From fb719c36fea5ab1d653337a1c452618fc4cc0c8b Mon Sep 17 00:00:00 2001
From: me <me@fymio.us>
Date: Wed, 18 Feb 2026 23:02:55 +0300
Subject: [PATCH] add 'Spring Boot' course

---
 content/courses/spring-boot/_index.md         |  36 ++
 .../spring-boot/assets/spring-layers.svg      |   1 +
 public/categories/index.html                  |   8 +
 public/courses/index.html                     |  17 +-
 public/courses/paradigms/index.html           |  15 +
 .../courses/prog-intro/homeworks/index.html   |  17 +-
 public/courses/prog-intro/index.html          |  17 +-
 public/courses/prog-intro/lectures/index.html |  17 +-
 .../prog-intro/lectures/intro/index.html      |  10 +-
 .../spring-boot/assets/spring-layers.svg      |   1 +
 .../spring-boot/assets/spring-modules.svg     |   1 +
 public/courses/spring-boot/index.html         | 417 ++++++++++++++++++
 public/courses/spring-boot/index.xml          |  18 +
 public/en.search-data.json                    |   2 +-
 public/index.html                             |   8 +
 public/sitemap.xml                            |   2 +
 public/tags/index.html                        |   8 +
 17 files changed, 589 insertions(+), 6 deletions(-)
 create mode 100644 content/courses/spring-boot/_index.md
 create mode 100644 content/courses/spring-boot/assets/spring-layers.svg
 create mode 100644 public/courses/spring-boot/assets/spring-layers.svg
 create mode 100644 public/courses/spring-boot/assets/spring-modules.svg
 create mode 100644 public/courses/spring-boot/index.html
 create mode 100644 public/courses/spring-boot/index.xml

diff --git a/content/courses/spring-boot/_index.md b/content/courses/spring-boot/_index.md
new file mode 100644
index 0000000..f7baa74
--- /dev/null
+++ b/content/courses/spring-boot/_index.md
@@ -0,0 +1,36 @@
+---
+# title: Courses
+weight: 3
+---
+
+# Prerequisites
+
+* Solid understanding of Java
+* Object-oriented programming
+* Classes, methods and interfaces
+* Basic understanding of databases
+* Tables, primary keys, foreign keys, relationships, etc.
+* Write basic SQL statements
+
+--- 
+
+# What is a Spring Framework?
+
+**Spring** -- is a popular framework for building Java applications. It has a lot of modules, each designed to handle a specific task. They are combined into few different layers.
+
+![Spring layers](assets/spring-layers.svg) 
+*Img. 1 -- Spring layers*
+
+| **Layer** | **Purpose** |
+| ------------- | -------------- | 
+| *Core* | Handling dependency injection, managing objects |
+| *Web* | Building web applications |
+| *Data* | Working with databases |
+| *AOP* | Aspect oriented programming |
+| *Test* | Testing spring components |
+
+--- 
+
+While the spring framework is powerfull, using it often involves a lot of configuration. For example, if you want to build a web app you might need to setup a web server, configure routing and manage dependencies manually. That's when **Spring Boot** comes in.
+
+You can think of spring boot as a layer on top of the spring framework, that takes care of all of the setup.
diff --git a/content/courses/spring-boot/assets/spring-layers.svg b/content/courses/spring-boot/assets/spring-layers.svg
new file mode 100644
index 0000000..c49808d
--- /dev/null
+++ b/content/courses/spring-boot/assets/spring-layers.svg
@@ -0,0 +1 @@
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diff --git a/public/categories/index.html b/public/categories/index.html
index 961d659..dcaeaa7 100644
--- a/public/categories/index.html
+++ b/public/categories/index.html
@@ -157,6 +157,14 @@
         <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
     href="/courses/prog-intro/"
     
   >Introduction to Programming in Java
diff --git a/public/courses/index.html b/public/courses/index.html
index be79047..399d8ff 100644
--- a/public/courses/index.html
+++ b/public/courses/index.html
@@ -84,7 +84,7 @@
   title=""
   href="/courses"
   
-  class="hx:text-sm hx:contrast-more:text-gray-700 hx:contrast-more:dark:text-gray-100 hx:relative hx:-ml-2 hx:hidden hx:whitespace-nowrap hx:p-2 hx:md:inline-flex hx:items-center hx:gap-1 hx:text-gray-600 hx:hover:text-gray-800 hx:dark:text-gray-400 hx:dark:hover:text-gray-200"
+  class="hx:text-sm hx:contrast-more:text-gray-700 hx:contrast-more:dark:text-gray-100 hx:relative hx:-ml-2 hx:hidden hx:whitespace-nowrap hx:p-2 hx:md:inline-flex hx:items-center hx:gap-1 hx:font-medium"
 ><span class="hx:text-center">Courses</span>
 </a><div class="hextra-search-wrapper hx:relative hx:md:w-64">
   <div class="hx:relative hx:flex hx:items-center hx:text-gray-900 hx:contrast-more:text-gray-800 hx:dark:text-gray-300 hx:contrast-more:dark:text-gray-300">
@@ -158,6 +158,14 @@
         <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
     href="/courses/prog-intro/"
     
