diff --git a/package-lock.json b/package-lock.json
index 9671b4cd7e6..70ddce407ac 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -53,9 +53,7 @@
         "fastest-levenshtein": "1.0.16",
         "fastify": "4.29.0",
         "find-up": "7.0.0",
-        "flush-write-stream": "2.0.0",
         "folder-walker": "3.2.0",
-        "from2-array": "0.0.4",
         "fuzzy": "0.1.3",
         "get-port": "5.1.1",
         "gh-release-fetch": "4.0.3",
@@ -68,7 +66,6 @@
         "inquirer-autocomplete-prompt": "1.4.0",
         "ipx": "2.1.0",
         "is-docker": "3.0.0",
-        "is-stream": "4.0.1",
         "is-wsl": "3.1.0",
         "isexe": "3.1.1",
         "jsonwebtoken": "9.0.2",
@@ -100,8 +97,6 @@
         "strip-ansi-control-characters": "2.0.0",
         "tempy": "3.1.0",
         "terminal-link": "3.0.0",
-        "through2-filter": "4.0.0",
-        "through2-map": "4.0.0",
         "toml": "3.0.0",
         "tomlify-j0.4": "3.0.0",
         "ulid": "2.3.0",
@@ -130,7 +125,6 @@
         "@types/envinfo": "7.8.4",
         "@types/eslint-config-prettier": "^6.11.3",
         "@types/etag": "1.8.3",
-        "@types/flush-write-stream": "1.0.2",
         "@types/folder-walker": "3.2.4",
         "@types/gitconfiglocal": "2.0.3",
         "@types/inquirer": "9.0.7",
@@ -148,7 +142,6 @@
         "@types/semver": "7.5.8",
         "@types/serialize-javascript": "^5.0.4",
         "@types/source-map-support": "0.5.10",
-        "@types/through2-map": "3.0.4",
         "@types/write-file-atomic": "4.0.3",
         "@types/ws": "8.18.0",
         "@vitest/coverage-v8": "1.6.1",
@@ -5026,15 +5019,6 @@
         "@types/range-parser": "*"
       }
     },
-    "node_modules/@types/flush-write-stream": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/@types/flush-write-stream/-/flush-write-stream-1.0.2.tgz",
-      "integrity": "sha512-oCYNbTboisCucq8YBdP97XCmAbI3+Mfpt1XYsedBuZRxWSXsX6LEud8aaACauX3t822XmkdftFCbS+8RvylLWA==",
-      "dev": true,
-      "dependencies": {
-        "@types/node": "*"
-      }
-    },
     "node_modules/@types/folder-walker": {
       "version": "3.2.4",
       "resolved": "https://registry.npmjs.org/@types/folder-walker/-/folder-walker-3.2.4.tgz",
@@ -5272,25 +5256,6 @@
         "@types/node": "*"
       }
     },
-    "node_modules/@types/through2": {
-      "version": "2.0.41",
-      "resolved": "https://registry.npmjs.org/@types/through2/-/through2-2.0.41.tgz",
-      "integrity": "sha512-ryQ0tidWkb1O1JuYvWKyMLYEtOWDqF5mHerJzKz/gQpoAaJq2l/dsMPBF0B5BNVT34rbARYJ5/tsZwLfUi2kwQ==",
-      "dev": true,
-      "dependencies": {
-        "@types/node": "*"
-      }
-    },
-    "node_modules/@types/through2-map": {
-      "version": "3.0.4",
-      "resolved": "https://registry.npmjs.org/@types/through2-map/-/through2-map-3.0.4.tgz",
-      "integrity": "sha512-021N9/i2YhF8oln0JUrYXkfKt9WO6/FqhmsuiolycRGX+u28VUHyFOWh0E5ZuoqS25d99gg71bTmzTA4TbxPiA==",
-      "dev": true,
-      "dependencies": {
-        "@types/node": "*",
-        "@types/through2": "*"
-      }
-    },
     "node_modules/@types/write-file-atomic": {
       "version": "4.0.3",
       "resolved": "https://registry.npmjs.org/@types/write-file-atomic/-/write-file-atomic-4.0.3.tgz",
