxiedRequestHeaders(req: NextApiRequest, whitelist: string[]) {
   const result = new Headers()
-  for (let name of whitelist) {
+  for (const name of whitelist) {
     const v = req.headers[name.toLowerCase()]
     if (Array.isArray(v)) {
-      for (let vv of v) {
+      for (const vv of v) {
         result.append(name, vv)
       }
     } else if (v != null) {
@@ -23,7 +23,7 @@ function getProxiedRequestHeaders(req: NextApiRequest, whitelist: string[]) {
 
 function getProxiedResponseHeaders(res: Response, whitelist: string[]) {
   const result: { [k: string]: string } = {}
-  for (let name of whitelist) {
+  for (const name of whitelist) {
     const v = res.headers.get(name)
     if (v != null) {
       result[name] = v
diff --git a/web/lib/firebase/init.ts b/web/lib/firebase/init.ts
index 379f7cb6..12f3d832 100644
--- a/web/lib/firebase/init.ts
+++ b/web/lib/firebase/init.ts
@@ -9,13 +9,15 @@ export const app = getApps().length ? getApp() : initializeApp(FIREBASE_CONFIG)
 export const db = getFirestore()
 export const functions = getFunctions()
 
-const EMULATORS_STARTED = 'EMULATORS_STARTED'
+declare global {
+  /* eslint-disable-next-line no-var */
+  var EMULATORS_STARTED: boolean
+}
+
 function startEmulators() {
   // I don't like this but this is the only way to reconnect to the emulators without error, see: https://stackoverflow.com/questions/65066963/firebase-firestore-emulator-error-host-has-been-set-in-both-settings-and-usee
-  // @ts-ignore
-  if (!global[EMULATORS_STARTED]) {
-    // @ts-ignore
-    global[EMULATORS_STARTED] = true
+  if (!global.EMULATORS_STARTED) {
+    global.EMULATORS_STARTED = true
     connectFirestoreEmulator(db, 'localhost', 8080)
     connectFunctionsEmulator(functions, 'localhost', 5001)
   }
diff --git a/web/lib/util/copy.ts b/web/lib/util/copy.ts
index 47dc4dab..66314612 100644
--- a/web/lib/util/copy.ts
+++ b/web/lib/util/copy.ts
@@ -21,7 +21,7 @@ export function copyToClipboard(text: string) {
     document.queryCommandSupported('copy')
   ) {
     console.log('copy 3')
-    var textarea = document.createElement('textarea')
+    const textarea = document.createElement('textarea')
     textarea.textContent = text
     textarea.style.position = 'fixed' // Prevent scrolling to bottom of page in Microsoft Edge.
     document.body.appendChild(textarea)
diff --git a/web/pages/_app.tsx b/web/pages/_app.tsx
index 55618e4c..a833c933 100644
--- a/web/pages/_app.tsx
+++ b/web/pages/_app.tsx
@@ -13,12 +13,12 @@ function firstLine(msg: string) {
 function printBuildInfo() {
   // These are undefined if e.g. dev server
   if (process.env.NEXT_PUBLIC_VERCEL_ENV) {
-    let env = process.env.NEXT_PUBLIC_VERCEL_ENV
-    let msg = process.env.NEXT_PUBLIC_VERCEL_GIT_COMMIT_MESSAGE
-    let owner = process.env.NEXT_PUBLIC_VERCEL_GIT_REPO_OWNER
-    let repo = process.env.NEXT_PUBLIC_VERCEL_GIT_REPO_SLUG
-    let sha = process.env.NEXT_PUBLIC_VERCEL_GIT_COMMIT_SHA
-    let url = `https://github.com/${owner}/${repo}/commit/${sha}`
+    const env = process.env.NEXT_PUBLIC_VERCEL_ENV
+    const msg = process.env.NEXT_PUBLIC_VERCEL_GIT_COMMIT_MESSAGE
+    const owner = process.env.NEXT_PUBLIC_VERCEL_GIT_REPO_OWNER
+    const repo = process.env.NEXT_PUBLIC_VERCEL_GIT_REPO_SLUG
+    const sha = process.env.NEXT_PUBLIC_VERCEL_GIT_COMMIT_SHA
+    const url = `https://github.com/${owner}/${repo}/commit/${sha}`
     console.info(`Build: ${env} / ${firstLine(msg || '???')} / ${url}`)
   }
 }
diff --git a/web/pages/admin.tsx b/web/pages/admin.tsx
index db230e74..e916eb6f 100644
--- a/web/pages/admin.tsx
+++ b/web/pages/admin.tsx
@@ -19,28 +19,22 @@ function avatarHtml(avatarUrl: string) {
 }
 
 function UsersTable() {
-  let users = useUsers()
-  let privateUsers = usePrivateUsers()
+  const users = useUsers()
+  const privateUsers = usePrivateUsers()
 
   // Map private users by user id
   const privateUsersById = mapKeys(privateUsers, 'id')
   console.log('private users by id', privateUsersById)
 
