diff --git a/.circleci/config.yml b/.circleci/config.yml
index e8d0f9519ce9a..5ecefdfba2294 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -63,6 +63,7 @@ aliases:
           - /blog.+/
 
   test_template: &test_template
+    parallelism: 4
     parameters:
       npm_rebuild:
         type: boolean
@@ -75,11 +76,16 @@ aliases:
           condition: << parameters.npm_rebuild >>
           steps:
             - run: npm rebuild
-      - run: yarn list react
-      - run: yarn why lmdb-store
       - run:
-          command: node --max-old-space-size=2048 ./node_modules/.bin/jest -w 1 --ci
+          name: Step debug info
+          command: |
+            yarn list react
+            yarn why lmdb-store
+      - run:
+          name: Run tests
+          command: yarn jest --ci --runInBand $(yarn jest --listTests | sed 's/\/root\/project//g' | circleci tests split --split-by=timings)
           environment:
+            NODE_OPTIONS: --max-old-space-size=2048
             GENERATE_JEST_REPORT: true
             JEST_JUNIT_OUTPUT_DIR: ./test-results/jest-node/
             JEST_JUNIT_OUTPUT_NAME: results.xml
@@ -193,7 +199,8 @@ jobs:
       - persist_to_workspace:
           root: ./
           paths:
-            - "*"
+            - "packages/"
+            - "node_modules/"
 
   lint:
     executor: node
@@ -506,6 +513,7 @@ jobs:
           working_directory: ~/project/scripts/i18n
 
   windows_unit_tests:
+    parallelism: 4
     executor:
       name: win/default
       shell: powershell.exe
@@ -519,28 +527,30 @@ jobs:
       #     keys:
       #       - yarn-packages-v2-{{ checksum "yarn.lock" }}
       #       - yarn-packages-v2-
+
+      - <<: *attach_to_bootstrap
       - run:
-          name: Install node 12.13
+          name: Install node 12.13 and yarn
           command: |
             nvm install 12.13.0
             nvm alias default 12.13.0
             nvm use 12.13.0
             choco install yarn
       - run:
-          name: Set yarn timeout
-          command: yarn config set network-timeout 300000
-      - run:
-          name: Install node modules
-          command: yarn --frozen-lockfile
-      # Caching is slow, so disabling
-      # - save_cache:
-      #     paths:
-      #       - C:\Users\circleci\AppData\Local\Yarn\Cache
-      #     key: yarn-packages-v2-{{ checksum "yarn.lock" }}
-      - run: yarn npm-run-all -s check-versions "lerna-prepare --concurrency=4 --stream"
+          name: Rebuild packages for windows
+          command: |
+            Remove-Item -Recurse -Force -Path "node_modules/sharp/"
+            yarn
       - run:
-          name: "Run Tests"
-          command: yarn jest -w 1 --ci
+          name: Run tests
+          command: yarn jest --ci --runInBand ((yarn jest --listTests) | Foreach-Object {$_ -replace '.*\\packages', 'packages'} | Foreach-Object {$_ -replace '\\', '/'} | circleci tests split --split-by=timings)
+          environment:
+            NODE_OPTIONS: --max-old-space-size=2048
+            GENERATE_JEST_REPORT: true
+            JEST_JUNIT_OUTPUT_DIR: ./test-results/jest-node/
+            JEST_JUNIT_OUTPUT_NAME: results.xml
+      - store_test_results:
+          path: ./test-results/jest-node/
 
   bootstrap-with-experimental-react:
     executor: node
@@ -627,6 +637,7 @@ workflows:
           <<: *ignore_docs
           requires:
             - lint
+            - bootstrap
       - unit_tests_node12:
           <<: *ignore_docs
           requires:
diff --git a/e2e-tests/production-runtime/cypress/integration/resource-loading-resilience.js b/e2e-tests/production-runtime/cypress/integration/resource-loading-resilience.js
index 1e0fc62f9750f..fb563316b4847 100644
--- a/e2e-tests/production-runtime/cypress/integration/resource-loading-resilience.js
+++ b/e2e-tests/production-runtime/cypress/integration/resource-loading-resilience.js
@@ -1,5 +1,5 @@
 const waitForAPIOptions = {
-  timeout: 10000,
+  timeout: 5000,
 }
 
 function runTests(testNameSuffix) {
diff --git a/packages/gatsby/src/utils/worker/__tests__/config.ts b/packages/gatsby/src/utils/worker/__tests__/config.ts
index e2b601481f7cc..239979f1ae025 100644
--- a/packages/gatsby/src/utils/worker/__tests__/config.ts
+++ b/packages/gatsby/src/utils/worker/__tests__/config.ts
@@ -4,6 +4,13 @@ import * as path from "path"
 