@@ -11559,15 +11524,6 @@
       "dev": true,
       "license": "ISC"
     },
-    "node_modules/flush-write-stream": {
-      "version": "2.0.0",
-      "resolved": "https://registry.npmjs.org/flush-write-stream/-/flush-write-stream-2.0.0.tgz",
-      "integrity": "sha512-uXClqPxT4xW0lcdSBheb2ObVU+kuqUk3Jk64EwieirEXZx9XUrVwp/JuBfKAWaM4T5Td/VL7QLDWPXp/MvGm/g==",
-      "dependencies": {
-        "inherits": "^2.0.3",
-        "readable-stream": "^3.1.1"
-      }
-    },
     "node_modules/fn.name": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/fn.name/-/fn.name-1.1.0.tgz",
@@ -11694,14 +11650,6 @@
         "readable-stream": "^2.0.0"
       }
     },
-    "node_modules/from2-array": {
-      "version": "0.0.4",
-      "resolved": "https://registry.npmjs.org/from2-array/-/from2-array-0.0.4.tgz",
-      "integrity": "sha512-0G0cAp7sYLobH7ALsr835x98PU/YeVF7wlwxdWbCUaea7wsa7lJfKZUAo6p2YZGZ8F94luCuqHZS3JtFER6uPg==",
-      "dependencies": {
-        "from2": "^2.0.3"
-      }
-    },
     "node_modules/from2/node_modules/readable-stream": {
       "version": "2.3.8",
       "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.8.tgz",
@@ -13171,17 +13119,6 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
-    "node_modules/is-stream": {
-      "version": "4.0.1",
-      "resolved": "https://registry.npmjs.org/is-stream/-/is-stream-4.0.1.tgz",
-      "integrity": "sha512-Dnz92NInDqYckGEUJv689RbRiTSEHCQ7wOVeALbkOz999YpqT46yMRIGtSNl2iCL1waAZSx40+h59NV/EwzV/A==",
-      "engines": {
-        "node": ">=18"
-      },
-      "funding": {
-        "url": "https://github.com/sponsors/sindresorhus"
-      }
-    },
     "node_modules/is-typedarray": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/is-typedarray/-/is-typedarray-1.0.0.tgz",
@@ -17982,36 +17919,6 @@
       "resolved": "https://registry.npmjs.org/through/-/through-2.3.8.tgz",
       "integrity": "sha1-DdTJ/6q8NXlgsbckEV1+Doai4fU="
     },
-    "node_modules/through2": {
-      "version": "4.0.2",
-      "resolved": "https://registry.npmjs.org/through2/-/through2-4.0.2.tgz",
-      "integrity": "sha512-iOqSav00cVxEEICeD7TjLB1sueEL+81Wpzp2bY17uZjZN0pWZPuo4suZ/61VujxmqSGFfgOcNuTZ85QJwNZQpw==",
-      "dependencies": {
-        "readable-stream": "3"
-      }
-    },
-    "node_modules/through2-filter": {
-      "version": "4.0.0",
-      "resolved": "https://registry.npmjs.org/through2-filter/-/through2-filter-4.0.0.tgz",
-      "integrity": "sha512-P8IpQL19bSdXqGLvLdbidYRxERXgHEXGcQofPxbLpPkqS1ieOrUrocdYRTNv8YwSukaDJWr71s6F2kZ3bvgEhA==",
-      "dependencies": {
-        "through2": "^4.0.2"
-      },
-      "engines": {
-        "node": ">= 6"
-      }
-    },
-    "node_modules/through2-map": {
-      "version": "4.0.0",
-      "resolved": "https://registry.npmjs.org/through2-map/-/through2-map-4.0.0.tgz",
-      "integrity": "sha512-+rpmDB5yckiBGEuqJSsWYWMs9e1zdksypDKvByysEyN+knhsPXV9Z6O2mA9meczIa6AON7bi2G3xWk5T8UG4zQ==",
-      "dependencies": {
-        "through2": "^4.0.2"
-      },
-      "engines": {
-        "node": ">= 6"
-      }
-    },
     "node_modules/tinybench": {
       "version": "2.6.0",
       "resolved": "https://registry.npmjs.org/tinybench/-/tinybench-2.6.0.tgz",