   // For each user, set their email from the PrivateUser
-  users = users.map((user) => {
-    // @ts-ignore
-    user.email = privateUsersById[user.id]?.email
-    return user
-  })
-
-  // Sort users by createdTime descending, by default
-  users = users.sort((a, b) => b.createdTime - a.createdTime)
+  const fullUsers = users
+    .map((user) => {
+      return { email: privateUsersById[user.id]?.email, ...user }
+    })
+    .sort((a, b) => b.createdTime - a.createdTime)
 
   function exportCsv() {
-    const csv = users
-      // @ts-ignore
-      .map((u) => [u.email, u.name].join(', '))
-      .join('\n')
+    const csv = fullUsers.map((u) => [u.email, u.name].join(', ')).join('\n')
     const blob = new Blob([csv], { type: 'text/csv;charset=utf-8' })
     const url = URL.createObjectURL(blob)
     const a = document.createElement('a')
@@ -108,27 +102,29 @@ function UsersTable() {
 }
 
 function ContractsTable() {
-  let contracts = useContracts() ?? []
+  const contracts = useContracts() ?? []
+
   // Sort users by createdTime descending, by default
-  contracts.sort((a, b) => b.createdTime - a.createdTime)
-  // Render a clickable question. See https://gridjs.io/docs/examples/react-cells for docs
-  contracts.map((contract) => {
-    // @ts-ignore
-    contract.questionLink = r(
-      <div className="w-60">
-        <a
-          className="hover:underline hover:decoration-indigo-400 hover:decoration-2"
-          href={contractPath(contract)}
-        >
-          {contract.question}
-        </a>
-      </div>
-    )
-  })
+  const displayContracts = contracts
+    .sort((a, b) => b.createdTime - a.createdTime)
+    .map((contract) => {
+      // Render a clickable question. See https://gridjs.io/docs/examples/react-cells for docs
+      const questionLink = r(
+        <div className="w-60">
+          <a
+            className="hover:underline hover:decoration-indigo-400 hover:decoration-2"
+            href={contractPath(contract)}
+          >
+            {contract.question}
+          </a>
+        </div>
+      )
+      return { questionLink, ...contract }
+    })
 
   return (
     <Grid
-      data={contracts}
+      data={displayContracts}
       columns={[
         {
           id: 'creatorUsername',
diff --git a/web/pages/charity/[charitySlug].tsx b/web/pages/charity/[charitySlug].tsx
index 45933b15..5277f208 100644
--- a/web/pages/charity/[charitySlug].tsx
+++ b/web/pages/charity/[charitySlug].tsx
@@ -1,6 +1,6 @@
 import { sortBy, sumBy, uniqBy } from 'lodash'
 import clsx from 'clsx'
-import { useEffect, useRef, useState } from 'react'
+import React, { useEffect, useRef, useState } from 'react'
 import { Col } from 'web/components/layout/col'
 import { Row } from 'web/components/layout/row'
 import { Page } from 'web/components/page'
diff --git a/web/pages/folds.tsx b/web/pages/folds.tsx
index 749da213..88d6643b 100644
--- a/web/pages/folds.tsx
+++ b/web/pages/folds.tsx
@@ -63,7 +63,7 @@ export default function Folds(props: {
   const [query, setQuery] = useState('')
   // Copied from contracts-list.tsx; extract if we copy this again
   const queryWords = query.toLowerCase().split(' ')
-  function check(corpus: String) {
+  function check(corpus: string) {
     return queryWords.every((word) => corpus.toLowerCase().includes(word))
   }
 
diff --git a/web/pages/profile.tsx b/web/pages/profile.tsx
index ea206f99..ac06eaf2 100644
--- a/web/pages/profile.tsx
+++ b/web/pages/profile.tsx
@@ -1,4 +1,4 @@
-import { useEffect, useState } from 'react'
+import React, { useEffect, useState } from 'react'
 import { RefreshIcon } from '@heroicons/react/outline'
 import Router from 'next/router'
 
@@ -21,7 +21,7 @@ import Textarea from 'react-expanding-textarea'
 
 function EditUserField(props: {
   user: User
-  field: 'bio' | 'bannerUrl' | 'twitterHandle' | 'discordHandle'
+  field: 'bio' | 'website' | 'bannerUrl' | 'twitterHandle' | 'discordHandle'
   label: string
 }) {
   const { user, field, label } = props
@@ -220,18 +220,15 @@ export default function ProfilePage() {
                 }}
               />
 
-              {[
-                ['bio', 'Bio'],
-                ['website', 'Website URL'],
-                ['twitterHandle', 'Twitter'],
-                ['discordHandle', 'Discord'],
-              ].map(([field, label]) => (
-                <EditUserField
-                  user={user}
-                  // @ts-ignore
-                  field={field}
-                  label={label}
-                />
+              {(
+                [
+                  ['bio', 'Bio'],
+                  ['website', 'Website URL'],
+                  ['twitterHandle', 'Twitter'],
+                  ['discordHandle', 'Discord'],
+                ] as const
+              ).map(([field, label]) => (
+                <EditUserField user={user} field={field} label={label} />
               ))}
             </>
           )}