diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1117cfa..2c70b1d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -29,8 +29,8 @@ list(APPEND FLAGS -Werror -Wall -Wextra -Wshadow -Wpedantic -Wno-gnu-anonymous-s
 add_link_options(${FLAGS})
 
 
-add_executable(${PROJECT_NAME} main.cpp numberhelper.cpp config.cpp models.cpp client.cpp servehelper.cpp timeutils.cpp hiredis_wrapper.cpp
-    routes/home.cpp routes/css.cpp routes/user.cpp routes/status.cpp routes/tags.cpp routes/about.cpp
+add_executable(${PROJECT_NAME} main.cpp numberhelper.cpp config.cpp settings.cpp models.cpp client.cpp servehelper.cpp timeutils.cpp hiredis_wrapper.cpp
+    routes/home.cpp routes/css.cpp routes/user.cpp routes/status.cpp routes/tags.cpp routes/about.cpp routes/user_settings.cpp
     blankie/serializer.cpp blankie/escape.cpp)
 set_target_properties(${PROJECT_NAME}
     PROPERTIES
diff --git a/main.cpp b/main.cpp
index fc60f0e..ece043f 100644
--- a/main.cpp
+++ b/main.cpp
@@ -40,9 +40,13 @@ int main(int argc, char** argv) {
     atexit(MastodonClient::cleanup);
 
     httplib::Server server;
+    server.set_payload_max_length(8192);
 
     server.Get("/", home_route);
     server.Get("/style.css", css_route);
+    server.Get("/settings", user_settings_route);
+    server.Post("/settings", user_settings_route);
+
     server.Get("/(" DOMAIN_RE ")/@(" ACCT_RE ")(|/with_replies|/media)", user_route);
     server.Get("/(" DOMAIN_RE ")/users/(" ACCT_RE ")(|/with_replies|/media)", [](const httplib::Request& req, httplib::Response& res) {
         serve_redirect(req, res, get_origin(req) + '/' + req.matches.str(1) + "/@" + req.matches.str(2) + req.matches.str(3), true);
diff --git a/routes/css.cpp b/routes/css.cpp
index d6939e9..0fb7013 100644
--- a/routes/css.cpp
+++ b/routes/css.cpp
@@ -14,6 +14,10 @@ static const constexpr char css[] = R"EOF(
     --error-border-color: red;
     --error-text-color: white;
 
+    --success-background-color: green;
+    --success-border-color: lightgreen;
+    --success-text-color: white;
+
     --accent-color: #962AC3;
     --bright-accent-color: #DE6DE6;
 }
@@ -163,6 +167,20 @@ svg {
     padding: revert;
 }
 