@@ -23447,15 +23354,6 @@
         "@types/range-parser": "*"
       }
     },
-    "@types/flush-write-stream": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/@types/flush-write-stream/-/flush-write-stream-1.0.2.tgz",
-      "integrity": "sha512-oCYNbTboisCucq8YBdP97XCmAbI3+Mfpt1XYsedBuZRxWSXsX6LEud8aaACauX3t822XmkdftFCbS+8RvylLWA==",
-      "dev": true,
-      "requires": {
-        "@types/node": "*"
-      }
-    },
     "@types/folder-walker": {
       "version": "3.2.4",
       "resolved": "https://registry.npmjs.org/@types/folder-walker/-/folder-walker-3.2.4.tgz",
@@ -23690,25 +23588,6 @@
         "@types/node": "*"
       }
     },
-    "@types/through2": {
-      "version": "2.0.41",
-      "resolved": "https://registry.npmjs.org/@types/through2/-/through2-2.0.41.tgz",
-      "integrity": "sha512-ryQ0tidWkb1O1JuYvWKyMLYEtOWDqF5mHerJzKz/gQpoAaJq2l/dsMPBF0B5BNVT34rbARYJ5/tsZwLfUi2kwQ==",
-      "dev": true,
-      "requires": {
-        "@types/node": "*"
-      }
-    },
-    "@types/through2-map": {
-      "version": "3.0.4",
-      "resolved": "https://registry.npmjs.org/@types/through2-map/-/through2-map-3.0.4.tgz",
-      "integrity": "sha512-021N9/i2YhF8oln0JUrYXkfKt9WO6/FqhmsuiolycRGX+u28VUHyFOWh0E5ZuoqS25d99gg71bTmzTA4TbxPiA==",
-      "dev": true,
-      "requires": {
-        "@types/node": "*",
-        "@types/through2": "*"
-      }
-    },
     "@types/write-file-atomic": {
       "version": "4.0.3",
       "resolved": "https://registry.npmjs.org/@types/write-file-atomic/-/write-file-atomic-4.0.3.tgz",
@@ -28025,15 +27904,6 @@
       "integrity": "sha512-GX+ysw4PBCz0PzosHDepZGANEuFCMLrnRTiEy9McGjmkCQYwRq4A/X786G/fjM/+OjsWSU1ZrY5qyARZmO/uwg==",
       "dev": true
     },
-    "flush-write-stream": {
-      "version": "2.0.0",
-      "resolved": "https://registry.npmjs.org/flush-write-stream/-/flush-write-stream-2.0.0.tgz",
-      "integrity": "sha512-uXClqPxT4xW0lcdSBheb2ObVU+kuqUk3Jk64EwieirEXZx9XUrVwp/JuBfKAWaM4T5Td/VL7QLDWPXp/MvGm/g==",
-      "requires": {
-        "inherits": "^2.0.3",
-        "readable-stream": "^3.1.1"
-      }
-    },
     "fn.name": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/fn.name/-/fn.name-1.1.0.tgz",
@@ -28134,14 +28004,6 @@
         }
       }
     },
-    "from2-array": {
-      "version": "0.0.4",
-      "resolved": "https://registry.npmjs.org/from2-array/-/from2-array-0.0.4.tgz",
-      "integrity": "sha512-0G0cAp7sYLobH7ALsr835x98PU/YeVF7wlwxdWbCUaea7wsa7lJfKZUAo6p2YZGZ8F94luCuqHZS3JtFER6uPg==",
-      "requires": {
-        "from2": "^2.0.3"
-      }
-    },
     "fs-constants": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/fs-constants/-/fs-constants-1.0.0.tgz",
@@ -29148,11 +29010,6 @@
       "resolved": "https://registry.npmjs.org/is-plain-obj/-/is-plain-obj-4.1.0.tgz",
       "integrity": "sha512-+Pgi+vMuUNkJyExiMBt5IlFoMyKnr5zhJ4Uspz58WOhBF5QoIZkFyNHIbBAtHwzVAgk5RtndVNsDRN61/mmDqg=="
     },
-    "is-stream": {
-      "version": "4.0.1",
-      "resolved": "https://registry.npmjs.org/is-stream/-/is-stream-4.0.1.tgz",
-      "integrity": "sha512-Dnz92NInDqYckGEUJv689RbRiTSEHCQ7wOVeALbkOz999YpqT46yMRIGtSNl2iCL1waAZSx40+h59NV/EwzV/A=="
-    },
