diff --git a/legacy/package.json b/legacy/package.json
index a25ace0f..423b15f3 100644
--- a/legacy/package.json
+++ b/legacy/package.json
@@ -37,11 +37,12 @@
   "dependencies": {
     "@dqbd/tiktoken": "^1.0.7",
     "dotenv-safe": "^8.2.0",
+    "handlebars": "^4.7.7",
     "jsonrepair": "^3.1.0",
     "ky": "^0.33.3",
-    "mustache": "^4.2.0",
     "openai-fetch": "^1.3.0",
     "p-map": "^6.0.0",
+    "quick-lru": "^6.1.1",
     "ts-dedent": "^2.2.0",
     "type-fest": "^3.11.0",
     "zod": "^3.21.4",
@@ -50,7 +51,6 @@
   },
   "devDependencies": {
     "@trivago/prettier-plugin-sort-imports": "^4.1.1",
-    "@types/mustache": "^4.2.2",
     "@types/node": "^20.2.5",
     "ava": "^5.3.0",
     "del-cli": "^5.0.0",
diff --git a/legacy/pnpm-lock.yaml b/legacy/pnpm-lock.yaml
index b737b9f5..8b172185 100644
--- a/legacy/pnpm-lock.yaml
+++ b/legacy/pnpm-lock.yaml
@@ -7,21 +7,24 @@ dependencies:
   dotenv-safe:
     specifier: ^8.2.0
     version: 8.2.0
+  handlebars:
+    specifier: ^4.7.7
+    version: 4.7.7
   jsonrepair:
     specifier: ^3.1.0
     version: 3.1.0
   ky:
     specifier: ^0.33.3
     version: 0.33.3
-  mustache:
-    specifier: ^4.2.0
-    version: 4.2.0
   openai-fetch:
     specifier: ^1.3.0
     version: 1.3.0
   p-map:
     specifier: ^6.0.0
     version: 6.0.0
+  quick-lru:
+    specifier: ^6.1.1
+    version: 6.1.1
   ts-dedent:
     specifier: ^2.2.0
     version: 2.2.0
@@ -42,9 +45,6 @@ devDependencies:
   '@trivago/prettier-plugin-sort-imports':
     specifier: ^4.1.1
     version: 4.1.1(prettier@2.8.8)
-  '@types/mustache':
-    specifier: ^4.2.2
-    version: 4.2.2
   '@types/node':
     specifier: ^20.2.5
     version: 20.2.5
@@ -494,10 +494,6 @@ packages:
     resolution: {integrity: sha512-jhuKLIRrhvCPLqwPcx6INqmKeiA5EWrsCOPhrlFSrbrmU4ZMPjj5Ul/oLCMDO98XRUIwVm78xICz4EPCektzeQ==}
     dev: true
 
-  /@types/mustache@4.2.2:
-    resolution: {integrity: sha512-MUSpfpW0yZbTgjekDbH0shMYBUD+X/uJJJMm9LXN1d5yjl5lCY1vN/eWKD6D1tOtjA6206K0zcIPnUaFMurdNA==}
-    dev: true
-
   /@types/node@20.2.5:
     resolution: {integrity: sha512-JJulVEQXmiY9Px5axXHeYGLSjhkZEnD+MDPDGbCbIAbMslkKwmygtZFy1X6s/075Yo94sf8GuSlFfPzysQrWZQ==}
     dev: true
@@ -1404,6 +1400,19 @@ packages:
     resolution: {integrity: sha512-RbJ5/jmFcNNCcDV5o9eTnBLJ/HszWV0P73bc+Ff4nS/rJj+YaS6IGyiOL0VoBYX+l1Wrl3k63h/KrH+nhJ0XvQ==}
     dev: true
 