   >Introduction to Programming in Java
@@ -210,6 +218,13 @@
           <li class=""><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a></li>
+          <li class=""><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
     href="/courses/prog-intro/"
     
   >Introduction to Programming in Java
diff --git a/public/courses/paradigms/index.html b/public/courses/paradigms/index.html
index 0054d55..872d2ed 100644
--- a/public/courses/paradigms/index.html
+++ b/public/courses/paradigms/index.html
@@ -157,6 +157,14 @@
         <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
     href="/courses/prog-intro/"
     
   >Introduction to Programming in Java
@@ -210,6 +218,13 @@
           <li class=""><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a></li>
+          <li class=""><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
     href="/courses/prog-intro/"
     
   >Introduction to Programming in Java
diff --git a/public/courses/prog-intro/homeworks/index.html b/public/courses/prog-intro/homeworks/index.html
index d0bb795..7697cb9 100644
--- a/public/courses/prog-intro/homeworks/index.html
+++ b/public/courses/prog-intro/homeworks/index.html
@@ -154,7 +154,15 @@
   >Courses
         <span class="hextra-sidebar-collapsible-button"><svg fill="none" viewBox="0 0 24 24" stroke="currentColor" class="hx:h-[18px] hx:min-w-[18px] hx:rounded-xs hx:p-0.5 hx:hover:bg-gray-800/5 hx:dark:hover:bg-gray-100/5"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 5l7 7-7 7" class="hx:origin-center hx:transition-transform hx:rtl:-rotate-180"></path></svg></span>
     </a><div class="hx:ltr:pr-0 hx:overflow-hidden">
-        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col open"><a
+        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col open"><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
     href="/courses/prog-intro/"
@@ -207,6 +215,13 @@
 
     <ul class="hx:flex hx:flex-col hx:gap-1 hx:max-md:hidden">
         
+          <li class=""><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a></li>
           <li class="open"><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
diff --git a/public/courses/prog-intro/index.html b/public/courses/prog-intro/index.html
index ca9144e..02f8a13 100644
--- a/public/courses/prog-intro/index.html
+++ b/public/courses/prog-intro/index.html
@@ -154,7 +154,15 @@
   >Courses
         <span class="hextra-sidebar-collapsible-button"><svg fill="none" viewBox="0 0 24 24" stroke="currentColor" class="hx:h-[18px] hx:min-w-[18px] hx:rounded-xs hx:p-0.5 hx:hover:bg-gray-800/5 hx:dark:hover:bg-gray-100/5"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 5l7 7-7 7" class="hx:origin-center hx:transition-transform hx:rtl:-rotate-180"></path></svg></span>
     </a><div class="hx:ltr:pr-0 hx:overflow-hidden">
-        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col open"><a
+        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col open"><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hextra-sidebar-active-item hx:bg-primary-100 hx:font-semibold hx:text-primary-800 hx:contrast-more:border hx:contrast-more:border-primary-500 hx:dark:bg-primary-400/10 hx:dark:text-primary-600 hx:contrast-more:dark:border-primary-500"
     href="/courses/prog-intro/"
@@ -207,6 +215,13 @@
 
     <ul class="hx:flex hx:flex-col hx:gap-1 hx:max-md:hidden">
         
+          <li class=""><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a></li>
           <li class="open"><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hextra-sidebar-active-item hx:bg-primary-100 hx:font-semibold hx:text-primary-800 hx:contrast-more:border hx:contrast-more:border-primary-500 hx:dark:bg-primary-400/10 hx:dark:text-primary-600 hx:contrast-more:dark:border-primary-500"
diff --git a/public/courses/prog-intro/lectures/index.html b/public/courses/prog-intro/lectures/index.html
index 4de1697..82f5535 100644
--- a/public/courses/prog-intro/lectures/index.html
+++ b/public/courses/prog-intro/lectures/index.html
@@ -154,7 +154,15 @@
   >Courses
         <span class="hextra-sidebar-collapsible-button"><svg fill="none" viewBox="0 0 24 24" stroke="currentColor" class="hx:h-[18px] hx:min-w-[18px] hx:rounded-xs hx:p-0.5 hx:hover:bg-gray-800/5 hx:dark:hover:bg-gray-100/5"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 5l7 7-7 7" class="hx:origin-center hx:transition-transform hx:rtl:-rotate-180"></path></svg></span>
     </a><div class="hx:ltr:pr-0 hx:overflow-hidden">
-        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col open"><a
+        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col open"><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
     href="/courses/prog-intro/"
@@ -207,6 +215,13 @@
 