     "is-typedarray": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/is-typedarray/-/is-typedarray-1.0.0.tgz",
@@ -32649,30 +32506,6 @@
       "resolved": "https://registry.npmjs.org/through/-/through-2.3.8.tgz",
       "integrity": "sha1-DdTJ/6q8NXlgsbckEV1+Doai4fU="
     },
-    "through2": {
-      "version": "4.0.2",
-      "resolved": "https://registry.npmjs.org/through2/-/through2-4.0.2.tgz",
-      "integrity": "sha512-iOqSav00cVxEEICeD7TjLB1sueEL+81Wpzp2bY17uZjZN0pWZPuo4suZ/61VujxmqSGFfgOcNuTZ85QJwNZQpw==",
-      "requires": {
-        "readable-stream": "3"
-      }
-    },
-    "through2-filter": {
-      "version": "4.0.0",
-      "resolved": "https://registry.npmjs.org/through2-filter/-/through2-filter-4.0.0.tgz",
-      "integrity": "sha512-P8IpQL19bSdXqGLvLdbidYRxERXgHEXGcQofPxbLpPkqS1ieOrUrocdYRTNv8YwSukaDJWr71s6F2kZ3bvgEhA==",
-      "requires": {
-        "through2": "^4.0.2"
-      }
-    },
-    "through2-map": {
-      "version": "4.0.0",
-      "resolved": "https://registry.npmjs.org/through2-map/-/through2-map-4.0.0.tgz",
-      "integrity": "sha512-+rpmDB5yckiBGEuqJSsWYWMs9e1zdksypDKvByysEyN+knhsPXV9Z6O2mA9meczIa6AON7bi2G3xWk5T8UG4zQ==",
-      "requires": {
-        "through2": "^4.0.2"
-      }
-    },
     "tinybench": {
       "version": "2.6.0",
       "resolved": "https://registry.npmjs.org/tinybench/-/tinybench-2.6.0.tgz",
diff --git a/package.json b/package.json
index 25e5766ea07..a9bff45ea33 100644
--- a/package.json
+++ b/package.json
@@ -101,9 +101,7 @@
     "fastest-levenshtein": "1.0.16",
     "fastify": "4.29.0",
     "find-up": "7.0.0",
-    "flush-write-stream": "2.0.0",
     "folder-walker": "3.2.0",
-    "from2-array": "0.0.4",
     "fuzzy": "0.1.3",
     "get-port": "5.1.1",
     "gh-release-fetch": "4.0.3",
@@ -116,7 +114,6 @@
     "inquirer-autocomplete-prompt": "1.4.0",
     "ipx": "2.1.0",
     "is-docker": "3.0.0",
-    "is-stream": "4.0.1",
     "is-wsl": "3.1.0",
     "isexe": "3.1.1",
     "jsonwebtoken": "9.0.2",
@@ -148,8 +145,6 @@
     "strip-ansi-control-characters": "2.0.0",
     "tempy": "3.1.0",
     "terminal-link": "3.0.0",
-    "through2-filter": "4.0.0",
-    "through2-map": "4.0.0",
     "toml": "3.0.0",
     "tomlify-j0.4": "3.0.0",
     "ulid": "2.3.0",
@@ -174,7 +169,6 @@
     "@types/envinfo": "7.8.4",
     "@types/eslint-config-prettier": "^6.11.3",
     "@types/etag": "1.8.3",
-    "@types/flush-write-stream": "1.0.2",
     "@types/folder-walker": "3.2.4",
     "@types/gitconfiglocal": "2.0.3",
     "@types/inquirer": "9.0.7",
@@ -192,7 +186,6 @@
     "@types/semver": "7.5.8",
     "@types/serialize-javascript": "^5.0.4",
     "@types/source-map-support": "0.5.10",
-    "@types/through2-map": "3.0.4",
     "@types/write-file-atomic": "4.0.3",
     "@types/ws": "8.18.0",
     "@vitest/coverage-v8": "1.6.1",
diff --git a/src/lib/functions/runtimes/js/worker.ts b/src/lib/functions/runtimes/js/worker.ts
index 1d0a4989925..c3e271a7516 100644
--- a/src/lib/functions/runtimes/js/worker.ts
+++ b/src/lib/functions/runtimes/js/worker.ts
@@ -2,10 +2,11 @@ import { createServer } from 'net'
 import process from 'process'
 import { isMainThread, workerData, parentPort } from 'worker_threads'
 