+/* SUCCESS BOX */
+.success {
+    text-align: center;
+    background-color: var(--success-background-color);
+    color: var(--success-text-color);
+    border-style: solid;
+    border-color: var(--success-border-color);
+    margin-bottom: 0.5em;
+}
+.success * {
+    margin: revert;
+    padding: revert;
+}
+
 /* USER PAGE */
 .user_page-header {
     width: 100%;
@@ -252,6 +270,18 @@ svg {
     margin: revert;
     padding: revert;
 }
+
+/* USER SETTINGS PAGE */
+.user_settings_page-form {
+    display: inline;
+}
+.user_settings_page-form input[type=submit] {
+    margin-top: 0.5em;
+    padding: revert;
+}
+.user_settings_page-form .cancel {
+    margin-left: 0.25em;
+}
 )EOF";
 // one for \0, one for trailing newline
 #define CSS_LEN sizeof(css) / sizeof(css[0]) - 2
diff --git a/routes/home.cpp b/routes/home.cpp
index 0a1f053..5443c26 100644
--- a/routes/home.cpp
+++ b/routes/home.cpp
@@ -8,6 +8,7 @@ void home_route(const httplib::Request& req, httplib::Response& res) {
             "their posts, posts themselves (and their context), posts with a certain hashtag, "
             "and instance details.",
         }),
+        Element("p", {Element("a", {{"href", get_origin(req) + "/settings"}}, {"Configure settings"})}),
         Element("h2", {"Example links"}),
         Element("ul", {
             Element("li", {Element("a", {{"href", get_origin(req) + "/vt.social/@lina"}}, {"Asahi Lina (朝日リナ) // nullptr::live"})}),
diff --git a/routes/routes.h b/routes/routes.h
index a38898f..b91e042 100644
--- a/routes/routes.h
+++ b/routes/routes.h
@@ -10,3 +10,4 @@ void user_route(const httplib::Request& req, httplib::Response& res);
 void status_route(const httplib::Request& req, httplib::Response& res);
 void tags_route(const httplib::Request& req, httplib::Response& res);
 void about_route(const httplib::Request& req, httplib::Response& res);
+void user_settings_route(const httplib::Request& req, httplib::Response& res);
diff --git a/routes/user_settings.cpp b/routes/user_settings.cpp
new file mode 100644
index 0000000..f57866b
--- /dev/null
+++ b/routes/user_settings.cpp
@@ -0,0 +1,64 @@
+#include "routes.h"
+#include "../servehelper.h"
+#include "../settings.h"
+#include "../timeutils.h"
+#include "../curlu_wrapper.h"
+
+static void set_cookie(const httplib::Request& req, httplib::Response& res, const char* key, std::string_view value);
+
+
+void user_settings_route(const httplib::Request& req, httplib::Response& res) {
+    UserSettings settings;
+
+    if (req.method == "POST") {
+        for (const auto& i : req.params) {
+            settings.set(i.first, i.second);
+        }
+
+        set_cookie(req, res, "auto-open-cw", settings.auto_open_cw ? "true" : "false");
+    } else {
+        settings.load_from_cookies(req);
+    }
+
+    Element auto_open_cw_checkbox("input", {{"type", "checkbox"}, {"name", "auto-open-cw"}, {"value", "true"}}, {});
+    if (settings.auto_open_cw) {
+        auto_open_cw_checkbox.attributes.push_back({"checked", ""});
+    }
+
+    Element body("body", {
+        Element("form", {{"class", "user_settings_page-form"}, {"method", "post"}}, {
+            Element("label", {
+                std::move(auto_open_cw_checkbox),
+                " Automatically open Content Warnings",
+            }),
+
+            Element("br"),
+            Element("input", {{"type", "submit"}, {"value", "Save"}}, {}),
+        }),
+        Element("form", {{"class", "user_settings_page-form"}, {"method", "get"}, {"action", get_origin(req)}}, {
+            Element("input", {{"class", "cancel"}, {"type", "submit"}, {"value", "Cancel"}}, {}),
+        }),
+    });
+    if (req.method == "POST") {
+        body.nodes.insert(body.nodes.begin(), Element("div", {{"class", "success"}}, {
+            Element("h3", {"Settings saved!"}),
+        }));
+    }
+
+    serve(req, res, "User settings", std::move(body));
+}
+
+
+static void set_cookie(const httplib::Request& req, httplib::Response& res, const char* key, std::string_view value) {
+    CurlUrl origin;
+    origin.set(CURLUPART_URL, get_origin(req));
+
+    std::string header = std::string(key) + '=' + std::string(value)
+        + "; HttpOnly; SameSite=Strict; Domain=" + origin.get(CURLUPART_HOST).get() + "; Path=" + origin.get(CURLUPART_PATH).get()
+        + "; Expires=" + to_web_date(current_time() + 365 * 24 * 60 * 60);
+    if (strcmp(origin.get(CURLUPART_SCHEME).get(), "https") == 0) {
+        header += "; Secure";
+    }
+
+    res.set_header("Set-Cookie", header);
+}
diff --git a/servehelper.cpp b/servehelper.cpp
index 8a526d3..1a613b8 100644
--- a/servehelper.cpp
+++ b/servehelper.cpp
@@ -6,6 +6,7 @@
 
 #include "font_awesome.h"
 #include "config.h"
+#include "settings.h"
 #include "models.h"
 #include "timeutils.h"
 #include "servehelper.h"
@@ -394,6 +395,9 @@ static Element serialize_post(const httplib::Request& req, const std::string& se
             Element("summary", {preprocess_html(req, post.emojis, std::move(spoiler_text))}),
             std::move(contents),
         });
+        if (UserSettings(req).auto_open_cw) {
+            contents.attributes.push_back({"open", ""});
+        }
     }
 
