diff --git a/.changeset/dry-days-invite.md b/.changeset/dry-days-invite.md
new file mode 100644
index 0000000000..dcf052acd2
--- /dev/null
+++ b/.changeset/dry-days-invite.md
@@ -0,0 +1,5 @@
+---
+'@backstage/cli': patch
+---
+
+Switch from using deprecated `@esbuild-kit/*` packages to using `tsx`. This also switches to using the new module loader `register` API when available, avoiding the experimental warning when starting backends.
diff --git a/packages/cli/package.json b/packages/cli/package.json
index 419b02d929..9d8b8cfdaa 100644
--- a/packages/cli/package.json
+++ b/packages/cli/package.json
@@ -40,8 +40,6 @@
     "@backstage/integration": "workspace:^",
     "@backstage/release-manifests": "workspace:^",
     "@backstage/types": "workspace:^",
-    "@esbuild-kit/cjs-loader": "^2.4.1",
-    "@esbuild-kit/esm-loader": "^2.5.5",
     "@manypkg/get-packages": "^1.1.3",
     "@octokit/graphql": "^5.0.0",
     "@octokit/graphql-schema": "^13.7.0",
@@ -131,6 +129,7 @@
     "swc-loader": "^0.2.3",
     "tar": "^6.1.12",
     "terser-webpack-plugin": "^5.1.3",
+    "tsx": "^3.14.0",
     "util": "^0.12.3",
     "webpack": "^5.70.0",
     "webpack-dev-server": "^4.7.3",
diff --git a/packages/cli/src/lib/experimental/startBackendExperimental.ts b/packages/cli/src/lib/experimental/startBackendExperimental.ts
index c4271deb3d..cc6d3a940e 100644
--- a/packages/cli/src/lib/experimental/startBackendExperimental.ts
+++ b/packages/cli/src/lib/experimental/startBackendExperimental.ts
@@ -27,11 +27,14 @@ import { isAbsolute as isAbsolutePath } from 'path';
 import { paths } from '../paths';
 import spawn from 'cross-spawn';
 
+const [nodeMajor, nodeMinor] = process.versions.node.split('.').map(Number);
+const supportsModuleLoaderRegister = nodeMajor >= 20 && nodeMinor >= 6;
+
 const loaderArgs = [
   '--require',
-  require.resolve('@esbuild-kit/cjs-loader'),
-  '--loader',
-  pathToFileURL(require.resolve('@esbuild-kit/esm-loader')).toString(), // Windows prefers a URL here
+  require.resolve('tsx/preflight'),
+  supportsModuleLoaderRegister ? '--import' : '--loader',
+  pathToFileURL(require.resolve('tsx')).toString(), // Windows prefers a URL here
 ];
 
 export async function startBackendExperimental(options: BackendServeOptions) {
diff --git a/yarn.lock b/yarn.lock
index 3075745d85..0da2e78684 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3726,8 +3726,6 @@ __metadata:
     "@backstage/test-utils": "workspace:^"
     "@backstage/theme": "workspace:^"
     "@backstage/types": "workspace:^"
-    "@esbuild-kit/cjs-loader": ^2.4.1
-    "@esbuild-kit/esm-loader": ^2.5.5
     "@manypkg/get-packages": ^1.1.3
     "@octokit/graphql": ^5.0.0
     "@octokit/graphql-schema": ^13.7.0
@@ -3837,6 +3835,7 @@ __metadata:
     tar: ^6.1.12
     terser-webpack-plugin: ^5.1.3
     ts-node: ^10.0.0
+    tsx: ^3.14.0
     type-fest: ^2.19.0
     util: ^0.12.3
     webpack: ^5.70.0
@@ -10641,36 +10640,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@esbuild-kit/cjs-loader@npm:^2.4.1":
-  version: 2.4.2
-  resolution: "@esbuild-kit/cjs-loader@npm:2.4.2"
-  dependencies:
-    "@esbuild-kit/core-utils": ^3.0.0
-    get-tsconfig: ^4.4.0
-  checksum: e346e339bfc7eff5c52c270fd0ec06a7f2341b624adfb69f84b7d83f119c35070420906f2761a0b4604e0a0ec90e35eaf12544585476c428ed6d6ee3b250c0fe
-  languageName: node
-  linkType: hard
-
-"@esbuild-kit/core-utils@npm:^3.0.0, @esbuild-kit/core-utils@npm:^3.3.2":
-  version: 3.3.2
-  resolution: "@esbuild-kit/core-utils@npm:3.3.2"
-  dependencies:
-    esbuild: ~0.18.20
-    source-map-support: ^0.5.21
-  checksum: 62f3b97457fa4ef39d752bd2ad1c8adac08929b50c411f5259f105cc74896f1fdb3429a540aa423e8eae37f32ef44656ca21ccb9a723cd9955d65a820960ab1f
-  languageName: node
-  linkType: hard
-
-"@esbuild-kit/esm-loader@npm:^2.5.5":
-  version: 2.6.5
-  resolution: "@esbuild-kit/esm-loader@npm:2.6.5"
-  dependencies:
-    "@esbuild-kit/core-utils": ^3.3.2
-    get-tsconfig: ^4.7.0
-  checksum: 88a27203898f14bd69f03244ae2b3bae727e00243d7801292c4da8caba69813b0978fb8245a55b83bc9b907f475ed634f094a1f44cc590c0754993f4a924cc22
-  languageName: node
-  linkType: hard
-
 "@esbuild/android-arm64@npm:0.16.17":
   version: 0.16.17
   resolution: "@esbuild/android-arm64@npm:0.16.17"
@@ -26652,7 +26621,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"fsevents@npm:2.3.2, fsevents@npm:^2.3.2, fsevents@npm:~2.3.2":
+"fsevents@npm:2.3.2":
   version: 2.3.2
   resolution: "fsevents@npm:2.3.2"
   dependencies:
@@ -26662,7 +26631,17 @@ __metadata:
   languageName: node
   linkType: hard
 