-import { isStream } from 'is-stream'
 import lambdaLocal from 'lambda-local'
 import sourceMapSupport from 'source-map-support'
 
+import { isStream } from '../../../../utils/is-stream.js'
+
 if (isMainThread) {
   throw new Error(`Do not import "${import.meta.url}" in the main thread.`)
 }
diff --git a/src/lib/functions/synchronous.ts b/src/lib/functions/synchronous.ts
index a965923999d..107b493f164 100644
--- a/src/lib/functions/synchronous.ts
+++ b/src/lib/functions/synchronous.ts
@@ -1,8 +1,7 @@
 import { Buffer } from 'buffer'
 
-import { isStream } from 'is-stream'
-
 import { chalk, logPadded, NETLIFYDEVERR } from '../../utils/command-helpers.js'
+import { isStream } from '../../utils/is-stream.js'
 import renderErrorTemplate from '../render-error-template.js'
 
 import { detectAwsSdkError } from './utils.js'
diff --git a/src/utils/deploy/hash-fns.ts b/src/utils/deploy/hash-fns.ts
index 2e1ea08ee6c..914608c8ca9 100644
--- a/src/utils/deploy/hash-fns.ts
+++ b/src/utils/deploy/hash-fns.ts
@@ -1,16 +1,15 @@
 import { readFile } from 'fs/promises'
-import path from 'path'
+import * as path from 'path'
 import { pipeline } from 'stream/promises'
 
 import { zipFunctions, type FunctionResult, type TrafficRules } from '@netlify/zip-it-and-ship-it'
-// @ts-expect-error TS(7016) FIXME: Could not find a declaration file for module 'from... Remove this comment to see the full error message
-import fromArray from 'from2-array'
 
 import BaseCommand from '../../commands/base-command.js'
 import { $TSFixMe } from '../../commands/types.js'
 import { INTERNAL_FUNCTIONS_FOLDER } from '../functions/functions.js'
 
 import { hasherCtor, manifestCollectorCtor } from './hasher-segments.js'
+import { Readable } from 'stream'
 
 // Maximum age of functions manifest (2 minutes).
 const MANIFEST_FILE_TTL = 12e4
@@ -211,7 +210,7 @@ const hashFns = async (
     ({ nativeNodeModules }) => nativeNodeModules !== undefined && Object.keys(nativeNodeModules).length !== 0,
   )
 
-  const functionStream = fromArray.obj(fileObjs)
+  const functionStream = Readable.from(fileObjs)
 
   const hasher = hasherCtor({ concurrentHash, hashAlgorithm })
 
diff --git a/src/utils/deploy/hasher-segments.ts b/src/utils/deploy/hasher-segments.ts
index 9a461333db0..1d8db21ddd8 100644
--- a/src/utils/deploy/hasher-segments.ts
+++ b/src/utils/deploy/hasher-segments.ts
@@ -1,12 +1,9 @@
 import { createHash } from 'node:crypto'
 import { createReadStream } from 'node:fs'
+import { Transform, Writable } from 'node:stream'
 import { pipeline } from 'node:stream/promises'
 
-import flushWriteStream from 'flush-write-stream'
 import transform from 'parallel-transform'
-// @ts-expect-error TS(7016) FIXME: Could not find a declaration file for module 'thro... Remove this comment to see the full error message
-import { objCtor as objFilterCtor } from 'through2-filter'
-import { obj as map } from 'through2-map'
 
 import { normalizePath } from './util.js'
 