     <ul class="hx:flex hx:flex-col hx:gap-1 hx:max-md:hidden">
         
+          <li class=""><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a></li>
           <li class="open"><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
diff --git a/public/courses/prog-intro/lectures/intro/index.html b/public/courses/prog-intro/lectures/intro/index.html
index f7e1509..af583a4 100644
--- a/public/courses/prog-intro/lectures/intro/index.html
+++ b/public/courses/prog-intro/lectures/intro/index.html
@@ -182,7 +182,15 @@ It’s fairly easy It has a broad spectre of usage Server Desktop Mobile devices
   >Courses
         <span class="hextra-sidebar-collapsible-button"><svg fill="none" viewBox="0 0 24 24" stroke="currentColor" class="hx:h-[18px] hx:min-w-[18px] hx:rounded-xs hx:p-0.5 hx:hover:bg-gray-800/5 hx:dark:hover:bg-gray-100/5"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 5l7 7-7 7" class="hx:origin-center hx:transition-transform hx:rtl:-rotate-180"></path></svg></span>
     </a><div class="hx:ltr:pr-0 hx:overflow-hidden">
-        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col open"><a
+        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col open"><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
     href="/courses/prog-intro/"
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diff --git a/public/courses/spring-boot/assets/spring-modules.svg b/public/courses/spring-boot/assets/spring-modules.svg
new file mode 100644
index 0000000..c49808d
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diff --git a/public/courses/spring-boot/index.html b/public/courses/spring-boot/index.html
new file mode 100644
index 0000000..bf05b9c
--- /dev/null
+++ b/public/courses/spring-boot/index.html
@@ -0,0 +1,417 @@
+<!DOCTYPE html>
+<html lang="en" dir="ltr"><head><script src="/livereload.js?mindelay=10&amp;v=2&amp;port=1313&amp;path=livereload" data-no-instant defer></script>
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+<title>CodeJava</title>
+  <meta name="description" content="Prerequisites Solid understanding of Java Object-oriented programming Classes, methods and interfaces Basic understanding of databases Tables, primary keys, foreign keys, relationships, etc. Write basic SQL statements What is a Spring Framework?Spring – is a popular framework for building Java applications. It has a lot of modules, each designed to handle a specific task. They are combined into few different layers.
+Img. 1 – Spring layers
+Layer Purpose Core Handling dependency injection, managing objects Web Building web applications Data Working with databases AOP Aspect oriented programming Test Testing spring components While the spring framework is powerfull, using it often involves a lot of configuration. For example, if you want to build a web app you might need to setup a web server, configure routing and manage dependencies manually. That’s when Spring Boot comes in." /><link rel="canonical" href="http://localhost:1313/courses/spring-boot/" itemprop="url" />
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+  <meta itemprop="name" content="CodeJava">
+  <meta itemprop="description" content="Prerequisites Solid understanding of Java Object-oriented programming Classes, methods and interfaces Basic understanding of databases Tables, primary keys, foreign keys, relationships, etc. Write basic SQL statements What is a Spring Framework?Spring – is a popular framework for building Java applications. It has a lot of modules, each designed to handle a specific task. They are combined into few different layers.
+Img. 1 – Spring layers
+Layer Purpose Core Handling dependency injection, managing objects Web Building web applications Data Working with databases AOP Aspect oriented programming Test Testing spring components While the spring framework is powerfull, using it often involves a lot of configuration. For example, if you want to build a web app you might need to setup a web server, configure routing and manage dependencies manually. That’s when Spring Boot comes in.">
+  <meta itemprop="wordCount" content="156">
+  <meta name="twitter:card" content="summary">
+  <meta name="twitter:title" content="CodeJava">
+  <meta name="twitter:description" content="Prerequisites Solid understanding of Java Object-oriented programming Classes, methods and interfaces Basic understanding of databases Tables, primary keys, foreign keys, relationships, etc. Write basic SQL statements What is a Spring Framework?Spring – is a popular framework for building Java applications. It has a lot of modules, each designed to handle a specific task. They are combined into few different layers.
+Img. 1 – Spring layers
+Layer Purpose Core Handling dependency injection, managing objects Web Building web applications Data Working with databases AOP Aspect oriented programming Test Testing spring components While the spring framework is powerfull, using it often involves a lot of configuration. For example, if you want to build a web app you might need to setup a web server, configure routing and manage dependencies manually. That’s when Spring Boot comes in.">
