diff --git a/.github/actions/setup-node-npm-ci/action.yaml b/.github/actions/setup-node-npm-ci/action.yaml
new file mode 100644
index 000000000000..f8e212657351
--- /dev/null
+++ b/.github/actions/setup-node-npm-ci/action.yaml
@@ -0,0 +1,22 @@
+name: Setup Node 20 and run `npm ci`
+description: Uses specified Node version and runs npm commands to set up the environment for REST API CI
+
+inputs:
+  node-version:
+    description: 'Node version to use'
+    default: 20.x
+
+runs:
+  using: "composite"
+
+  steps:
+    - uses: actions/setup-node@v4
+      with:
+        node-version: ${{ inputs.node-version }}
+
+    - run: npm ci
+      shell: bash
+
+    - run: npm ls -a
+      shell: bash
+      continue-on-error: true
diff --git a/.github/workflows/typespec-validation-all.yaml b/.github/workflows/typespec-validation-all.yaml
new file mode 100644
index 000000000000..2ffb641af2e4
--- /dev/null
+++ b/.github/workflows/typespec-validation-all.yaml
@@ -0,0 +1,69 @@
+name: TypeSpec Validation All
+
+on:
+  push:
+    branches:
+      - main
+      - RPSaaSMaster
+      - typespec-next
+
+  pull_request:
+    branches:
+      - main
+      - RPSaaSMaster
+      - typespec-next
+    paths:
+      - .gitattributes
+      - .prettierrc.json
+      - package-lock.json
+      - package.json
+      - tsconfig.json
+      - eng/**
+      - specification/suppressions.yaml
+      - specification/common-types/**
+
+      # Workflow and workflow dependencies
+      - .github/workflows/typespec-validation-all.yaml
+      - .github/actions/setup-node-npm-ci/**
+
+  schedule:
+    # Run 4x/day
+    - cron: '0 0,6,12,18 * * * '
+
+jobs:
+  typespec-validation-all:
+    name: TypeSpec Validation All
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest]
+        # shards must start at 0 and increment by 1
+        shard: [0, 1, 2]
+        # total-shards must be an accurate count of the number of shards
+        total-shards: [3]
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - name: Enable git long paths
+        if: runner.os == 'Windows'
+        run: git config --global core.longpaths true
+
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
+      - name: Setup Node 20 and run `npm ci`
+        uses: ./.github/actions/setup-node-npm-ci
+        
+      - name: Validate All Specs
+        run: |
+          ./eng/scripts/TypeSpec-Validation.ps1 `
+            -Shard ${{ matrix.shard }} `
+            -TotalShards ${{ matrix.total-shards }} `
+            -CheckAll `
+            -GitClean `
+            -Verbose
+          
+          # Effectively the same as ignoreLASTEXITCODE: true in Azure DevOps
+          exit 0
+        shell: pwsh
diff --git a/.github/workflows/typespec-validation.yaml b/.github/workflows/typespec-validation.yaml
new file mode 100644
index 000000000000..0e50527c1761
--- /dev/null
+++ b/.github/workflows/typespec-validation.yaml
@@ -0,0 +1,24 @@
+name: Typespec Validation
+
+on: pull_request
+
+jobs:
+  typespec-validation:
+    name: Typespec Validation
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        fetch-depth: 2
+
+    - name: Setup Node 20 and run `npm ci`
+      uses: ./.github/actions/setup-node-npm-ci
+
+    - name: Validate Impacted Specs
+      run: |
+        ./eng/scripts/TypeSpec-Validation.ps1 -GitClean -Verbose
+        
+        # Effectively the same as ignoreLASTEXITCODE: true in Azure DevOps
+        exit 0
