diff --git a/src/function-builder-detectors/README.md b/src/function-builder-detectors/README.md
deleted file mode 100644
index 52af1c62c9e..00000000000
--- a/src/function-builder-detectors/README.md
+++ /dev/null
@@ -1,17 +0,0 @@
-## function builder detectors
-
-similar to project detectors, each file here detects function builders. this is so that netlify dev never manages the
-webpack or other config. the expected output is very simple:
-
-```js
-module.exports = {
-  src: 'functions-source', // source for your functions
-  build: () => {}, // chokidar will call this to build and rebuild your function
-  npmScript: 'build:functions', // optional, the matching package.json script that calls your function builder
-}
-```
-
-example
-
-- [src](https://github.com/netlify/cli/blob/f7b7c6adda3903fa02cf1b3fadcef026a4e56c13/src/function-builder-detectors/netlify-lambda.js#L22)
-- [npmScript](https://github.com/netlify/cli/blob/f7b7c6adda3903fa02cf1b3fadcef026a4e56c13/src/function-builder-detectors/netlify-lambda.js#L23)
diff --git a/src/function-builder-detectors/netlify-lambda.js b/src/lib/functions/runtimes/js/builders/netlify-lambda.js
similarity index 96%
rename from src/function-builder-detectors/netlify-lambda.js
rename to src/lib/functions/runtimes/js/builders/netlify-lambda.js
index ed5d728572b..f4889751846 100644
--- a/src/function-builder-detectors/netlify-lambda.js
+++ b/src/lib/functions/runtimes/js/builders/netlify-lambda.js
@@ -2,7 +2,7 @@ const execa = require('execa')
 const debounce = require('lodash/debounce')
 const minimist = require('minimist')
 
-const { fileExistsAsync, readFileAsync } = require('../lib/fs')
+const { fileExistsAsync, readFileAsync } = require('../../../../fs')
 
 const DEBOUNCE_WAIT = 300
 
diff --git a/src/function-builder-detectors/tests/netlify-lambda.test.js b/src/lib/functions/runtimes/js/builders/tests/netlify-lambda.test.js
similarity index 100%
rename from src/function-builder-detectors/tests/netlify-lambda.test.js
rename to src/lib/functions/runtimes/js/builders/tests/netlify-lambda.test.js
diff --git a/src/function-builder-detectors/zisi.js b/src/lib/functions/runtimes/js/builders/zisi.js
similarity index 95%
rename from src/function-builder-detectors/zisi.js
rename to src/lib/functions/runtimes/js/builders/zisi.js
index 9f16df06a11..7e964c9a215 100644
--- a/src/function-builder-detectors/zisi.js
+++ b/src/lib/functions/runtimes/js/builders/zisi.js
@@ -6,11 +6,11 @@ const makeDir = require('make-dir')
 const pFilter = require('p-filter')
 const sourceMapSupport = require('source-map-support')
 
-const { normalizeFunctionsConfig } = require('../lib/functions/config')
-const { memoizedBuild } = require('../lib/functions/memoized-build')
-const { getPathInProject } = require('../lib/settings')
-const { getFunctions } = require('../utils/get-functions')
-const { NETLIFYDEVERR } = require('../utils/logo')
+const { getFunctions } = require('../../../../../utils/get-functions')
+const { NETLIFYDEVERR } = require('../../../../../utils/logo')
+const { getPathInProject } = require('../../../../settings')
+const { normalizeFunctionsConfig } = require('../../../config')
+const { memoizedBuild } = require('../../../memoized-build')
 
 const ZIP_CONCURRENCY = 5
 
diff --git a/src/utils/detect-functions-builder.js b/src/utils/detect-functions-builder.js
index c3bf5054db3..860f2c29aef 100644
--- a/src/utils/detect-functions-builder.js
+++ b/src/utils/detect-functions-builder.js
@@ -2,14 +2,15 @@ const fs = require('fs')
 const path = require('path')
 
 const detectFunctionsBuilder = async function (parameters) {
+  const buildersPath = path.join(__dirname, '..', 'lib', 'functions', 'runtimes', 'js', 'builders')
   const detectors = fs
-    .readdirSync(path.join(__dirname, '..', 'function-builder-detectors'))
+    .readdirSync(buildersPath)
     // only accept .js detector files
     .filter((filename) => filename.endsWith('.js'))
     // Sorting by filename
     .sort()
     // eslint-disable-next-line node/global-require, import/no-dynamic-require
-    .map((det) => require(path.join(__dirname, '..', `function-builder-detectors/${det}`)))
+    .map((det) => require(path.join(buildersPath, det)))
 
   for (const detector of detectors) {
     // eslint-disable-next-line no-await-in-loop