diff --git a/.github/workflows/docs.yaml b/.github/workflows/docs.yaml
new file mode 100644
index 0000000000..8510de7a0e
--- /dev/null
+++ b/.github/workflows/docs.yaml
@@ -0,0 +1,21 @@
+name: Doxygen
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  deploy:
+    name: Build and deploy documentation
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Build
+        uses: mattnotmitt/doxygen-action@v1
+
+      - name: Deploy
+        uses: peaceiris/actions-gh-pages@v3
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: ./docs/doxygen
diff --git a/.gitignore b/.gitignore
index bd79c043b6..3bec7105a3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,3 +17,4 @@ assets
 *.bin
 bin/
 build/
+docs/doxygen/
diff --git a/Doxyfile b/Doxyfile
new file mode 100644
index 0000000000..18f877500c
--- /dev/null
+++ b/Doxyfile
@@ -0,0 +1,112 @@
+# https://www.doxygen.nl/manual/config.html
+
+PROJECT_NAME           = "Paper Mario"
+PROJECT_NUMBER         =
+PROJECT_BRIEF          = "Decompilation of Paper Mario"
+PROJECT_LOGO           =
+
+OUTPUT_DIRECTORY       = docs
+CREATE_SUBDIRS         = NO
+ALLOW_UNICODE_NAMES    = YES
+
+OPTIMIZE_OUTPUT_FOR_C  = YES
+
+TYPEDEF_HIDES_STRUCT   = YES
+
+NUM_PROC_THREADS       = 0
+
+EXTRACT_ALL            = YES
+EXTRACT_STATIC         = YES
+HIDE_UNDOC_CLASSES     = NO
+HIDE_IN_BODY_DOCS      = YES
+SHOW_GROUPED_MEMB_INC  = YES
+
+FORCE_LOCAL_INCLUDES   = YES
+INLINE_INFO            = YES
+
+SORT_MEMBER_DOCS       = NO
+SORT_BRIEF_DOCS        = NO
+SORT_GROUP_NAMES       = NO
+
+GENERATE_TODOLIST      = NO
+GENERATE_TESTLIST      = NO
+GENERATE_BUGLIST       = YES
+GENERATE_DEPRECATEDLIST= NO
+
+DISABLE_INDEX          = YES
+GENERATE_TREEVIEW      = YES
+
+ENABLED_SECTIONS       =
+MAX_INITIALIZER_LINES  = 1
+
+SHOW_INCLUDE_FILES     = NO
+SHOW_USED_FILES        = YES
+SHOW_FILES             = YES
+SHOW_NAMESPACES        = NO
+
+QUIET                  = NO
+WARNINGS               = YES
+WARN_IF_UNDOCUMENTED   = NO
+WARN_IF_DOC_ERROR      = YES
+WARN_NO_PARAMDOC       = NO
+WARN_AS_ERROR          = YES
+WARN_FORMAT            = "$file:$line: $text"
+WARN_LOGFILE           =
+
+INPUT                  = README.md src include
+FILE_PATTERNS          = *.c *.h
+RECURSIVE              = YES
+EXCLUDE                = include/nu include/PR include/ultra64.h
+EXCLUDE_SYMLINKS       = NO
+EXCLUDE_PATTERNS       =
+EXCLUDE_SYMBOLS        =
+
+USE_MDFILE_AS_MAINPAGE = README.md
+
+SOURCE_BROWSER         = YES
+INLINE_SOURCES         = NO
+STRIP_CODE_COMMENTS    = YES
+REFERENCED_BY_RELATION = YES
+REFERENCES_RELATION    = NO
+REFERENCES_LINK_SOURCE = NO
+SOURCE_TOOLTIPS        = YES
+USE_HTAGS              = NO
+VERBATIM_HEADERS       = NO
+
+ALPHABETICAL_INDEX     = NO
+COLS_IN_ALPHA_INDEX    = 5
+IGNORE_PREFIX          =
+
+GENERATE_HTML          = YES
+HTML_OUTPUT            = doxygen
+HTML_HEADER            = docs/doxygen_header.html
+HTML_FOOTER            =
+HTML_EXTRA_STYLESHEET  = docs/doxygen_custom.css
+HTML_EXTRA_FILES       =
+HTML_COLORSTYLE_HUE    = 220
+HTML_COLORSTYLE_SAT    = 100
+HTML_COLORSTYLE_GAMMA  = 80
+HTML_TIMESTAMP         = YES
+HTML_DYNAMIC_MENUS     = YES
+HTML_DYNAMIC_SECTIONS  = YES
+HTML_INDEX_NUM_ENTRIES = 100
+HTML_FORMULA_FORMAT    = svg
+
+USE_MATHJAX            = YES
+MATHJAX_FORMAT         = SVG
+
+SEARCHENGINE           = YES
+SERVER_BASED_SEARCH    = NO
+
+GENERATE_LATEX         = NO
+
+ENABLE_PREPROCESSING   = YES
+MACRO_EXPANSION        = YES
+EXPAND_ONLY_PREDEF     = YES
+PREDEFINED             = DOXYGEN NON_MATCHING __attribute__((x))=
+EXPAND_AS_DEFINED      = INCLUDE_ASM
+SKIP_FUNCTION_MACROS   = YES
+
+SEARCH_INCLUDES        = YES
+INCLUDE_PATH           = include include/PR src
+INCLUDE_FILE_PATTERNS  =
diff --git a/docs/doxygen_custom.css b/docs/doxygen_custom.css
new file mode 100644
index 0000000000..877606101a
--- /dev/null
+++ b/docs/doxygen_custom.css
@@ -0,0 +1,150 @@
+/* typography */
+
+body, table, div, p, dl { font: inherit }
+
+body, table, div, p, dl, p.reference, p.definition, .memberdecls .header {
+    color: #121212;
