diff --git a/File.class.php b/File.class.php
index de88b00..fdb9d7e 100644
--- a/File.class.php
+++ b/File.class.php
@@ -35,8 +35,11 @@ class File {
         return $headers;
     }
 
-    function get_status($follow=true) {
-        return $this->get_headers($follow)["status"];
+    function get_status($follow=true, $throw=true) {
+        if ($status=$this->get_headers($follow)["status"] >= 400) {
+            throw new Exception("Error downloading " . $this->url . " - Status: " . $status);
+        }
+        return $status;
     }
 
     function get_filename($follow=true) {
diff --git a/Mail.class.php b/Mail.class.php
new file mode 100644
index 0000000..2613edc
--- /dev/null
+++ b/Mail.class.php
@@ -0,0 +1,95 @@
+<?php
+
+require_once 'vendor/autoload.php';
+
+use PHPMailer\PHPMailer\PHPMailer;
+use PHPMailer\PHPMailer\Exception;
+
+class Mail {
+    private $mailer;
+
+    function __construct($host=null, $user=null, $password=null, $port=null) {
+        global $MAIL_HOST, $MAIL_USER, $MAIL_PASS, $MAIL_STARTTLS, $MAIL_SMTPS, $MAIL_PORT;
+        $this->mailer = new PHPMailer(true);
+        $this->mailer->isSMTP();
+        $this->mailer->AllowEmpty = true;
+        $this->mailer->Host = $host ?: $MAIL_HOST;
+        $this->mailer->SMTPAuth = (bool) $MAIL_USER;
+        $this->mailer->Username = $user ?: $MAIL_USER;
+        $this->mailer->Password = $password ?: $MAIL_PASS;
+        $this->mailer->SMTPSecure = $MAIL_STARTTLS ? PHPMailer::ENCRYPTION_STARTTLS : ($MAIL_SMTPS ? PHPMailer::ENCRYPTION_SMTPS : false);
+        $this->mailer->Port = $port ?: ($MAIL_PORT ?: ($MAIL_SMTPS ? 465 : 587));
+        $this->mailer->XMailer = "Kumi Systems Mailer 0.1 (https://kumi.systems/)";
+    }
+
+    function add_attachment($content, $filename=null, $cid=null) {
+        $this->mailer->addStringEmbeddedImage($content, $cid, $filename);
+    }
+
+    function add_attachments($attachments) {
+        foreach ($attachments as $attachment) {
+            $this->add_attachment($attachment["content"], $attachment["filename"], $attachment["cid"]);
+        }
+    }
+
+    function add_bcc($email, $name) {
+        $this->mailer->addBCC($email, $name);
+    }
+
+    function add_bccs($bccs) {
+        foreach ($bccs as $bcc) {
+            $this->add_bcc($bcc["email"], $bcc["name"]);
+        }
+    }    
+
+    function add_cc($email, $name) {
+        $this->mailer->addCC($email, $name);
+    }
+
+    function add_ccs($ccs) {
+        foreach ($ccs as $cc) {
+            $this->add_cc($cc["email"], $cc["name"]);
+        }
+    }
+
+    function add_content($html=null, $text=null) {
+        $this->mailer->isHTML((bool) $html);
+        $this->mailer->Body = $html ?: $text;
+        $this->mailer->AltBody = $html ? $text : null;
+    }
+
+    function add_recipient($email, $name) {
+        $this->mailer->addAddress($email, $name);
+    }
+
+    function add_recipients($recipients) {
+        foreach ($recipients as $recipient) {
+            $this->add_recipient($recipient["email"], $recipient["name"]);
+        }
+    }
+
+    static function FromRequest($req) {
+        $mail = new self();
+
+        $mail->set_from($req->get_sender()["email"], $req->get_sender()["name"]);
+        $mail->add_recipients($req->get_recipients());
+        $mail->add_ccs($req->get_ccs());
+        $mail->add_bccs($req->get_bccs());
+    
+        $html = $req->prepare_html();
+        $text = $req->prepare_text(!$req->has_config("noconversion"));
+        $mail->add_content($html, $text);
+    
+        $mail->add_attachments($req->get_attachments(true, true, $req->has_config("ignoredlfails")));
+
+        return $mail;
+    }
+
+    function send() {
+        $this->mailer->send();
+    }
+
+    function set_from($email, $name) {
+        $this->mailer->setFrom($email, $name);
+    }
+}
\ No newline at end of file