@@ -36,42 +33,66 @@ export const hasherCtor = ({ concurrentHash, hashAlgorithm }) => {
 }
 
 // Inject normalized file names into normalizedPath and assetType
-// @ts-expect-error TS(7031) FIXME: Binding element 'assetType' implicitly has an 'any... Remove this comment to see the full error message
-export const fileNormalizerCtor = ({ assetType, normalizer: normalizeFunction }) =>
-  map((fileObj) => {
-    const normalizedFile = { ...fileObj, assetType, normalizedPath: normalizePath(fileObj.relname) }
+export const fileNormalizerCtor = ({
+  assetType,
+  normalizer: normalizeFunction,
+}: {
+  assetType: string
+  normalizer?: (file: unknown) => unknown
+}) => {
+  return new Transform({
+    objectMode: true,
+    transform(fileObj, _, callback) {
+      const normalizedFile = { ...fileObj, assetType, normalizedPath: normalizePath(fileObj.relname) }
 
-    if (normalizeFunction !== undefined) {
-      return normalizeFunction(normalizedFile)
-    }
+      const result = normalizeFunction !== undefined ? normalizeFunction(normalizedFile) : normalizedFile
+
+      this.push(result)
 
-    return normalizedFile
+      callback()
+    },
   })
+}
 
 // A writable stream segment ctor that normalizes file paths, and writes shaMap's
-// @ts-expect-error TS(7006) FIXME: Parameter 'filesObj' implicitly has an 'any' type.
-export const manifestCollectorCtor = (filesObj, shaMap, { assetType, statusCb }) => {
+export const manifestCollectorCtor = (
+  filesObj: Record<string, unknown>,
+  shaMap: Record<string, unknown[]>,
+  { assetType, statusCb }: { assetType: string; statusCb: Function },
+) => {
   if (!statusCb || !assetType) throw new Error('Missing required options')
-  return flushWriteStream.obj((fileObj, _, cb) => {
-    filesObj[fileObj.normalizedPath] = fileObj.hash
 
-    // We map a hash to multiple fileObj's because the same file
-    // might live in two different locations
+  return new Writable({
+    objectMode: true,
+    write(fileObj, encoding, callback) {
+      filesObj[fileObj.normalizedPath] = fileObj.hash
 
-    if (Array.isArray(shaMap[fileObj.hash])) {
-      shaMap[fileObj.hash].push(fileObj)
-    } else {
-      shaMap[fileObj.hash] = [fileObj]
-    }
-    statusCb({
-      type: 'hashing',
-      msg: `Hashing ${fileObj.relname}`,
-      phase: 'progress',
-    })
-    cb()
+      // Maintain hash to fileObj mapping
+      if (Array.isArray(shaMap[fileObj.hash])) {
+        shaMap[fileObj.hash].push(fileObj)
+      } else {
+        shaMap[fileObj.hash] = [fileObj]
+      }
+
+      statusCb({
+        type: 'hashing',
+        msg: `Hashing ${fileObj.relname}`,
+        phase: 'progress',
+      })
+
+      callback()
+    },
   })
 }
 
-// transform stream ctor that filters folder-walker results for only files
-// @ts-expect-error TS(7006) FIXME: Parameter 'fileObj' implicitly has an 'any' type.
-export const fileFilterCtor = objFilterCtor((fileObj) => fileObj.type === 'file')
+export const fileFilterCtor = () =>
+  new Transform({
+    objectMode: true,
+    transform(fileObj, _, callback) {
+      if (fileObj.type === 'file') {
+        this.push(fileObj)
+      }
+      // eslint-disable-next-line promise/prefer-await-to-callbacks
+      callback()
+    },
+  })
diff --git a/src/utils/is-stream.ts b/src/utils/is-stream.ts
new file mode 100644
index 00000000000..e147f5b5bbc
--- /dev/null
+++ b/src/utils/is-stream.ts
@@ -0,0 +1,4 @@
+import type { Stream } from 'node:stream'
+
+export const isStream = (stream: unknown): stream is Stream =>
+  stream !== null && typeof stream === 'object' && typeof (stream as Stream).pipe === 'function'