-"fsevents@patch:fsevents@2.3.2#~builtin<compat/fsevents>, fsevents@patch:fsevents@^2.3.2#~builtin<compat/fsevents>, fsevents@patch:fsevents@~2.3.2#~builtin<compat/fsevents>":
+"fsevents@npm:^2.3.2, fsevents@npm:~2.3.2, fsevents@npm:~2.3.3":
+  version: 2.3.3
+  resolution: "fsevents@npm:2.3.3"
+  dependencies:
+    node-gyp: latest
+  checksum: 11e6ea6fea15e42461fc55b4b0e4a0a3c654faa567f1877dbd353f39156f69def97a69936d1746619d656c4b93de2238bf731f6085a03a50cabf287c9d024317
+  conditions: os=darwin
+  languageName: node
+  linkType: hard
+
+"fsevents@patch:fsevents@2.3.2#~builtin<compat/fsevents>":
   version: 2.3.2
   resolution: "fsevents@patch:fsevents@npm%3A2.3.2#~builtin<compat/fsevents>::version=2.3.2&hash=18f3a7"
   dependencies:
@@ -26671,6 +26650,15 @@ __metadata:
   languageName: node
   linkType: hard
 
+"fsevents@patch:fsevents@^2.3.2#~builtin<compat/fsevents>, fsevents@patch:fsevents@~2.3.2#~builtin<compat/fsevents>, fsevents@patch:fsevents@~2.3.3#~builtin<compat/fsevents>":
+  version: 2.3.3
+  resolution: "fsevents@patch:fsevents@npm%3A2.3.3#~builtin<compat/fsevents>::version=2.3.3&hash=18f3a7"
+  dependencies:
+    node-gyp: latest
+  conditions: os=darwin
+  languageName: node
+  linkType: hard
+
 "function-bind@npm:^1.1.1":
   version: 1.1.1
   resolution: "function-bind@npm:1.1.1"
@@ -26861,7 +26849,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"get-tsconfig@npm:^4.4.0, get-tsconfig@npm:^4.7.0":
+"get-tsconfig@npm:^4.7.2":
   version: 4.7.2
   resolution: "get-tsconfig@npm:4.7.2"
   dependencies:
@@ -40881,6 +40869,23 @@ __metadata:
   languageName: node
   linkType: hard
 
+"tsx@npm:^3.14.0":
+  version: 3.14.0
+  resolution: "tsx@npm:3.14.0"
+  dependencies:
+    esbuild: ~0.18.20
+    fsevents: ~2.3.3
+    get-tsconfig: ^4.7.2
+    source-map-support: ^0.5.21
+  dependenciesMeta:
+    fsevents:
+      optional: true
+  bin:
+    tsx: dist/cli.mjs
+  checksum: afcef5d9b90b5800cf1ffb749e943f63042d78a4c0d9eef6e13e43f4ecab465d45e2c9812a2c515cbdc2ee913ff1cd01bf5c606a48013dd3ce2214a631b45557
+  languageName: node
+  linkType: hard
+
 "tty-browserify@npm:0.0.0":
   version: 0.0.0
   resolution: "tty-browserify@npm:0.0.0"