diff --git a/.github/workflows/update-monitor.yml b/.github/workflows/update-monitor.yml
index 57940d4..d0c29e0 100644
--- a/.github/workflows/update-monitor.yml
+++ b/.github/workflows/update-monitor.yml
@@ -9,7 +9,7 @@ jobs:
   UpdateMonitor:
     runs-on: ubuntu-latest
     steps:
-      - uses: floric/repo-monitor-action@v0.0.10
+      - uses: floric/repo-monitor-action@v0.0.11
         with:
           key: bundle-size
           value: 1
diff --git a/action.yml b/action.yml
index 51de9d4..5479d70 100644
--- a/action.yml
+++ b/action.yml
@@ -10,4 +10,4 @@ inputs:
     required: true
 runs:
   using: "node12"
-  main: "index.js"
+  main: "dist/index.js"
diff --git a/dist/index.js b/dist/index.js
new file mode 100644
index 0000000..fbecd22
--- /dev/null
+++ b/dist/index.js
@@ -0,0 +1,56 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+const core = require("@actions/core");
+const github = require("@actions/github");
+async function run() {
+    try {
+        const key = core.getInput("key");
+        const value = core.getInput("value");
+        const token = core.getInput("token");
+        const octokit = github.getOctokit(token);
+        const { owner, repo } = github.context.repo;
+        const path = `docs/data/${key}.json`;
+        let res = await octokit.repos.getContent({
+            owner,
+            repo,
+            path,
+        });
+        let data = null;
+        const isUpdate = res.status == 200;
+        if (res.status == 404) {
+            core.info(`Found new key "${key}", will create new file.`);
+            data = { key, type: "scalar", values: [] };
+        }
+        else if (isUpdate) {
+            core.info(`Extending existing metrics for "${key}"`);
+            data = JSON.parse(fromBase64(res.data.content));
+        }
+        if (data == null) {
+            throw new Error(`Loading or updating data for "${key}" has failed`);
+        }
+        data.values.push({
+            value: Number.parseFloat(value),
+            isoDate: new Date().toISOString(),
+        });
+        const content = toBase64(JSON.stringify(data));
+        const updateRes = await octokit.repos.createOrUpdateFileContents({
+            owner,
+            repo,
+            path,
+            content,
+            sha: isUpdate ? res.data.sha : undefined,
+            message: isUpdate ? "Updated metrics" : "Created metrics",
+        });
+        core.info("Finished processing new metrics");
+    }
+    catch (error) {
+        core.setFailed(error.message);
+    }
+}
+function fromBase64(content) {
+    return Buffer.from(content, "base64").toString("ascii");
+}
+function toBase64(content) {
+    return Buffer.from(content).toString("base64");
+}
+run();
diff --git a/index.ts b/index.ts
deleted file mode 100644
index 5c35f38..0000000
--- a/index.ts
+++ /dev/null
@@ -1,40 +0,0 @@
-import * as core from "@actions/core";
-import * as github from "@actions/github";
-
-async function run() {
-  try {
-    const token = core.getInput("token");
-    const octokit = github.getOctokit(token);
-    const { owner, repo } = github.context.repo;
-    const path = "docs/index.html";
-
-    let res = await octokit.repos.getContent({
-      owner,
-      repo,
-      path,
-    });
-
-    const decodedContent = fromBase64(res.data.content);
-    const content = toBase64(`${decodedContent} <!-- Just a comment -->`);
-
-    await octokit.repos.createOrUpdateFileContents({
-      owner,
-      repo,
-      path,
-      content,
-      sha: res.data.sha,
-      message: "Updated metrics",
-    });
-  } catch (error) {
-    core.setFailed(error.message);
-  }
-}
-
-function fromBase64(content: string) {
-  return Buffer.from(content, "base64").toString("ascii");
-}
-
-function toBase64(content: string) {
-  return Buffer.from(content).toString("base64");
-}
-run();
diff --git a/package.json b/package.json
index f3a9bbf..fae64d1 100644
--- a/package.json
+++ b/package.json
@@ -6,7 +6,7 @@
   "author": "Florian Richter <floririchte@gmail.com>",
   "license": "MIT",
   "scripts": {
-    "build": "tsc ./index.ts"
+    "build": "tsc"
   },
   "dependencies": {
     "@actions/core": "^1.2.4",
diff --git a/src/index.ts b/src/index.ts
new file mode 100644
index 0000000..38b3534
--- /dev/null
+++ b/src/index.ts
@@ -0,0 +1,71 @@
+import * as core from "@actions/core";
+import * as github from "@actions/github";
+
+type MetricsValue<T> = {
+  value: T;
+  isoDate: string;
+};
+
+type MetricsData = {
+  key: string;
+  type: "scalar";
+  values: Array<MetricsValue<number>>;
+};
+
+async function run() {
+  try {
+    const key = core.getInput("key");
+    const value = core.getInput("value");
+    const token = core.getInput("token");
+    const octokit = github.getOctokit(token);
+    const { owner, repo } = github.context.repo;
+    const path = `docs/data/${key}.json`;
+
+    let res = await octokit.repos.getContent({
+      owner,
+      repo,
+      path,
+    });
+    let data: MetricsData | null = null;
+    const isUpdate = res.status == 200;
+    if (res.status == 404) {
+      core.info(`Found new key "${key}", will create new file.`);
+      data = { key, type: "scalar", values: [] };
+    } else if (isUpdate) {
+      core.info(`Extending existing metrics for "${key}"`);
+      data = JSON.parse(fromBase64(res.data.content));
+    }
+
+    if (data == null) {
+      throw new Error(`Loading or updating data for "${key}" has failed`);
+    }
+
+    data.values.push({
+      value: Number.parseFloat(value),
+      isoDate: new Date().toISOString(),
+    });
+
+    const content = toBase64(JSON.stringify(data));
+
+    const updateRes = await octokit.repos.createOrUpdateFileContents({
+      owner,
+      repo,
+      path,
+      content,
+      sha: isUpdate ? res.data.sha : undefined,
+      message: isUpdate ? "Updated metrics" : "Created metrics",
+    });
+    core.info("Finished processing new metrics");
+  } catch (error) {
+    core.setFailed(error.message);
+  }
+}
+
+function fromBase64(content: string) {
+  return Buffer.from(content, "base64").toString("ascii");
+}
+
+function toBase64(content: string) {
+  return Buffer.from(content).toString("base64");
+}
+run();
diff --git a/tsconfig.json b/tsconfig.json
index 84ae618..eecd4b8 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,5 +1,6 @@
 {
   "compilerOptions": {
+    "outDir": "./dist",
     "lib": ["es2020"],
     "module": "commonjs",
     "target": "es2019"