+    font-family: -apple-system, BlinkMacSystemFont, Segoe UI, Helvetica, Arial, sans-serif, Apple Color Emoji, Segoe UI Emoji;
+}
+
+:root { font-size: 10px } /* rem multiplier */
+h1 { font-size: 3rem; }
+h2 { font-size: 2.25rem; }
+h3 { font-size: 1.5rem; }
+h4 { font-size: 1.25rem; }
+h5 { font-size: 1rem; }
+h6 { font-size: .875rem; }
+h1, h2, h3, h4, h5, h6 { margin-bottom: 3px }
+h1 { border-bottom: 1px solid #eee }
+
+.contents a:any-link { color: #357edd }
+.contents a.visited { color: #5e2ca5 }
+
+p.reference,         p.definition { color: #959da5; font-weight: normal; font-size: 11px; line-height: 1.2 }
+p.reference a,       p.definition a { color: #959da5 !important }
+p.reference a:hover, p.definition a:hover { color: #357edd }
+
+.memname, .fragment, .memberdecls, .fragment .line, code {
+    font-family: SFMono-Regular, Consolas, Liberation Mono, Menlo, monospace;
+}
+
+#PageDoc, .content, p {
+    font-size: 16px;
+    line-height: 1.5;
+    color: #1b1f23;
+}
+
+hr {
+    border-color: #eee;
+    margin: 2em;
+}
+
+/* layout */
+
+html { height: 100% }
+
+body {
+    display: flex;
+    flex-direction: row;
+
+    width: 100%;
+    max-width: 1000px;
+    min-height: 100%;
+    margin: 0 auto;
+}
+
+#side-nav {
+    position: relative;
+    width: 250px !important;
+}
+
+.ui-resizable-handle, #nav-sync { display: none !important }
+
+#doc-content {
+    margin-left: 0 !important;
+    flex: 1;
+}
+
+#nav-path { display: none } /* hide footer */
+#MathJax_Message { display: none } /* hide "MathJax loading..." message */
+
+#MSearchBox {
+    position: fixed;
+    top: 1em;
+    right: 1em;
+}
+
+.contents {
+    font-size: 16px;
+    padding-top: 1em;
+    padding-bottom: 2em;
+}
+
+/*
+table {
+    table-layout: fixed;
+    width: 100%;
+}
+.memItemLeft { width: 32ch }
+*/
+
+/* cleaning */
+
+#details + .groupheader,
+.definition,
+.memtitle,
+.contents > p:first-child > a:first-child /* "Go to the source code of this file." */
+{ display: none }
+
+table.memname * {
+    display: inline;
+}
+
+/* candy */
+
+div.fragment, .memproto {
+    padding: 16px;
+    border: 0;
+    border-radius: 6px;
+    background: #f6f8fa;
+}
+
+div.fragment div.line {
+    font-size: 85%;
+    line-height: 1.45;
+}
+
+code {
+    padding: .2em .4em;
+    margin: 0;
+    font-size: 85%;
+    background: #f6f8fa;
+}
+
+.memitem {
+    display: block !important;
+    border-left: 1px solid #eee;
+    padding-left: 1em;
+    margin: 1em 0;
+    width: 100%;
+    box-sizing: border-box;
+}
+
+.memproto {
+    padding: 8px;
+    margin-bottom: .5em;
+    box-shadow: none;
+    text-shadow: none;
+    display: inline-block;
+}
+
+.memname {
+    margin-left: 0;
+}
+
+.memdoc {
+    border: 0;
+    padding: 0;
+    box-shadow: none;
+    background: none;
+}
diff --git a/docs/doxygen_header.html b/docs/doxygen_header.html
new file mode 100644
index 0000000000..5ace5202f1
--- /dev/null
+++ b/docs/doxygen_header.html
@@ -0,0 +1,22 @@
+<!doctype html>
+<html lang='en'> <!-- closed by doxygen-->
+    <head>
+        <meta charset='utf-8'>
+        <meta name='generator' content='Doxygen $doxygenversion'>
+        <meta name='viewport' content='width=device-width, initial-scale=1'>
+
+        <!--BEGIN PROJECT_NAME--><title>$title - $projectname Documentation</title><!--END PROJECT_NAME-->
+        <!--BEGIN !PROJECT_NAME--><title>$title</title><!--END !PROJECT_NAME-->
+        <link href="$relpath^tabs.css" rel="stylesheet" type="text/css"/>
+        <script type="text/javascript" src="$relpath^jquery.js"></script>
+        <script type="text/javascript" src="$relpath^dynsections.js"></script>
+        $treeview
+        $search
+        $mathjax
+        <link href="$relpath^$stylesheet" rel="stylesheet" type="text/css" />
+        $extrastylesheet
+    </head>
+
+    <body> <!-- closed by doxygen-->
+        <div> <!-- closed by doxygen-->
+            $searchbox
diff --git a/install.sh b/install.sh
index cc7f568767..efbc4324cc 100755
--- a/install.sh
+++ b/install.sh
@@ -9,7 +9,7 @@ if command -v apt &> /dev/null; then
 