diff --git a/Request.class.php b/Request.class.php
new file mode 100644
index 0000000..2aa78c8
--- /dev/null
+++ b/Request.class.php
@@ -0,0 +1,165 @@
+<?php
+
+require_once("config.php");
+require_once("File.class.php");
+
+class Request {
+    public $json;
+
+    function __construct($data, $authorize=True) {
+        if (!$json=json_decode($data, true)) {
+            throw new Exception("There is nothing here.");
+        };
+        
+        $this->json = array_change_key_case($json, CASE_LOWER);
+
+        if ($authorize) {
+            if (!$this->authorize()) {
+                throw new Exception("Who are you?");
+            }
+        }
+    }
+
+    function authorize() {
+        global $API_KEYS;
+        return in_array($this->get_key(), $API_KEYS);
+    }
+
+    function get_attachments($resolve=true, $content=true, $ignoredlfails=false) {
+        $outachments = array();
+        foreach ($this->json["attachments"] as $attachment) {
+            $attachment["content"] = "";
+            if ($resolve || $content) {
+                $file = new File($attachment["url"]);
+                if ($resolve && !$attachment["filename"]) {
+                    $attachment["filename"] = $file->get_filename();
+                }
+                if ($content) {
+                    try {
+                        $attachment["content"] = $file->fetch_file();
+                    } catch (\Exception $e) {
+                        if (!$ignoredlfails) {
+                            throw $e;
+                        }
+                    }
+                }
+            }
+            if ($attachment["content"] || !$content) {
+                array_push($outachments, $attachment);
+            }
+        }
+        return $outachments;
+    }
+
+    function get_bccs($default=true) {
+        global $ALWAYS_BCC;
+        $bccs = $this->json["bccs"] ?: array();
+        if ($default) {
+            foreach ($ALWAYS_BCC as $bcc) {
+                array_push($bccs, array("email"=>$bcc));
+            }
+        }
+        return $bccs;
+    }
+
+    function get_ccs($default=true) {
+        global $ALWAYS_CC;
+        $ccs = $this->json["ccs"] ?: array();
+        if ($default) {
+            foreach ($ALWAYS_CC as $cc) {
+                array_push($ccs, array("email"=>$cc));
+            }
+        }
+        return $ccs;
+    }
+
+    function get_config() {
+        return $this->json["config"];
+    }
+
+    function get_html() {
+        if ($this->json["html"]) {
+            $html = $this->json["html"];
+        } else if ($this->json["htmlurl"]) {
+            try {
+                $htmlfile = new File($this->json["htmlurl"]);
+                $html = $htmlfile->fetch_file();
+            } catch (\Exception $e) {
+                throw new Exception("Could not fetch URL for HTML message: " . $e->getMessage());
+            }
+        }
+
+        return $html;
+    }
+
+    function get_key() {
+        return $this->json["key"];
+    }
+
+    function get_placeholders() {
+        return $this->json["placeholders"];
+    }
+
+    function get_recipients($default=true) {
+        global $ALWAYS_TO;
+        $recipients = $this->json["recipients"] ?: array();
+        if ($default) {
+            foreach ($ALWAYS_TO as $recipient) {
+                array_push($recipients, array("email"=>$recipient));
+            }
+        }
+        return $recipients;
+    }
+
+    function get_sender($fallback=true) {
+        global $MAIL_FROM_MAIL, $MAIL_FROM_NAME, $MAIL_USER;
+        if ($this->json["sender"]) {
+            return $this->json["sender"];
+        } else if ($fallback) {
+            return array(
+                "email" => $MAIL_FROM_MAIL ? $MAIL_FROM_MAIL : $MAIL_USER,
+                "name" => $MAIL_FROM_NAME
+            );
+        }
+    }
+
+    function get_text($conversion=true) {