+  /handlebars@4.7.7:
+    resolution: {integrity: sha512-aAcXm5OAfE/8IXkcZvCepKU3VzW1/39Fb5ZuqMtgI/hT8X2YgoMvBY5dLhq/cpOvw7Lk1nK/UF71aLG/ZnVYRA==}
+    engines: {node: '>=0.4.7'}
+    hasBin: true
+    dependencies:
+      minimist: 1.2.8
+      neo-async: 2.6.2
+      source-map: 0.6.1
+      wordwrap: 1.0.0
+    optionalDependencies:
+      uglify-js: 3.17.4
+    dev: false
+
   /hard-rejection@2.1.0:
     resolution: {integrity: sha512-VIZB+ibDhx7ObhAe7OVtoEbuP4h/MuOTHJ+J8h/eBXotJYl0fBgR72xDFCKgIh22OJZIOVNxBMWuhAr10r8HdA==}
     engines: {node: '>=6'}
@@ -1981,6 +1990,10 @@ packages:
       kind-of: 6.0.3
     dev: true
 
+  /minimist@1.2.8:
+    resolution: {integrity: sha512-2yyAR8qBkN3YuheJanUpWC5U3bb5osDywNB8RzDVlDwDHbocAJveqqj1u8+SVD7jkWT4yvsHCpWqqWqAxb0zCA==}
+    dev: false
+
   /ms@2.1.2:
     resolution: {integrity: sha512-sGkPx+VjMtmA6MX27oA4FBFELFCZZ4S4XqeGOXCv68tT+jb3vk/RyaKWP0PTKyWtmLSM0b+adUTEvbs1PEaH2w==}
     dev: true
@@ -1989,11 +2002,6 @@ packages:
     resolution: {integrity: sha512-6FlzubTLZG3J2a/NVCAleEhjzq5oxgHyaCU9yYXvcLsvoVaHJq/s5xXI6/XXP6tz7R9xAOtHnSO/tXtF3WRTlA==}
     dev: true
 
-  /mustache@4.2.0:
-    resolution: {integrity: sha512-71ippSywq5Yb7/tVYyGbkBggbU8H3u5Rz56fH60jGFgr8uHwxs+aSKeqmluIVzM0m0kB7xQjKS6qPfd0b2ZoqQ==}
-    hasBin: true
-    dev: false
-
   /mz@2.7.0:
     resolution: {integrity: sha512-z81GNO7nnYMEhrGh9LeymoE4+Yr0Wn5McHIZMK5cfQCl+NDX08sCZgUc9/6MHni9IWuFLm1Z3HTCXu2z9fN62Q==}
     dependencies:
@@ -2002,6 +2010,10 @@ packages:
       thenify-all: 1.6.0
     dev: true
 
+  /neo-async@2.6.2:
+    resolution: {integrity: sha512-Yd3UES5mWCSqR+qNT93S3UoYUkqAZ9lLg8a7g9rimsWmYGK8cVToA4/sF3RrshdyV3sAGMXVUmpMYOw+dLpOuw==}
+    dev: false
+
   /nice-try@1.0.5:
     resolution: {integrity: sha512-1nh45deeb5olNY7eX82BkPO7SSxR5SSYJiPTrTdFUVYwAl8CKMA5N9PjTYkHiRjisVcxcQ1HXdLhx2qxxJzLNQ==}
     dev: true
@@ -2334,6 +2346,11 @@ packages:
     engines: {node: '>=10'}
     dev: true
 
+  /quick-lru@6.1.1:
+    resolution: {integrity: sha512-S27GBT+F0NTRiehtbrgaSE1idUAJ5bX8dPAQTdylEyNlrdcH5X4Lz7Edz3DYzecbsCluD5zO8ZNEe04z3D3u6Q==}
+    engines: {node: '>=12'}
+    dev: false
+
   /read-pkg-up@8.0.0:
     resolution: {integrity: sha512-snVCqPczksT0HS2EC+SxUndvSzn6LRCwpfSvLrIfR5BKDQQZMaI6jPRC9dYvYFDRAuFEAnkwww8kBBNE/3VvzQ==}
     engines: {node: '>=12'}
@@ -2580,7 +2597,6 @@ packages:
   /source-map@0.6.1:
     resolution: {integrity: sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g==}
     engines: {node: '>=0.10.0'}
-    dev: true
 