+      shell: pwsh
diff --git a/eng/pipelines/typespec-validation-all.yml b/eng/pipelines/typespec-validation-all.yml
deleted file mode 100644
index e6be95c4bb43..000000000000
--- a/eng/pipelines/typespec-validation-all.yml
+++ /dev/null
@@ -1,47 +0,0 @@
-trigger:
-  branches:
-    include:
-    - main
-    - RPSaaSMaster
-    - typespec-next
-
-resources:
-  pipelines:
-  - pipeline: typespec
-    source: typespec - Publish
-    project: internal
-    trigger:
-      branches:
-        include:
-        - main
-  - pipeline: typespec-azure
-    source: typespec-azure - Publish
-    project: internal
-    trigger:
-      branches:
-        include:
-        - main
-
-jobs:
-- job:
-
-  strategy:
-    matrix:
-      Linux:
-        Pool: azsdk-pool-mms-ubuntu-2204-general
-        OsVmImage: ubuntu-22.04
-      Windows:
-        Pool: azsdk-pool-mms-win-2022-general
-        OsVmImage: windows-2022
-
-  pool:
-    name: $(Pool)
-    vmImage: $(OSVmImage)
-
-  steps:
-  - template: /eng/pipelines/templates/steps/npm-install.yml
-
-  - pwsh: |
-      $(Build.SourcesDirectory)/eng/scripts/TypeSpec-Validation.ps1 -CheckAll -GitClean -Verbose
-    displayName: Validate All Specs
-    ignoreLASTEXITCODE: true
diff --git a/eng/pipelines/typespec-validation.yml b/eng/pipelines/typespec-validation.yml
deleted file mode 100644
index 59729ce5b1f8..000000000000
--- a/eng/pipelines/typespec-validation.yml
+++ /dev/null
@@ -1,16 +0,0 @@
-trigger: none
-
-jobs:
-- job:
-  displayName: Validated Impacted Specs
-  pool:
-    name: azsdk-pool-mms-ubuntu-2204-general
-    vmImage: ubuntu-22.04
-
-  steps:
-  - template: /eng/pipelines/templates/steps/npm-install.yml
-
-  - pwsh: |
-      $(Build.SourcesDirectory)/eng/scripts/TypeSpec-Validation.ps1 -GitClean -Verbose
-    displayName: Validate Impacted Specs
-    ignoreLASTEXITCODE: true
diff --git a/eng/scripts/Array-Functions.ps1 b/eng/scripts/Array-Functions.ps1
new file mode 100644
index 000000000000..d5da35e182b5
--- /dev/null
+++ b/eng/scripts/Array-Functions.ps1
@@ -0,0 +1,18 @@
+function ShardArray($array, $shard, $totalShards) {
+    if ($totalShards -lt 2) { 
+      return $array
+    }
+
+    if ($shard -ge $totalShards) {
+      throw "Shard index ($shard) must be less than total shards ($totalShards)"
+    }
+
+    if ($totalShards -gt $array.Length) {
+      throw "Cannot shard array into more pieces than there are elements"
+    }
+  
+    $shardSize = [math]::Ceiling($array.Length / $totalShards)
+    $start = $shard * $shardSize
+    $end = [math]::Min($start + $shardSize, $array.Length)
+    return $array[$start..($end - 1)]
+  }
diff --git a/eng/scripts/Tests/Array-Functions.Tests.ps1 b/eng/scripts/Tests/Array-Functions.Tests.ps1
new file mode 100644
index 000000000000..923cbe3914f9
--- /dev/null
+++ b/eng/scripts/Tests/Array-Functions.Tests.ps1
@@ -0,0 +1,77 @@
+BeforeAll { 
+    . "$PSScriptRoot\..\Array-Functions.ps1"
+}
+
+# 0..78 makes an array of 79 (prime number) items
+
+Describe "ShardArray" { 
+    Context "Input Validation" { 
+        It "throws when sharding into more pieces than there are elements" { 
+            $array = 0..78
+            $shard = 0
+            $totalShards = 150
+    
+            { ShardArray $array $shard $totalShards } | Should -Throw
+        }
+    
+        It "returns the full array when given <totalShards> shards" -ForEach @( 
+            @{ totalShards = 1 }, 