     if [[ $1 == "--extra" ]]; then
         echo "Installing extra"
-        sudo apt install -y clang-tidy astyle || exit 1
+        sudo apt install -y clang-tidy astyle doxygen || exit 1
         python3 -m pip install -U -r requirements_extra.txt || exit 1
     fi
 
@@ -50,7 +50,7 @@ if command -v pacman &> /dev/null; then
 
     if [[ $1 == "--extra" ]]; then
         echo "Installing extra"
-        sudo pacman -S --noconfirm --needed clang astyle || exit 1
+        sudo pacman -S --noconfirm --needed clang astyle doxygen || exit 1
         python3 -m pip install -U -r requirements_extra.txt || exit 1
     fi
 
@@ -85,7 +85,7 @@ if command -v zypper &> /dev/null; then
 
     if [[ $1 == "--extra" ]]; then
         echo "Installing extra"
-        sudo zypper -n install clang astyle || exit 1
+        sudo zypper -n install clang astyle doxygen || exit 1
         python3 -m pip install -U -r requirements_extra.txt || exit 1
     fi
 
@@ -141,7 +141,7 @@ if command -v apk &> /dev/null; then
 
     if [[ $1 == "--extra" ]]; then
         echo "Installing extra"
-        sudo apk add --no-cache clang-extra-tools astyle || exit 1
+        sudo apk add --no-cache clang-extra-tools astyle doxygen || exit 1
         python3 -m pip install -U -r requirements_extra.txt || exit 1
     fi