   /source-map@0.8.0-beta.0:
     resolution: {integrity: sha512-2ymg6oRBpebeZi9UUNsgQ89bhx01TcTkmNTGnNO88imTmbSgy4nfujrgVEFKWpMTEGA11EDkTt7mqObTPdigIA==}
@@ -2899,6 +2915,14 @@ packages:
     engines: {node: '>=12.20'}
     hasBin: true
 
+  /uglify-js@3.17.4:
+    resolution: {integrity: sha512-T9q82TJI9e/C1TAxYvfb16xO120tMVFZrGA3f9/P4424DNu6ypK103y0GPFVa17yotwSyZW5iYXgjYHkGrJW/g==}
+    engines: {node: '>=0.8.0'}
+    hasBin: true
+    requiresBuild: true
+    dev: false
+    optional: true
+
   /unbox-primitive@1.0.2:
     resolution: {integrity: sha512-61pPlCD9h51VoreyJ0BReideM3MDKMKnh6+V9L08331ipq6Q8OFXZYiqP6n/tbHx4s5I9uRhcye6BrbkizkBDw==}
     dependencies:
@@ -2969,6 +2993,10 @@ packages:
       isexe: 2.0.0
     dev: true
 
+  /wordwrap@1.0.0:
+    resolution: {integrity: sha512-gvVzJFlPycKc5dZN4yPkP8w7Dc37BtP1yczEneOb4uq34pXZcvrtRTmWV8W+Ume+XCxKgbjM+nevkyFPMybd4Q==}
+    dev: false
+
   /wrap-ansi@6.2.0:
     resolution: {integrity: sha512-r6lPcBGxZXlIcymEu7InxDMhdW0KDxpLgoFLcguasxCaJ/SOIZwINatK9KY/tf+ZrlywOKU0UDj3ATXUBfxJXA==}
     engines: {node: '>=8'}
diff --git a/legacy/src/llm.ts b/legacy/src/llm.ts
index 25837b68..bc07719a 100644
--- a/legacy/src/llm.ts
+++ b/legacy/src/llm.ts
@@ -1,11 +1,11 @@
 import { jsonrepair } from 'jsonrepair'
-import Mustache from 'mustache'
 import { dedent } from 'ts-dedent'
 import { ZodRawShape, ZodTypeAny, z } from 'zod'
 import { printNode, zodToTs } from 'zod-to-ts'
 
 import * as types from './types'
 import { BaseTaskCallBuilder } from './task'
+import { getCompiledTemplate } from './template'
 import {
   extractJSONArrayFromString,
   extractJSONObjectFromString
@@ -105,7 +105,7 @@ export abstract class BaseChatModelBuilder<
         return {
           ...message,
           content: message.content
-            ? Mustache.render(dedent(message.content), input).trim()
+            ? getCompiledTemplate(dedent(message.content))(input).trim()
             : ''
         }
       })
diff --git a/legacy/src/template.ts b/legacy/src/template.ts
new file mode 100644
index 00000000..d12a6b31
--- /dev/null
+++ b/legacy/src/template.ts
@@ -0,0 +1,19 @@
+import Handlebars from 'handlebars'
+import QuickLRU from 'quick-lru'
+
+const lru = new QuickLRU({ maxSize: 1000 })
+
+export function getCompiledTemplate(template: string) {
+  let compiledTemplate = lru.get(template) as HandlebarsTemplateDelegate
+
+  if (compiledTemplate) {
+    return compiledTemplate
+  }
+
+  compiledTemplate = Handlebars.compile(template, {
+    noEscape: true
+  })
+
+  lru.set(template, compiledTemplate)
+  return compiledTemplate
+}