diff --git a/.changeset/sour-buttons-collect.md b/.changeset/sour-buttons-collect.md
new file mode 100644
index 0000000000..09c7cfd167
--- /dev/null
+++ b/.changeset/sour-buttons-collect.md
@@ -0,0 +1,5 @@
+---
+'@backstage/cli': patch
+---
+
+ensure that `productionPack` uses posix paths in `package.json` on all OSes
diff --git a/.github/vale/Vocab/Backstage/accept.txt b/.github/vale/Vocab/Backstage/accept.txt
index f058475367..83fba8aa56 100644
--- a/.github/vale/Vocab/Backstage/accept.txt
+++ b/.github/vale/Vocab/Backstage/accept.txt
@@ -267,6 +267,7 @@ permissioning
 plantuml
 Platformize
 Podman
+posix
 postgres
 postpack
 pre
diff --git a/package.json b/package.json
index 8550a72a97..3825b2e64c 100644
--- a/package.json
+++ b/package.json
@@ -8,7 +8,7 @@
     "dev": "concurrently \"yarn start\" \"yarn start-backend\"",
     "start": "yarn workspace example-app start",
     "start-backend": "yarn workspace example-backend start",
-    "build:backend": "yarn workspace backend build",
+    "build:backend": "yarn workspace example-backend build",
     "build:all": "backstage-cli repo build --all",
     "build:api-reports": "yarn build:api-reports:only --tsc",
     "build:api-reports:only": "backstage-repo-tools api-reports --allow-warnings 'packages/core-components,plugins/+(catalog|catalog-import|git-release-manager|jenkins|kubernetes)' -o ae-wrong-input-file-type --validate-release-tags",
diff --git a/packages/cli/src/lib/packager/productionPack.ts b/packages/cli/src/lib/packager/productionPack.ts
index a26f4893d0..30f4545b24 100644
--- a/packages/cli/src/lib/packager/productionPack.ts
+++ b/packages/cli/src/lib/packager/productionPack.ts
@@ -16,7 +16,7 @@
 
 import fs from 'fs-extra';
 import npmPackList from 'npm-packlist';
-import { join as joinPath, resolve as resolvePath } from 'path';
+import { resolve as resolvePath, posix as posixPath } from 'path';
 import { ExtendedPackageJSON } from '../monorepo';
 import { readEntryPoints } from '../monorepo/entryPoints';
 
@@ -142,7 +142,7 @@ export async function revertProductionPack(packageDir: string) {
 
 function resolveEntrypoint(pkg: any, name: string) {
   const targetEntry = pkg.publishConfig[name] || pkg[name];
-  return targetEntry && joinPath('..', targetEntry);
+  return targetEntry && posixPath.join('..', targetEntry);
 }
 
 // Writes e.g. alpha/package.json
@@ -160,7 +160,7 @@ async function writeReleaseStageEntrypoint(
       main: resolveEntrypoint(pkg, 'main'),
       module: resolveEntrypoint(pkg, 'module'),
       browser: resolveEntrypoint(pkg, 'browser'),
-      types: joinPath('..', pkg.publishConfig![`${stage}Types`]!),
+      types: posixPath.join('..', pkg.publishConfig![`${stage}Types`]!),
     },
     { encoding: 'utf8', spaces: 2 },
   );
@@ -202,7 +202,7 @@ async function prepareExportsEntryPoints(
     for (const [key, ext] of Object.entries(EXPORT_MAP)) {
       const name = `${entryPoint.name}${ext}`;
       if (distFiles.includes(name)) {
-        exp[key] = `./${joinPath(`dist`, name)}`;
+        exp[key] = `./${posixPath.join(`dist`, name)}`;
       }
     }
     exp.default = exp.require ?? exp.import;
@@ -228,9 +228,9 @@ async function prepareExportsEntryPoints(
           {
             name: pkg.name,
             version: pkg.version,
-            ...(exp.default ? { main: joinPath('..', exp.default) } : {}),
-            ...(exp.import ? { module: joinPath('..', exp.import) } : {}),
-            ...(exp.types ? { types: joinPath('..', exp.types) } : {}),
+            ...(exp.default ? { main: posixPath.join('..', exp.default) } : {}),
+            ...(exp.import ? { module: posixPath.join('..', exp.import) } : {}),
+            ...(exp.types ? { types: posixPath.join('..', exp.types) } : {}),
           },
           { encoding: 'utf8', spaces: 2 },
         );