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+      class="hx:absolute hx:my-1.5 hx:select-none hx:ltr:right-1.5 hx:rtl:left-1.5 hx:h-5 hx:rounded-sm hx:bg-white hx:px-1.5 hx:font-mono hx:text-[10px] hx:font-medium hx:text-gray-500 hx:border hx:border-gray-200 hx:dark:border-gray-100/20 hx:dark:bg-dark/50 hx:contrast-more:border-current hx:contrast-more:text-current hx:contrast-more:dark:border-current hx:items-center hx:gap-1 hx:transition-opacity hx:pointer-events-none hx:hidden hx:sm:flex"
+    >
+      CTRL K
+    </kbd>
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+    <ul
+      class="hextra-search-results hextra-scrollbar hx:hidden hx:border hx:border-gray-200 hx:bg-white hx:text-gray-100 hx:dark:border-neutral-800 hx:dark:bg-neutral-900 hx:absolute hx:top-full hx:z-20 hx:mt-2 hx:overflow-auto hx:overscroll-contain hx:rounded-xl hx:py-2.5 hx:shadow-xl hx:max-h-[min(calc(50vh-11rem-env(safe-area-inset-bottom)),400px)] hx:md:max-h-[min(calc(100vh-5rem-env(safe-area-inset-bottom)),400px)] hx:inset-x-0 hx:ltr:md:left-auto hx:rtl:md:right-auto hx:contrast-more:border hx:contrast-more:border-gray-900 hx:contrast-more:dark:border-gray-50 hx:w-screen hx:min-h-[100px] hx:max-w-[min(calc(100vw-2rem),calc(100%+20rem))]"
+      style="transition: max-height 0.2s ease 0s;"
+    ></ul>
+  </div>
+</div>
+
+  </div>
+  <div class="hextra-scrollbar hx:overflow-y-auto hx:overflow-x-hidden hx:p-4 hx:grow hx:md:h-[calc(100vh-var(--navbar-height)-var(--menu-height))]">
+    <ul class="hx:flex hx:flex-col hx:gap-1 hx:md:hidden">
+      
+      
+          <li class="open"><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/"
+    
+  >Courses
+        <span class="hextra-sidebar-collapsible-button"><svg fill="none" viewBox="0 0 24 24" stroke="currentColor" class="hx:h-[18px] hx:min-w-[18px] hx:rounded-xs hx:p-0.5 hx:hover:bg-gray-800/5 hx:dark:hover:bg-gray-100/5"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 5l7 7-7 7" class="hx:origin-center hx:transition-transform hx:rtl:-rotate-180"></path></svg></span>
+    </a><div class="hx:ltr:pr-0 hx:overflow-hidden">
+        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col open"><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hextra-sidebar-active-item hx:bg-primary-100 hx:font-semibold hx:text-primary-800 hx:contrast-more:border hx:contrast-more:border-primary-500 hx:dark:bg-primary-400/10 hx:dark:text-primary-600 hx:contrast-more:dark:border-primary-500"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a>
+  
+    <ul class='hx:flex hx:flex-col hx:gap-1 hx:relative hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:dark:before:bg-neutral-800 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:pr-3 hx:rtl:before:right-0 hx:ltr:ml-3 hx:rtl:mr-3'></ul>
+  
+              
+            </li><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/prog-intro/"
+    
+  >Introduction to Programming in Java
+        <span class="hextra-sidebar-collapsible-button"><svg fill="none" viewBox="0 0 24 24" stroke="currentColor" class="hx:h-[18px] hx:min-w-[18px] hx:rounded-xs hx:p-0.5 hx:hover:bg-gray-800/5 hx:dark:hover:bg-gray-100/5"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 5l7 7-7 7" class="hx:origin-center hx:transition-transform hx:rtl:-rotate-180"></path></svg></span>
+    </a>
+              <div class="hx:ltr:pr-0 hx:overflow-hidden">
+        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/prog-intro/homeworks/"
+    
+  >Homeworks
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/prog-intro/lectures/"
+    
+  >Lectures
+        <span class="hextra-sidebar-collapsible-button"><svg fill="none" viewBox="0 0 24 24" stroke="currentColor" class="hx:h-[18px] hx:min-w-[18px] hx:rounded-xs hx:p-0.5 hx:hover:bg-gray-800/5 hx:dark:hover:bg-gray-100/5"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 5l7 7-7 7" class="hx:origin-center hx:transition-transform hx:rtl:-rotate-180"></path></svg></span>
+    </a>
+              <div class="hx:ltr:pr-0 hx:overflow-hidden">
+        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/prog-intro/lectures/intro/"
+    
+  >Lecture 1. Introduction
+    </a>
+              
+            </li></ul>
+      </div>
+            </li></ul>
+      </div>
+            </li><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/paradigms/"
+    
+  >Paradgims of Programming
+    </a>
+              
+            </li></ul>
+      </div></li>
+    </ul>
+
+    <ul class="hx:flex hx:flex-col hx:gap-1 hx:max-md:hidden">
+        
+          <li class="open"><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hextra-sidebar-active-item hx:bg-primary-100 hx:font-semibold hx:text-primary-800 hx:contrast-more:border hx:contrast-more:border-primary-500 hx:dark:bg-primary-400/10 hx:dark:text-primary-600 hx:contrast-more:dark:border-primary-500"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a></li>