+            @{ totalShards = 0 }, 
+            @{ totalShards = -1 }, 
+            @{ totalShards = -2 }
+        ) { 
+            $array = 0..78
+            $shard = 0
+    
+            $result = ShardArray $array $shard $totalShards
+    
+            $result | Should -Be $array
+        }
+    
+        It "throws when the shard index is greater than the total shards" { 
+            $array = 0..78
+            $shard = 10
+            $totalShards = 3
+    
+            { ShardArray $array $shard $totalShards } | Should -Throw
+        }
+    
+        It "does not throw when totalShards equals the array length" { 
+            $array = 0..78
+            $shard = 0
+            $totalShards = 79
+    
+            { ShardArray $array $shard $totalShards } | Should -Not -Throw
+        }
+    
+    }
+
+    Context "Shards arrays" -ForEach @(
+        @{ array = 0..78; totalShards = 1 },
+        @{ array = 0..78; totalShards = 2 },
+        @{ array = 0..11; totalShards = 3 }, 
+        @{ array = 0..10; totalShards = 4 }, 
+        @{ array = 0..78; totalShards = 79 }
+    ) {
+        It "returns all of the values in order when sharding (Total Shards: <totalShards>) " { 
+            $shards = New-Object object[] $totalShards
+            for ($i = 0; $i -lt $totalShards; $i++) {
+                # Assigning directly avoids flattening the array.
+                $shards[$i] = ShardArray $array $i $totalShards
+            }
+    
+            # Flatten the array for comparison
+            $actual = $shards | ForEach-Object { $_ }
+    
+            $actual | Should -Be $array
+        }
+
+        It "returns arrays of expected valid size (Total Shards: <totalShards>)" {
+            $maxLength = [math]::Ceiling($array.Length / $totalShards)
+            for ($i = 0; $i -lt $totalShards; $i++) {
+                $shard = ShardArray $array $i $totalShards
+                $shard.Length | Should -BeLessOrEqual $maxLength
+            }
+        }
+    }
+}
diff --git a/eng/scripts/Tests/Copy-ApiVersion/Copy-ApiVersion.Tests.ps1 b/eng/scripts/Tests/Copy-ApiVersion.Tests.ps1
similarity index 75%
rename from eng/scripts/Tests/Copy-ApiVersion/Copy-ApiVersion.Tests.ps1
rename to eng/scripts/Tests/Copy-ApiVersion.Tests.ps1
index 9bbaa3b230b8..a560cafc76f3 100644
--- a/eng/scripts/Tests/Copy-ApiVersion/Copy-ApiVersion.Tests.ps1
+++ b/eng/scripts/Tests/Copy-ApiVersion.Tests.ps1
@@ -1,7 +1,7 @@
 Import-Module Pester
 
 BeforeAll {
-    . "$PSScriptRoot\..\..\Copy-ApiVersion-Functions.ps1"
+    . "$PSScriptRoot\..\Copy-ApiVersion-Functions.ps1"
 }
 
 Describe "Copy-ApiVersion regex tests" {
@@ -11,25 +11,25 @@ Describe "Copy-ApiVersion regex tests" {
                 version       = "2024-01-01-preview"
                 provider      = "Microsoft.AgFoodPlatform"
                 versionStatus = "preview"
-                specsDir      = '..\..\..\..\..\specification\agrifood\resource-manager\Microsoft.AgFoodPlatform\preview\2023-06-01-preview'
+                specsDir      = '..\..\..\..\specification\agrifood\resource-manager\Microsoft.AgFoodPlatform\preview\2023-06-01-preview'
             },
             @{
                 version       = "2024-01-01"
                 provider      = "Microsoft.Compute\ComputeRP"
                 versionStatus = "stable"
-                specsDir      = '..\..\..\..\..\specification\compute\resource-manager\Microsoft.Compute\ComputeRP\stable\2023-09-01'