+        if ($this->json["text"]) {
+            $text = $this->json["text"];
+        } else if ($this->json["texturl"]) {
+            try {
+                $textfile = new File($this->json["texturl"]);
+                $text = $textfile->fetch_file();
+            } catch (\Exception $e) {
+                throw new Exception("Could not fetch URL for plain text message: " . $e->getMessage());
+            }
+        } else if ($conversion) {
+            if ($html=$this->get_html()) {
+                $text = html_entity_decode(
+                    trim(strip_tags(preg_replace('/<(head|title|style|script)[^>]*>.*?<\/\\1>/si', '', $html))),
+                    ENT_QUOTES
+                );
+            }
+        }
+
+        return $text;
+    }
+
+    function has_config($key) {
+        return in_array($key, $this->get_config());
+    }
+
+    function prepare_html() {
+        return $this->prepare_string($this->get_html());
+    }
+
+    function prepare_string($string) {
+        foreach ($this->get_placeholders() as $placeholder) $string = str_replace("{".strtoupper($placeholder["name"])."}", $placeholder["value"], $string);
+        return $string;
+    }
+
+    function prepare_text($conversion=true) {
+        return $this->prepare_string($this->get_text($conversion));
+    }
+
+}
\ No newline at end of file
diff --git a/doc/swagger.yaml b/doc/swagger.yaml
index a005175..5cdcc5e 100644
--- a/doc/swagger.yaml
+++ b/doc/swagger.yaml
@@ -1,7 +1,7 @@
 openapi: 3.0.0
 info:
   description: A simple endpoint to send email messages
-  version: '0.3'
+  version: '0.4'
   title: EXPMail
   contact:
     email: support@kumi.systems
@@ -40,6 +40,17 @@ servers:
   - url: 'https://expmail.kumi.live'
 components:
   schemas:
+    Config:
+      type: object
+      required:
+        - key
+      properties:
+        key:
+          type: string
+          description: >
+            Key of the config setting
+             * `noconversion` - Do not automatically convert HTML to plain text if no plain text message is explicitly given
+             * `ignoredlfails` - If an attachment fails to download, just leave it out and continue processing the message
     Placeholder:
       type: object
       required:
@@ -89,10 +100,10 @@ components:
           description: Subject of the email
         html:
           type: string
-          description: 'String containing the HTML content of the email. Takes precedence over `htmlurl` if provided. If both `html` and `text` or `texturl` are provided, will create a multi-part MIME message.'
+          description: 'String containing the HTML content of the email. Takes precedence over `htmlurl` if provided. If both `html` and `text` or `texturl` are provided, or the `noconversion` config key is not provided, will create a multi-part MIME message.'
         htmlurl:
           type: string
-          description: 'String containing the URL to a file containing the HTML content of the email. Ignored if `html` if provided. If both `htmlurl` and `text` or `texturl` are provided, will create a multi-part MIME message.'
+          description: 'String containing the URL to a file containing the HTML content of the email. Ignored if `html` if provided. If both `htmlurl` and `text` or `texturl` are provided, or the `noconversion` config key is not provided, will create a multi-part MIME message.'
         text:
           type: string
           description: 'String containing the plain text content of the email. Takes precedence over `texturl` if provided. If both `text` and `html` or `htmlurl` are provided, will create a multi-part MIME message.'
@@ -128,6 +139,11 @@ components:
           description: 'Array of `Placeholder` objects. Any occurrences of `{PLACEHOLDER_NAME}` (`name` in all caps enclosed with curly brackets) in the email''s HTML or plain text will be replaced by `value`.'