+          <li class=""><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/prog-intro/"
+    
+  >Introduction to Programming in Java
+        <span class="hextra-sidebar-collapsible-button"><svg fill="none" viewBox="0 0 24 24" stroke="currentColor" class="hx:h-[18px] hx:min-w-[18px] hx:rounded-xs hx:p-0.5 hx:hover:bg-gray-800/5 hx:dark:hover:bg-gray-100/5"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 5l7 7-7 7" class="hx:origin-center hx:transition-transform hx:rtl:-rotate-180"></path></svg></span>
+    </a><div class="hx:ltr:pr-0 hx:overflow-hidden">
+        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/prog-intro/homeworks/"
+    
+  >Homeworks
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/prog-intro/lectures/"
+    
+  >Lectures
+        <span class="hextra-sidebar-collapsible-button"><svg fill="none" viewBox="0 0 24 24" stroke="currentColor" class="hx:h-[18px] hx:min-w-[18px] hx:rounded-xs hx:p-0.5 hx:hover:bg-gray-800/5 hx:dark:hover:bg-gray-100/5"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 5l7 7-7 7" class="hx:origin-center hx:transition-transform hx:rtl:-rotate-180"></path></svg></span>
+    </a>
+              <div class="hx:ltr:pr-0 hx:overflow-hidden">
+        <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/prog-intro/lectures/intro/"
+    
+  >Lecture 1. Introduction
+    </a>
+              
+            </li></ul>
+      </div>
+            </li></ul>
+      </div></li>
+          <li class=""><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/paradigms/"
+    
+  >Paradgims of Programming
+    </a></li>
+        
+      </ul>
+    </div>
+  
+  
+    <div class="  hx:sticky hx:bottom-0 hx:max-h-(--menu-height) hx:bg-white hx:dark:bg-dark hx:mx-4 hx:py-4 hx:shadow-[0_-12px_16px_#fff] hx:flex hx:items-center hx:gap-2 hx:border-gray-200 hx:dark:border-neutral-800 hx:dark:shadow-[0_-12px_16px_#111] hx:contrast-more:border-neutral-400 hx:contrast-more:shadow-none hx:contrast-more:dark:shadow-none hx:border-t" data-toggle-animation="show"><div class="hx:flex hx:grow hx:flex-col"><div class="hx:flex hx:justify-items-start hx:group" data-theme="light">
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+    <div class="hx:flex hx:items-center hx:gap-2 hx:capitalize"><svg height=12 class="hx:group-data-[theme=dark]:hidden hx:group-data-[theme=system]:hidden" xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="2" stroke="currentColor" aria-hidden="true"><path stroke-linecap="round" stroke-linejoin="round" d="M12 3v1m0 16v1m9-9h-1M4 12H3m15.364 6.364l-.707-.707M6.343 6.343l-.707-.707m12.728 0l-.707.707M6.343 17.657l-.707.707M16 12a4 4 0 11-8 0 4 4 0 018 0z"/></svg><span class="hx:group-data-[theme=dark]:hidden hx:group-data-[theme=system]:hidden">Light</span><svg height=12 class="hx:group-data-[theme=light]:hidden hx:group-data-[theme=system]:hidden" xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="2" stroke="currentColor" aria-hidden="true"><path stroke-linecap="round" stroke-linejoin="round" d="M20.354 15.354A9 9 0 018.646 3.646 9.003 9.003 0 0012 21a9.003 9.003 0 008.354-5.646z"/></svg><span class="hx:group-data-[theme=light]:hidden hx:group-data-[theme=system]:hidden">Dark</span><svg height=12 class="hx:group-data-[theme=dark]:hidden hx:group-data-[theme=light]:hidden" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"  fill="currentColor">
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+</svg>
+<span class="hx:group-data-[theme=dark]:hidden hx:group-data-[theme=light]:hidden">System</span></div>
+  </button>
+  <ul
+    class="hextra-theme-toggle-options hx:hidden hx:z-20 hx:max-h-64 hx:overflow-auto hx:rounded-md hx:ring-1 hx:ring-black/5 hx:bg-white hx:py-1 hx:text-sm hx:shadow-lg hx:dark:ring-white/20 hx:dark:bg-neutral-800"
+    style="position: fixed; inset: auto auto 0px 0px; margin: 0px; min-width: 100px;"
+    data-theme="light"
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+    <li class="hx:flex hx:flex-col">
+      <p
+        data-item="light"
+        class="hx:text-gray-800 hx:dark:text-gray-100 hx:hover:bg-primary-50 hx:hover:text-primary-600 hx:hover:dark:bg-primary-500/10 hx:hover:dark:text-primary-600 hx:relative hx:cursor-pointer hx:whitespace-nowrap hx:py-1.5 hx:transition-colors hx:ltr:pl-3 hx:ltr:pr-9 hx:rtl:pr-3 hx:rtl:pl-9"
+      >
+        Light
+         <span class="hx:absolute hx:inset-y-0 hx:flex hx:items-center hx:ltr:right-3 hx:rtl:left-3 hx:group-data-[theme=dark]:hidden hx:group-data-[theme=system]:hidden"><svg height=1em width=1em xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="2" stroke="currentColor" aria-hidden="true"><path stroke-linecap="round" stroke-linejoin="round" d="M5 13l4 4L19 7"/></svg></span>
+      </p>
+    </li>
+    <li class="hx:flex hx:flex-col">
+      <p
+        data-item="dark"
