diff --git a/.env.example b/.env.example
index 136a267..785d327 100644
--- a/.env.example
+++ b/.env.example
@@ -1 +1,15 @@
 PORT="3000"
+# Gitea base url (like https://git.pihkaal.xyz)
+GITEA_URL=""
+# Gitea main username (for me it's pihkaal)
+GITEA_USERNAME=""
+# Create an access token here /user/settings/applications
+# Required permissions:
+#   - read:repository
+#   - read:user
+GITEA_TOKEN=""
+# Create your own in /user/settings/hooks
+GITEA_WEBHOOK_SECRET=""
+# File used by traefik to create the middleware
+TEMPLATE_FILE="gitea-rewrites.yml.in"
+OUTPUT_FILE="gitea-rewrites.yml"
diff --git a/example/gitea-rewrites.yml.in b/example/gitea-rewrites.yml.in
new file mode 100644
index 0000000..771e163
--- /dev/null
+++ b/example/gitea-rewrites.yml.in
@@ -0,0 +1,7 @@
+# example template file
+http:
+  middlewares:
+    gitea-rewrites:
+      replacePathRegex:
+        regex: "^/({{REPOSITORIES}})(.*)$"
+        replacement: "/{{USERNAME}}/$1$2"
diff --git a/src/env.ts b/src/env.ts
index fe6c982..5b4c511 100644
--- a/src/env.ts
+++ b/src/env.ts
@@ -3,7 +3,12 @@ import { z } from "zod";
 
 const schema = z.object({
   PORT: z.coerce.number(),
+  GITEA_URL: z.url(),
+  GITEA_USERNAME: z.string(),
+  GITEA_TOKEN: z.string(),
   GITEA_WEBHOOK_SECRET: z.string(),
+  TEMPLATE_FILE: z.string(),
+  OUTPUT_FILE: z.string(),
 });
 
 const result = schema.safeParse(process.env);
diff --git a/src/sync.ts b/src/sync.ts
new file mode 100644
index 0000000..37f5b62
--- /dev/null
+++ b/src/sync.ts
@@ -0,0 +1,68 @@
+import { readFile, writeFile } from "fs/promises";
+import { z } from "zod";
+import { env } from "./env";
+
+const giteaRepoSchema = z.object({
+  name: z.string(),
+  owner: z.object({
+    login: z.string(),
+  }),
+});
+
+const fetchGiteaRepos = async (): Promise<string[]> => {
+  try {
+    const response = await fetch(
+      `${env.GITEA_URL}/api/v1/users/${env.GITEA_USERNAME}/repos`,
+      {
+        headers: {
+          Authorization: `token ${env.GITEA_TOKEN}`,
+        },
+      },
+    );
+
+    if (!response.ok) {
+      throw new Error(`HTTP ${response.status}: ${response.statusText}`);
+    }
+
+    const json = await response.json();
+    const repos = z.array(giteaRepoSchema).parse(json);
+
+    const userRepos = repos
+      .filter((repo) => repo.owner.login === env.GITEA_USERNAME)
+      .map((repo) => repo.name);
+
+    return userRepos;
+  } catch (error) {
+    console.error(
+      `ERROR: can't fetch repos from Gitea: ${error instanceof Error ? error.message : error}`,
+    );
+    process.exit(1);
+  }
+};
+
+const createOutputFile = async (repos: string[]): Promise<void> => {
+  try {
+    const template = await readFile(env.TEMPLATE_FILE, "utf-8");
+    const reposPattern = repos.join("|");
+
+    let output = template.replace("{{REPOSITORIES}}", reposPattern);
+    output = output.replace("{{USERNAME}}", env.GITEA_USERNAME);
+
+    await writeFile(env.OUTPUT_FILE, output);
+    console.log(`Successfully wrote ${env.OUTPUT_FILE}`);
+  } catch (error) {
+    if (error instanceof Error && "code" in error && error.code === "ENOENT") {
+      console.error(`ERROR: Template file '${env.TEMPLATE_FILE}' not found`);
+    } else {
+      console.error(
+        `ERROR: can't read/write file: ${error instanceof Error ? error.message : error}`,
+      );
+    }
+    process.exit(1);
+  }
+};
+
+export const syncGiteaRewrites = async (): Promise<void> => {
+  const repos = await fetchGiteaRepos();
+  await createOutputFile(repos);
+};