     Element div("div", {{"class", "post"}}, {
diff --git a/settings.cpp b/settings.cpp
new file mode 100644
index 0000000..9890c2d
--- /dev/null
+++ b/settings.cpp
@@ -0,0 +1,75 @@
+#include <string>
+#include <stdexcept>
+#include "settings.h"
+
+static void set_settings(std::string_view str, const char* delimiter, UserSettings& settings);
+static inline bool lowercase_compare(std::string_view lhs, std::string_view rhs);
+static bool parse_bool(std::string_view value);
+
+
+void UserSettings::set(std::string_view key, std::string_view value) {
+    if (key == "auto-open-cw") {
+        this->auto_open_cw = parse_bool(value);
+    }
+}
+
+void UserSettings::load_from_cookies(const httplib::Request& req) {
+    for (const auto& i : req.headers) {
+        if (lowercase_compare(i.first, "cookie")) {
+            set_settings(i.second, "; ", *this);
+        }
+    }
+}
+
+
+static void set_settings(std::string_view str, const char* delimiter, UserSettings& settings) {
+    using namespace std::string_literals;
+    size_t offset = 0;
+    size_t new_offset = 0;
+    size_t delimiter_len = strlen(delimiter);
+
+    while (offset < str.size()) {
+        new_offset = str.find(delimiter, offset);
+
+        std::string_view item = str.substr(offset, new_offset != std::string_view::npos ? new_offset - offset : std::string_view::npos);
+        size_t equal_offset = item.find('=');
+        if (equal_offset == std::string_view::npos) {
+            throw std::invalid_argument("invalid user setting item: "s + std::string(item));
+        }
+        settings.set(item.substr(0, equal_offset), item.substr(equal_offset + 1));
+
+        if (new_offset == std::string_view::npos) {
+            break;
+        }
+        offset = new_offset + delimiter_len;
+    }
+}
+
+static inline bool lowercase_compare(std::string_view lhs, std::string_view rhs) {
+    if (lhs.size() != rhs.size()) {
+        return false;
+    }
+
+    auto lower = [](char c) {
+        return c >= 'A' && c <= 'Z' ? c - 'A' + 'a' : c;
+    };
+    for (size_t i = 0; i < lhs.size(); i++) {
+        if (lower(lhs[i]) != lower(rhs[i])) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+static bool parse_bool(std::string_view value) {
+    using namespace std::string_literals;
+
+    if (value == "true") {
+        return true;
+    } else if (value == "false") {
+        return false;
+    } else {
+        throw std::invalid_argument("unknown boolean value: "s + std::string(value));
+    }
+}
diff --git a/settings.h b/settings.h
new file mode 100644
index 0000000..c20cf59
--- /dev/null
+++ b/settings.h
@@ -0,0 +1,16 @@
+#pragma once
+
+#include <string_view>
+#include <httplib/httplib.h>
+
+struct UserSettings {
+    bool auto_open_cw = false;
+
+    UserSettings() = default;
+    UserSettings(const httplib::Request& req) {
+        this->load_from_cookies(req);
+    }
+
+    void set(std::string_view key, std::string_view value);
+    void load_from_cookies(const httplib::Request& req);
+};
diff --git a/timeutils.cpp b/timeutils.cpp
index c6daf0b..d0fc608 100644
--- a/timeutils.cpp
+++ b/timeutils.cpp
@@ -1,3 +1,4 @@
+#include <cstring>
 #include <system_error>
 
 #include "timeutils.h"
@@ -39,6 +40,19 @@ std::string to_rfc3339(time_t time) {
     return std::string(buf, len);
 }
 
+static const char* day_names[] = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};
+static const char* month_names[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
+std::string to_web_date(time_t time) {
+    struct tm tm;
+    gmtime_r(&time, &tm);
+
+    char buf[32];
+    size_t len = strftime(buf, 32, "XXX, %d XXX %Y %H:%M:%S GMT", &tm);
+    memcpy(buf, day_names[tm.tm_wday], 3);
+    memcpy(buf + 3 + 2 + 2 + 1, month_names[tm.tm_mon], 3);
+    return std::string(buf, len);
+}
+
 std::string relative_time(time_t from, time_t to) {
     time_t diff = to - from;
 
diff --git a/timeutils.h b/timeutils.h
index 35ae574..7fd3343 100644
--- a/timeutils.h
+++ b/timeutils.h
@@ -8,4 +8,5 @@ time_t current_time();
 std::string short_time(time_t time);
 std::string full_time(time_t time);
 std::string to_rfc3339(time_t time);
+std::string to_web_date(time_t time);
 std::string relative_time(time_t from, time_t to);