diff --git a/en/blog/blog.11tydata.js b/en/blog/blog.11tydata.js
new file mode 100644
index 0000000..5529a94
--- /dev/null
+++ b/en/blog/blog.11tydata.js
@@ -0,0 +1,30 @@
+module.exports = {
+    eleventyComputed: {
+        // TODO: handle titles as slugs instead of filenames
+        permalink: (data) => {
+            // get the file path stem ie "/en/blog/2025/2025-10-18-my-post"
+            let stem = data.page.filePathStem;
+
+            // strip the leading /en/ prefix
+            if (stem.startsWith("/en/")) {
+                stem = stem.replace(/^\/en/, "");
+            }
+
+            // for blog posts under /blog/[year]/[year-month-day]-blogpost
+            // extract the year and the blog post slug (remove date prefix)
+            const blogPostMatch = stem.match(/^\/blog\/(\d{4})\/\d{4}-\d{2}-\d{2}-(.+)$/);
+            if (blogPostMatch) {
+                const [, year, slug] = blogPostMatch;
+                return `/blog/${year}/${slug}/index.html`; // ie /blog/2025/my-post/index.html
+            }
+
+            // fallback for index or other pages under /blog
+            if (stem.endsWith("/index")) {
+                return `${stem}.html`; // ie /blog/index.html
+            }
+
+            // default for non-index, non-blog-post pages
+            return `${stem}/index.html`;
+        }
+    }
+};
diff --git a/es/blog/blog.11tydata.js b/es/blog/blog.11tydata.js
new file mode 100644
index 0000000..a73f13b
--- /dev/null
+++ b/es/blog/blog.11tydata.js
@@ -0,0 +1,35 @@
+module.exports = {
+    eleventyComputed: {
+        // TODO: handle titles as slugs instead of filenames
+        permalink: (data) => {
+            // get the file path stem, e.g., "/es/blog/2025/2025-10-18-my-post"
+            let stem = data.page.filePathStem;
+
+            // extract the year from the path
+            const yearMatch = stem.match(/^\/es\/blog\/(\d{4})\//);
+            if (yearMatch) {
+                const year = yearMatch[1];
+
+                // check for slug_override first
+                if (data.slug_override) {
+                    return `/es/blog/${year}/${data.slug_override}/index.html`; // ie /es/blog/2025/post-localizado/index.html
+                }
+
+                // handle blog posts with date prefix: /es/blog/[year]/[year-month-day]-slug
+                const blogPostMatch = stem.match(/^\/es\/blog\/(\d{4})\/\d{4}-\d{2}-\d{2}-(.+)$/);
+                if (blogPostMatch) {
+                    const [, , slug] = blogPostMatch;
+                    return `/es/blog/${year}/${this.slugify(slug)}/index.html`; // ie /es/blog/2025/my-post/index.html
+                }
+            }
+
+            // handle index pages or other non-blog-post pages
+            if (stem.endsWith("/index")) {
+                return `${stem}.html`; // ie /es/blog/index.html
+            }
+
+            // default for other pages under /es/blog/
+            return `${stem}/index.html`; // ie /es/other-page/index.html
+        }
+    }
+};
\ No newline at end of file