diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..4329e7b
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+/.vscode/
+/vendor/
+
+composer.lock
diff --git a/composer.json b/composer.json
new file mode 100644
index 0000000..7e6a97a
--- /dev/null
+++ b/composer.json
@@ -0,0 +1,15 @@
+{
+    "name": "yggverse/graph",
+    "description": "PHP library to build JS-less graphs",
+    "type": "library",
+    "require": {
+        "php": ">=8.1"
+    },
+    "license": "MIT",
+    "autoload": {
+        "psr-4": {
+            "Yggverse\\Graph\\": "src/"
+        }
+    },
+    "minimum-stability": "alpha"
+}
diff --git a/src/Calendar/Month.php b/src/Calendar/Month.php
new file mode 100644
index 0000000..3e51c65
--- /dev/null
+++ b/src/Calendar/Month.php
@@ -0,0 +1,79 @@
+<?php
+
+declare(strict_types=1);
+
+namespace YGGverse\Chart\Calendar;
+
+class Month
+{
+  private $_time;
+  private $_node = [];
+
+  public function __construct(int $time = null, int $calendar = CAL_GREGORIAN)
+  {
+    // Set timestamp
+    $this->_time = $time ? $time : time();
+
+    // Generate calendar days
+    for ($day = 1; $day <= cal_days_in_month($calendar, (int) date('n', $this->_time), (int) date('Y', $this->_time)); $day++)
+    {
+      $this->_node[$day][0] = [];
+    }
+  }
+
+  public function addNode(int $day, int $value, string $label = null, string $class = null, int $layer = 0)
+  {
+    $this->_node[$day][$layer][] = [
+      'value'  => $value,
+      'label'  => $label,
+      'class'  => $class,
+      'width'  => 0,
+      'height' => 0,
+      'offset' => 0,
+    ];
+  }
+
+  public function getNodes() : object
+  {
+    // Calculate month totals
+    $total = [];
+
+    foreach ($this->_node as $i => $day)
+    {
+      foreach ($day as $l => $layer)
+      {
+        $total[$i][$l] = 0;
+
+        foreach ($layer as $data)
+        {
+          $total[$i][$l] += $data['value'];
+        }
+      }
+    }
+
+    // Calculate dimensions
+    foreach ($this->_node as $i => $day)
+    {
+      foreach ($day as $l => $layer)
+      {
+        // Count data values in layer
+        $count = 0;
+        foreach ($layer as $data) $count++;
+
+        // Calculate column width
+        $width = $count ? 100 / $count : 0;
+
+        // Calculate column width, height, offset
+        foreach ($layer as $j => $data)
+        {
+          $this->_node[$i][$l][$j]['width']  = $width;
+          $this->_node[$i][$l][$j]['height'] = $total[$i][$l] ? ceil($data['value'] / $total[$i][$l] * 100) : 0;
+          $this->_node[$i][$l][$j]['offset'] = $width * $j;
+        }
+      }
+    }
+
+    // Return object
+    return json_decode(json_encode($this->_node));
+  }
+}
\ No newline at end of file