+        class="hx:text-gray-800 hx:dark:text-gray-100 hx:hover:bg-primary-50 hx:hover:text-primary-600 hx:hover:dark:bg-primary-500/10 hx:hover:dark:text-primary-600 hx:relative hx:cursor-pointer hx:whitespace-nowrap hx:py-1.5 hx:transition-colors hx:ltr:pl-3 hx:ltr:pr-9 hx:rtl:pr-3 hx:rtl:pl-9"
+      >
+        Dark
+         <span class="hx:absolute hx:inset-y-0 hx:flex hx:items-center hx:ltr:right-3 hx:rtl:left-3 hx:group-data-[theme=light]:hidden hx:group-data-[theme=system]:hidden"><svg height=1em width=1em xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="2" stroke="currentColor" aria-hidden="true"><path stroke-linecap="round" stroke-linejoin="round" d="M5 13l4 4L19 7"/></svg></span>
+      </p>
+    </li>
+    <li class="hx:flex hx:flex-col">
+      <p
+        data-item="system"
+        class="hx:text-gray-800 hx:dark:text-gray-100 hx:hover:bg-primary-50 hx:hover:text-primary-600 hx:hover:dark:bg-primary-500/10 hx:hover:dark:text-primary-600 hx:relative hx:cursor-pointer hx:whitespace-nowrap hx:py-1.5 hx:transition-colors hx:ltr:pl-3 hx:ltr:pr-9 hx:rtl:pr-3 hx:rtl:pl-9"
+      >
+        System
+         <span class="hx:absolute hx:inset-y-0 hx:flex hx:items-center hx:ltr:right-3 hx:rtl:left-3 hx:group-data-[theme=dark]:hidden hx:group-data-[theme=light]:hidden"><svg height=1em width=1em xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="2" stroke="currentColor" aria-hidden="true"><path stroke-linecap="round" stroke-linejoin="round" d="M5 13l4 4L19 7"/></svg></span>
+      </p>
+    </li>
+  </ul>
+</div></div></div></aside>
+    
+<nav class="hextra-toc hx:order-last hx:hidden hx:w-64 hx:shrink-0 hx:xl:block hx:print:hidden hx:px-4" aria-label="table of contents">
+    <div class="hextra-scrollbar hx:sticky hx:top-16 hx:overflow-y-auto hx:pr-4 hx:pt-6 hx:text-sm [hyphens:auto] hx:max-h-[calc(100vh-var(--navbar-height)-env(safe-area-inset-bottom))] hx:ltr:-mr-4 hx:rtl:-ml-4"><p class="hx:mb-4 hx:font-semibold hx:tracking-tight">On this page</p><ul></ul><ul></ul>
+      <div class="hx:mt-8 hx:border-t hx:bg-white hx:pt-8 hx:shadow-[0_-12px_16px_white] hx:dark:bg-dark hx:dark:shadow-[0_-12px_16px_#111] hx:sticky hx:bottom-0 hx:flex hx:flex-col hx:items-start hx:gap-2 hx:pb-8 hx:border-gray-200 hx:dark:border-neutral-800 hx:contrast-more:border-t hx:contrast-more:border-neutral-400 hx:contrast-more:shadow-none hx:contrast-more:dark:border-neutral-400">
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+          <span>Scroll to top</span>
+          <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="1.5" stroke="currentColor" class="hx:inline hx:ltr:ml-1 hx:rtl:mr-1 hx:h-3.5 hx:w-3.5 hx:rounded-full hx:border hx:border-gray-500 hx:hover:border-gray-900 hx:dark:border-gray-400 hx:dark:hover:border-gray-100 hx:contrast-more:border-gray-800 hx:contrast-more:dark:border-gray-50">
+            <path stroke-linecap="round" stroke-linejoin="round" d="M4.5 15.75l7.5-7.5 7.5 7.5" />
+          </svg>
+        </button>
+      </div>
+    </div>
+  </nav>
+
+
+    <article class="hx:w-full hx:break-words hx:flex hx:min-h-[calc(100vh-var(--navbar-height))] hx:min-w-0 hx:justify-center hx:pb-8 hx:pr-[calc(env(safe-area-inset-right)-1.5rem)]">
+      <main class="hx:w-full hx:min-w-0 hx:max-w-6xl hx:px-6 hx:pt-4 hx:md:px-12">
+        
+        <div class="content">
+          
+          <h1>Prerequisites</h1><ul>
+<li>Solid understanding of Java</li>
+<li>Object-oriented programming</li>
+<li>Classes, methods and interfaces</li>
+<li>Basic understanding of databases</li>
+<li>Tables, primary keys, foreign keys, relationships, etc.</li>
+<li>Write basic SQL statements</li>
+</ul>
+<hr>
+<h1>What is a Spring Framework?</h1><p><strong>Spring</strong> &ndash; is a popular framework for building Java applications. It has a lot of modules, each designed to handle a specific task. They are combined into few different layers.</p>
+<p><img src="assets/spring-layers.svg" alt="Spring layers"  loading="lazy" />
+<em>Img. 1 &ndash; Spring layers</em></p>
+<table>
+  <thead>
+      <tr>
+          <th><strong>Layer</strong></th>
+          <th><strong>Purpose</strong></th>
+      </tr>
+  </thead>
+  <tbody>
+      <tr>
+          <td><em>Core</em></td>
+          <td>Handling dependency injection, managing objects</td>
+      </tr>
+      <tr>
+          <td><em>Web</em></td>
+          <td>Building web applications</td>
+      </tr>
+      <tr>
+          <td><em>Data</em></td>
+          <td>Working with databases</td>
+      </tr>
+      <tr>
+          <td><em>AOP</em></td>
+          <td>Aspect oriented programming</td>
+      </tr>
+      <tr>
+          <td><em>Test</em></td>
+          <td>Testing spring components</td>
+      </tr>
+  </tbody>
+</table>
+<hr>
+<p>While the spring framework is powerfull, using it often involves a lot of configuration. For example, if you want to build a web app you might need to setup a web server, configure routing and manage dependencies manually. That&rsquo;s when <strong>Spring Boot</strong> comes in.</p>