           items:
             $ref: '#/components/schemas/Placeholder'
+        config:
+          type: array
+          description: 'Array of `Config` objects to change the endpoint\'s default behaviour'
+          items:
+            $ref: '#/components/schemas/Config'
         key:
           type: string
           description: API key to authenticate request with
diff --git a/sender.php b/sender.php
index 5bb9294..0b221bb 100644
--- a/sender.php
+++ b/sender.php
@@ -1,86 +1,13 @@
 <?php
 
-require_once 'vendor/autoload.php';
 require_once 'config.php';
-require_once 'File.class.php';
-
-use PHPMailer\PHPMailer\PHPMailer;
-use PHPMailer\PHPMailer\Exception;
-
-$mailer = new PHPMailer(true);
+require_once 'Mail.class.php';
+require_once 'Request.class.php';
 
 try {
-    if (!$json = json_decode(file_get_contents('php://input'), true)) throw new Exception("There is nothing here.");
-
-    if (!$json["key"]) throw new Exception("What's the code word?");
-
-    if (!in_array($json["key"], $API_KEYS)) throw new Exception("Who are you?");
-
-    if ($json["html"]) {
-        $html = $json["html"];
-    } else if ($json["htmlurl"]) {
-        try {
-            $htmlfile = new File($json["htmlurl"]);
-            $html = $htmlfile->fetch_file();
-        } catch (\Exception $e) {
-            throw new Exception("Could not fetch URL for HTML message: " . $e->getMessage());
-        }
-    }
-
-    if ($json["text"]) {
-        $text = $json["text"];
-    } else if ($json["texturl"]) {
-        try {
-            $textfile = new File($json["texturl"]);
-            $text = $textfile->fetch_file();
-        } catch (\Exception $e) {
-            throw new Exception("Could not fetch URL for plain text message: " . $e->getMessage());
-        }
-    }
-
-    foreach ($json["placeholders"] as $placeholder) {
-        $html = str_replace("{".strtoupper($placeholder["name"])."}", $placeholder["value"], $html);
-        $text = str_replace("{".strtoupper($placeholder["name"])."}", $placeholder["value"], $text);
-    }
-
-    $mailer->isSMTP();
-    $mailer->Host = $MAIL_HOST;
-    $mailer->SMTPAuth = (bool) $MAIL_USER;
-    $mailer->Username = $MAIL_USER;
-    $mailer->Password = $MAIL_PASS;
-    $mailer->SMTPSecure = ($MAIL_STARTTLS ? PHPMailer::ENCRYPTION_STARTTLS : ($MAIL_SMTPS ? PHPMailer::ENCRYPTION_SMTPS : false));
-    $mailer->Port = ($MAIL_PORT ? $MAIL_PORT : ($MAIL_SMTPS ? 465 : 587));
-    $mailer->XMailer = "Kumi Systems Mailer 0.1 (https://kumi.systems/)";
-
-    if ($json["sender"]["email"]) {
-        $mailer->setFrom($json["sender"]["email"], $json["sender"]["name"]);
-    } else {
-        $mailer->setFrom(($MAIL_FROM_MAIL ? $MAIL_FROM_MAIL : $MAIL_USER), $MAIL_FROM_NAME);
-    };
-
-    foreach ($json["recipients"] as $recipient) $mailer->addAddress($recipient["email"], $recipient["name"]);
-    foreach ($json["ccs"] as $cc) $mailer->addCC($cc["email"], $cc["name"]);
-    foreach ($json["bccs"] as $bcc) $mailer->addBCC($bcc["email"], $bcc["name"]);
-
-    foreach ($ALWAYS_TO as $recipient) $mailer->addAddress($recipient);
-    foreach ($ALWAYS_CC as $cc) $mailer->addCC($cc);
-    foreach ($ALWAYS_BCC as $bcc) $mailer->addBCC($bcc);
-
-    $mailer->isHTML((bool) $html);
-    $mailer->Subject = $json["subject"];
-    $mailer->Body = ($html ? $html : $text);
-    $mailer->AltBody = ($html ? $text : null);
-
-    foreach ($json["attachments"] as $attachment) {
-        $file = new File($attachment["url"]);
-        if ($file->get_status() >= 400) throw new Exception("Error downloading " . $attachment["url"] . " - Status: " . $file->get_status());
-        $content = $file->fetch_file();
-        $filename = ($attachment["filename"] ? $attachment["filename"] : $file->get_filename());
-        $cid = ($attachment["cid"] ? $attachment["cid"] : 0);
-        $mailer->addStringEmbeddedImage($content, $cid, $filename);
-    }
-
-    $mailer->send();
+    $req = new Request(file_get_contents('php://input'));
+    $mail = Mail::FromRequest($req);
+    $mail->send();
 
     $response = array(
         "status" => "success"