 let worker: GatsbyTestWorkerPool | undefined
 
+jest.mock(`gatsby-telemetry`, () => {
+  return {
+    decorateEvent: jest.fn(),
+    trackCli: jest.fn(),
+  }
+})
+
 beforeEach(() => {
   store.dispatch({ type: `DELETE_CACHE` })
 })
diff --git a/packages/gatsby/src/utils/worker/__tests__/datastore.ts b/packages/gatsby/src/utils/worker/__tests__/datastore.ts
index 246733e376a89..b215d0ae53b29 100644
--- a/packages/gatsby/src/utils/worker/__tests__/datastore.ts
+++ b/packages/gatsby/src/utils/worker/__tests__/datastore.ts
@@ -7,6 +7,18 @@ import { store } from "../../../redux"
 import { actions } from "../../../redux/actions"
 import { getDataStore } from "../../../datastore"
 
+jest.mock(`gatsby-telemetry`, () => {
+  return {
+    decorateEvent: jest.fn(),
+    trackError: jest.fn(),
+    trackCli: jest.fn(),
+  }
+})
+
+jest.mock(`gatsby-cli/lib/reporter`, () => {
+  return {}
+})
+
 let worker: GatsbyTestWorkerPool | undefined
 
 beforeEach(() => {
diff --git a/packages/gatsby/src/utils/worker/__tests__/jobs.ts b/packages/gatsby/src/utils/worker/__tests__/jobs.ts
index e42a9affd9ca5..28f3bd9c079a8 100644
--- a/packages/gatsby/src/utils/worker/__tests__/jobs.ts
+++ b/packages/gatsby/src/utils/worker/__tests__/jobs.ts
@@ -6,6 +6,15 @@ import { waitUntilAllJobsComplete } from "../../jobs/manager"
 import type { MessagesFromChild, MessagesFromParent } from "../messaging"
 import { getReduxJobs, getJobsMeta } from "./test-helpers/child-for-tests"
 
+jest.mock(`gatsby-telemetry`, () => {
+  return {
+    decorateEvent: jest.fn(),
+    trackCli: jest.fn(),
+  }
+})
+
+// jest.mock(`gatsby-cli/lib/reporter`, () => jest.fn())
+
 let worker: GatsbyTestWorkerPool | undefined
 
 describe(`worker (jobs)`, () => {
diff --git a/packages/gatsby/src/utils/worker/__tests__/queries.ts b/packages/gatsby/src/utils/worker/__tests__/queries.ts
index fdcceadc467c1..6d33c2eb4541c 100644
--- a/packages/gatsby/src/utils/worker/__tests__/queries.ts
+++ b/packages/gatsby/src/utils/worker/__tests__/queries.ts
@@ -44,6 +44,14 @@ jest.mock(`chokidar`, () => {
   return chokidar
 })
 
+jest.mock(`gatsby-telemetry`, () => {
+  return {
+    decorateEvent: jest.fn(),
+    trackError: jest.fn(),
+    trackCli: jest.fn(),
+  }
+})
+
 const dummyKeys = `a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z`.split(
   `,`
 )
diff --git a/packages/gatsby/src/utils/worker/__tests__/schema.ts b/packages/gatsby/src/utils/worker/__tests__/schema.ts
index 6eb132a58d020..33e42dc742ae5 100644
--- a/packages/gatsby/src/utils/worker/__tests__/schema.ts
+++ b/packages/gatsby/src/utils/worker/__tests__/schema.ts
@@ -37,6 +37,14 @@ jest.mock(`chokidar`, () => {
   return chokidar
 })
 
+jest.mock(`gatsby-telemetry`, () => {
+  return {
+    decorateEvent: jest.fn(),
+    trackError: jest.fn(),
+    trackCli: jest.fn(),
+  }
+})
+
 describeWhenLMDB(`worker (schema)`, () => {
   let stateFromWorker: CombinedState<IGatsbyState>
 
diff --git a/packages/gatsby/src/utils/worker/__tests__/share-state.ts b/packages/gatsby/src/utils/worker/__tests__/share-state.ts
index c4e793afa34f2..2be3661ce3a68 100644
--- a/packages/gatsby/src/utils/worker/__tests__/share-state.ts
+++ b/packages/gatsby/src/utils/worker/__tests__/share-state.ts
@@ -7,6 +7,14 @@ import {
 } from "../../../redux"
 import { GatsbyStateKeys } from "../../../redux/types"
 
+jest.mock(`gatsby-telemetry`, () => {
+  return {
+    decorateEvent: jest.fn(),
+    trackError: jest.fn(),
+    trackCli: jest.fn(),
+  }
+})
+
 let worker: GatsbyTestWorkerPool | undefined
 
 const dummyPagePayload = {