+<p>You can think of spring boot as a layer on top of the spring framework, that takes care of all of the setup.</p>
+
+        </div>
+        <div class="hx:mt-16"></div>
+        <div class="hx:mt-16"></div>
+        
+      </main>
+    </article>
+  </div>
+
+      <footer class="hextra-footer hx:bg-gray-100 hx:pb-[env(safe-area-inset-bottom)] hx:dark:bg-neutral-900 hx:print:bg-transparent"><div class="hextra-custom-footer hextra-max-footer-width hx:pl-[max(env(safe-area-inset-left),1.5rem)] hx:pr-[max(env(safe-area-inset-right),1.5rem)] hx:text-gray-600 hx:dark:text-gray-400"></div><div
+      class="hextra-max-footer-width hx:mx-auto hx:flex hx:justify-center hx:py-12 hx:pl-[max(env(safe-area-inset-left),1.5rem)] hx:pr-[max(env(safe-area-inset-right),1.5rem)] hx:text-gray-600 hx:dark:text-gray-400 hx:md:justify-start"
+    >
+      <div class="hx:flex hx:w-full hx:flex-col hx:items-center hx:sm:items-start"><div class="hx:font-semibold"><a class="hx:flex hx:text-sm hx:items-center hx:gap-1 hx:text-current" target="_blank" rel="noopener noreferrer" title="Hextra GitHub Homepage" href="https://github.com/imfing/hextra">
+    <span>Powered by Hextra<svg height=1em class="hx:inline-block hx:ltr:ml-1 hx:rtl:mr-1 hx:align-[-2.5px]" viewBox="0 0 180 180" xmlns="http://www.w3.org/2000/svg" fill="currentColor"><path fill-rule="evenodd" clip-rule="evenodd" d="m 105.50024,22.224647 c -9.59169,-5.537563 -21.40871,-5.537563 -31.000093,0 L 39.054693,42.689119 C 29.463353,48.226675 23.55484,58.460531 23.55484,69.535642 v 40.928918 c 0,11.07542 5.908513,21.3092 15.499853,26.84652 l 35.445453,20.46446 c 9.591313,5.53732 21.408404,5.53732 31.000094,0 l 35.44507,-20.46446 c 9.59131,-5.53732 15.49985,-15.7711 15.49985,-26.84652 V 69.535642 c 0,-11.075111 -5.90854,-21.308967 -15.49985,-26.846523 z M 34.112797,85.737639 c -1.384445,2.397827 -1.384445,5.352099 0,7.749927 l 24.781554,42.922974 c 1.38437,2.39783 3.942853,3.87496 6.711592,3.87496 h 49.563107 c 2.76905,0 5.3273,-1.47713 6.71144,-3.87496 l 24.78194,-42.922974 c 1.38414,-2.397828 1.38414,-5.3521 0,-7.749927 L 121.88049,42.814746 c -1.38414,-2.397828 -3.94239,-3.874964 -6.71144,-3.874964 H 65.605944 c -2.768739,0 -5.327223,1.477059 -6.711592,3.874964 z" style="stroke-width:0.774993" /></svg></span>
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+        <script defer src="/en.search.js" integrity=""></script>
+  </body>
+</html>
diff --git a/public/courses/spring-boot/index.xml b/public/courses/spring-boot/index.xml
new file mode 100644
index 0000000..14b878c
--- /dev/null
+++ b/public/courses/spring-boot/index.xml
@@ -0,0 +1,18 @@
+<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom">
+  <channel>
+    <title>CodeJava – </title>
+    <link>http://localhost:1313/courses/spring-boot/</link>
+    <description>Recent content on CodeJava</description>
+    <generator>Hugo -- gohugo.io</generator>
+    <language>en</language>
+    
+	  <atom:link href="http://localhost:1313/courses/spring-boot/index.xml" rel="self" type="application/rss+xml" />
+    
+    
+      
+        
+      
+    
+    
+  </channel>
+</rss>
diff --git a/public/en.search-data.json b/public/en.search-data.json
index 9e26dfe..6c1dd08 100644
--- a/public/en.search-data.json
+++ b/public/en.search-data.json
@@ -1 +1 @@
-{}
\ No newline at end of file
+{"/courses/prog-intro/lectures/intro/":{"data":{"what-does-java-consist-of#What does Java consist of?":"Java consists of multiple main components. The first one being the Java compiler. The process of converting human-readable text to machine code is called compilation.\nImg.2 - Simplified Compilation Process","why-do-we-choose-java#Why do we choose Java?":"Why do we choose Java?According to TIOBE Programming Community Index Java is one of the most demanded languages in the programming field.\nImg. 1 - TIOBE Programming Community Index\nAlso, Java has a lot of advantages for beginners such as:\nIt’s fairly easy It has a broad spectre of usage Server Desktop Mobile devices Smart-cards"},"title":"Lecture 1. Introduction"},"/courses/spring-boot/":{"data":{"prerequisites#Prerequisites":"Prerequisites Solid understanding of Java Object-oriented programming Classes, methods and interfaces Basic understanding of databases Tables, primary keys, foreign keys, relationships, etc. Write basic SQL statements","what-is-a-spring-framework#What is a Spring Framework?":"Spring – is a popular framework for building Java applications. It has a lot of modules, each designed to handle a specific task. They are combined into few different layers.\nImg. 1 – Spring layers\nAt the core we have modules"},"title":"_index"}}
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diff --git a/public/index.html b/public/index.html
index a07b0f8..748ab97 100644
--- a/public/index.html
+++ b/public/index.html
@@ -158,6 +158,14 @@
         <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
     href="/courses/prog-intro/"
     