+                specsDir      = '..\..\..\..\specification\compute\resource-manager\Microsoft.Compute\ComputeRP\stable\2023-09-01'
             },
             @{
                 version       = "7.6-preview.1"
                 provider      = "Microsoft.KeyVault"
                 versionStatus = "preview"
-                specsDir      = '..\..\..\..\..\specification\keyvault\data-plane\Microsoft.KeyVault\preview\7.6-preview.1'
+                specsDir      = '..\..\..\..\specification\keyvault\data-plane\Microsoft.KeyVault\preview\7.6-preview.1'
             },
             @{
                 version       = "7.5"
                 provider      = "Microsoft.Compute\ComputeRP"
                 versionStatus = "stable"
-                specsDir      = '..\..\..\..\..\specification\keyvault\data-plane\Microsoft.KeyVault\stable\7.5'
+                specsDir      = '..\..\..\..\specification\keyvault\data-plane\Microsoft.KeyVault\stable\7.5'
             }
         ) {
             param($version, $provider, $versionStatus, $specsDir)
@@ -48,12 +48,12 @@ Describe "Copy-ApiVersion regex tests" {
         # TODO: This is fragile. The tests stop working when a service team updates their readme.md. We should instead take fixed copies or something.
         It "Default version gets updated" -TestCases @(
             @{
-                inputReadme   = '..\..\..\..\..\specification\compute\resource-manager\readme.md'
+                inputReadme   = '..\..\..\..\specification\compute\resource-manager\readme.md'
                 apiVersion    = "2024-01-01"
                 versionStatus = "stable"
             },
             @{
-                inputReadme   = '..\..\..\..\..\specification\keyvault\data-plane\readme.md'
+                inputReadme   = '..\..\..\..\specification\keyvault\data-plane\readme.md'
                 apiVersion    = "7.6-preview.1"
                 versionStatus = "preview"
             }
diff --git a/eng/scripts/TypeSpec-Validation.ps1 b/eng/scripts/TypeSpec-Validation.ps1
index 031ae7d69000..0b60e6aa0631 100644
--- a/eng/scripts/TypeSpec-Validation.ps1
+++ b/eng/scripts/TypeSpec-Validation.ps1
@@ -1,16 +1,35 @@
 [CmdletBinding()]
 param (
   [switch]$CheckAll = $false,
+  [int]$Shard = 0,
+  [int]$TotalShards = 1,
   [switch]$GitClean = $false,
   [switch]$DryRun = $false,
   [string]$BaseCommitish = "HEAD^",
   [string]$TargetCommitish = "HEAD"
 )
 
+if ($TotalShards -gt 0 -and $Shard -ge $TotalShards) { 
+  throw "Shard ($Shard) must be less than TotalShards ($TotalShards)"
+}
+
 . $PSScriptRoot/Logging-Functions.ps1
 . $PSScriptRoot/Suppressions-Functions.ps1
+. $PSScriptRoot/Array-Functions.ps1
+
+$typespecFolders, $checkedAll = &"$PSScriptRoot/Get-TypeSpec-Folders.ps1" `
+  -BaseCommitish:$BaseCommitish `
+  -TargetCommitish:$TargetCommitish `
+  -CheckAll:$CheckAll
 
-$typespecFolders, $checkedAll = &"$PSScriptRoot/Get-TypeSpec-Folders.ps1" -BaseCommitish:$BaseCommitish -TargetCommitish:$TargetCommitish -CheckAll:$CheckAll
+if ($TotalShards -gt 1 -and $TotalShards -le $typespecFolders.Count) { 
+  $typespecFolders = shardArray $typespecFolders $Shard $TotalShards
+}
+
+Write-Host "Checking $($typespecFolders.Count) TypeSpec folders:"
+foreach ($typespecFolder in $typespecFolders) {
+  Write-Host "  $typespecFolder"
+}
 
 $typespecFoldersWithFailures = @()
 if ($typespecFolders) {