diff --git a/src/inc/workers.php b/src/inc/workers.php
new file mode 100644
index 0000000..6c6e1d9
--- /dev/null
+++ b/src/inc/workers.php
@@ -0,0 +1,171 @@
+<?php
+class workers {
+  const AFFILIATION_STATUS_NOTWORKING = 0;
+  const AFFILIATION_STATUS_WORKING = 1;
+  const AFFILIATION_STATUS_AUTO_NOTWORKING = 2;
+  const AFFILIATION_STATUS_AUTO_WORKING = 3;
+
+  public static $affiliationStatuses = [self::AFFILIATION_STATUS_NOTWORKING, self::AFFILIATION_STATUS_WORKING, self::AFFILIATION_STATUS_AUTO_NOTWORKING, self::AFFILIATION_STATUS_AUTO_WORKING];
+  public static $affiliationStatusesNotWorking = [self::AFFILIATION_STATUS_NOTWORKING, self::AFFILIATION_STATUS_AUTO_NOTWORKING];
+  public static $affiliationStatusesWorking = [self::AFFILIATION_STATUS_WORKING, self::AFFILIATION_STATUS_AUTO_WORKING];
+  public static $affiliationStatusesAutomatic = [self::AFFILIATION_STATUS_AUTO_WORKING, self::AFFILIATION_STATUS_AUTO_NOTWORKING];
+  public static $affiliationStatusesManual = [self::AFFILIATION_STATUS_WORKING, self::AFFILIATION_STATUS_NOTWORKING];
+
+  private static $return = "w.id id, w.person person, w.company company, c.name companyname, p.name name, p.dni dni";
+
+  public static function get($id) {
+    global $con;
+
+    $sid = (int)$id;
+
+    $query = mysqli_query($con, "SELECT ".self::$return."
+      FROM workers w
+      LEFT JOIN companies c ON w.company = c.id
+      LEFT JOIN people p ON w.person = p.id
+      WHERE w.id = $sid");
+
+    if (!mysqli_num_rows($query)) return false;
+
+    return mysqli_fetch_assoc($query);
+  }
+
+  public static function sqlAddonToGetStatusAttribute($id) {
+    $sid = (int)$id;
+
+    return "LEFT JOIN workhistory h ON w.id = h.worker
+    WHERE
+      w.person = $sid AND
+      (
+        (
+          SELECT COUNT(*)
+          FROM workhistory
+          WHERE worker = w.id AND day <= UNIX_TIMESTAMP()
+          LIMIT 1
+        ) = 0 OR
+
+        h.id = (
+          SELECT id
+          FROM workhistory
+          WHERE worker = w.id AND day <= UNIX_TIMESTAMP()
+          ORDER BY day DESC
+          LIMIT 1
+        )
+      )";
+  }
+
+  public static function getPersonWorkers($person, $simplify = false) {
+    global $con;
+
+    $query = mysqli_query($con, "SELECT ".($simplify ? "w.id id" : self::$return).", h.status status, h.day lastupdated
+      FROM workers w
+      LEFT JOIN companies c ON w.company = c.id
+      LEFT JOIN people p ON w.person = p.id
+      ".self::sqlAddonToGetStatusAttribute($person)."
+      ORDER BY
+        w.id ASC");
+
+    $results = [];
+
+    while ($row = mysqli_fetch_assoc($query)) {
+      $row["hidden"] = self::isHidden($row["status"]);
+      $results[] = ($simplify ? $row["id"] : $row);
+    }
+
+    return $results;
+  }
+
+  public static function isHidden($status) {
+    return (in_array($status, self::$affiliationStatusesWorking) ? 0 : 1);
+  }
+
+  public static function affiliationStatusHelper($status) {
+    return (self::isHidden($status) ? "Baja" : "Alta");
+  }
+
+  public static function affiliationStatusIcon($status) {
+    return (self::isHidden($status) ? "work_off" : "work");
+  }
+
+  public static function isAutomaticAffiliation($status) {
+    return in_array($status, self::$affiliationStatusesAutomatic);
+  }
+
+  public static function getWorkHistory($id) {
+    global $con;
+
+    $sid = (int)$id;
+
+    $query = mysqli_query($con, "SELECT * FROM workhistory WHERE worker = $sid ORDER BY day DESC");
+    if ($query === false) return false;
+
+    $items = [];
+    while ($row = mysqli_fetch_assoc($query)) {
+      $items[] = $row;
+    }
+
+    return $items;
+  }
+
+  public static function getWorkHistoryItem($id) {
+    global $con;
+
+    $sid = (int)$id;
+
+    $query = mysqli_query($con, "SELECT * FROM workhistory WHERE id = $sid");
+    if ($query === false || !mysqli_num_rows($query)) return false;
+
+    return mysqli_fetch_assoc($query);
+  }
+
+  public static function addWorkHistoryItem($id, $day, $status, $internal = false) {
+    global $con;
+
+    $sid = (int)$id;
+    $stime = (int)$day;
+    $sstatus = (int)$status;
+
+    if ((!$internal && !in_array($sstatus, self::$affiliationStatusesManual)) || ($internal && !in_array($affiliationStatuses))) return false;
+
+    if (!workers::exists($sid)) return false;
+
+    return mysqli_query($con, "INSERT INTO workhistory (worker, day, status) VALUES ($sid, $stime, $sstatus)");
+  }
+
+  public static function editWorkHistoryItem($id, $day, $status, $internal = false) {
+    global $con;
+
+    $sid = (int)$id;
+    $stime = (int)$day;
+    $sstatus = (int)$status;
+
+    if ((!$internal && !in_array($sstatus, self::$affiliationStatusesManual)) || ($internal && !in_array($affiliationStatuses))) return false;
+
+    if (!self::existsWorkHistoryItem($id)) return false;
+
+    return mysqli_query($con, "UPDATE workhistory SET day = $stime, status = $sstatus WHERE id = $sid LIMIT 1");
+  }
+
+  public static function deleteWorkHistoryItem($id) {
+    global $con;
+
+    $sid = (int)$id;
+
+    return mysqli_query($con, "DELETE FROM workhistory WHERE id = $sid LIMIT 1");
+  }
+
+  public static function exists($id) {
+    global $con;
+
+    $query = mysqli_query($con, "SELECT id FROM workers WHERE id = ".(int)$id);
+
+    return (mysqli_num_rows($query) > 0);
+  }
+
+  public static function existsWorkHistoryItem($id) {
+    global $con;
+
+    $query = mysqli_query($con, "SELECT 1 FROM workhistory WHERE id = ".(int)$id);
+
+    return (mysqli_num_rows($query) > 0);
+  }
+}