   >Introduction to Programming in Java
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+++ b/public/sitemap.xml
@@ -5,6 +5,8 @@
     <loc>http://localhost:1313/</loc>
   </url><url>
     <loc>http://localhost:1313/courses/</loc>
+  </url><url>
+    <loc>http://localhost:1313/courses/spring-boot/</loc>
   </url><url>
     <loc>http://localhost:1313/courses/prog-intro/</loc>
   </url><url>
diff --git a/public/tags/index.html b/public/tags/index.html
index 67e1453..55fdb9f 100644
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         <ul class='hx:relative hx:flex hx:flex-col hx:gap-1 hx:before:absolute hx:before:inset-y-1 hx:before:w-px hx:before:bg-gray-200 hx:before:content-[""] hx:ltr:ml-3 hx:ltr:pl-3 hx:ltr:before:left-0 hx:rtl:mr-3 hx:rtl:pr-3 hx:rtl:before:right-0 hx:dark:before:bg-neutral-800'><li class="hx:flex hx:flex-col "><a
     class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
       hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
+    href="/courses/spring-boot/"
+    
+  >Spring Boot
+    </a>
+              
+            </li><li class="hx:flex hx:flex-col "><a
+    class="hx:flex hx:items-center hx:justify-between hx:gap-2 hx:cursor-pointer hx:rounded-sm hx:px-2 hx:py-1.5 hx:text-sm hx:transition-colors [-webkit-tap-highlight-color:transparent] [-webkit-touch-callout:none] [word-break:break-word]
+      hx:text-gray-500 hx:hover:bg-gray-100 hx:hover:text-gray-900 hx:contrast-more:border hx:contrast-more:border-transparent hx:contrast-more:text-gray-900 hx:contrast-more:hover:border-gray-900 hx:dark:text-neutral-400 hx:dark:hover:bg-primary-100/5 hx:dark:hover:text-gray-50 hx:contrast-more:dark:text-gray-50 hx:contrast-more:dark:hover:border-gray-50"
     href="/courses/prog-intro/"
     
   >Introduction to Programming in Java