diff --git a/Cargo.toml b/Cargo.toml
index 63ed006..2b94780 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -61,6 +61,8 @@ base64 = { version = "0.22", default-features = false, features = ["std"] }
 serde = { version = "1.0", default-features = false, features = ["derive"] }
 serde_urlencoded = { version = "0.7", default-features = false }
 lazy_static = { version = "1.5", default-features = false }
+http = "1.2.0"
+mime = "0.3.17"
 
 [build-dependencies]
 embuild = "0.33"
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diff --git a/src/ota/mod.rs b/src/ota/mod.rs
index 70b786d..3abd427 100644
--- a/src/ota/mod.rs
+++ b/src/ota/mod.rs
@@ -1 +1,105 @@
 // TODO
+use core::mem::size_of;
+
+use embedded_svc::http::Headers;
+use http::header::ACCEPT;
+use http::Uri;
+use embedded_svc::ota::FirmwareInfo;
+use embedded_svc::http::{client::Client, Method};
+use esp_idf_svc::http::client::{Configuration, EspHttpConnection};
+use esp_idf_svc::ota::EspOta;
+use esp_idf_svc::sys::{EspError, ESP_ERR_IMAGE_INVALID, ESP_ERR_INVALID_RESPONSE};
+
+/// Macro to quickly create EspError from an ESP_ERR_ constant.
+#[macro_export]
+macro_rules! esp_err {
+    ($x:ident) => {
+        EspError::from_infallible::<$x>()
+    };
+}
+
+// Config to use once https is enabled
+// 
+//use esp_idf_svc::sys::esp_crt_bundle_attach;
+//
+//...
+//Configuration {
+//	buffer_size: Some(1024 * 4),
+//	use_global_ca_store: true,
+//	crt_bundle_attach: Some(esp_crt_bundle_attach),
+//	..Default::default()
+//}
+
+
+const FIRMWARE_DOWNLOAD_CHUNK_SIZE: usize = 1024 * 20;
+// Not expect firmware bigger than 2MB
+const FIRMWARE_MAX_SIZE: usize = 1024 * 1024 * 2;
+const FIRMWARE_MIN_SIZE: usize = size_of::<FirmwareInfo>() + 1024;
+
+pub fn download_and_update_firmware(url: Uri) -> Result<(), EspError> {
+    let mut client = Client::wrap(EspHttpConnection::new(&Configuration {
+        buffer_size: Some(1024 * 4),
+        ..Default::default()
+    })?);
+    let headers = [(ACCEPT.as_str(), mime::APPLICATION_OCTET_STREAM.as_ref())];
+    let surl = url.to_string();
+    let request = client
+        .request(Method::Get, &surl, &headers)
+        .map_err(|e| e.0)?;
+    let mut response = request.submit().map_err(|e| e.0)?;
+    if response.status() != 200 {
+        log::info!("Bad HTTP response: {}", response.status());
+        return Err(esp_err!(ESP_ERR_INVALID_RESPONSE));
+    }
+    let file_size = response.content_len().unwrap_or(0) as usize;
+    if file_size <= FIRMWARE_MIN_SIZE {
+        log::info!(
+            "File size is {file_size}, too small to be a firmware! No need to proceed further."
+        );
+        return Err(esp_err!(ESP_ERR_IMAGE_INVALID));
+    }
+    if file_size > FIRMWARE_MAX_SIZE {
+        log::info!("File is too big ({file_size} bytes).");
+        return Err(esp_err!(ESP_ERR_IMAGE_INVALID));
+    }
+    let mut ota = EspOta::new()?;
+    let mut work = ota.initiate_update()?;
+    let mut buff = vec![0; FIRMWARE_DOWNLOAD_CHUNK_SIZE];
+    let mut total_read_len: usize = 0;
+    let mut got_info = false;
+    let dl_result = loop {
+        let n = response.read(&mut buff).unwrap_or_default();
+        total_read_len += n;
+        if !got_info {
+            match get_firmware_info(&buff[..n]) {
+                Ok(info) => log::info!("Firmware to be downloaded: {info:?}"),
+                Err(e) => {
+                    log::error!("Failed to get firmware info from downloaded bytes!");
+                    break Err(e);
+                }
+            };
+            got_info = true;
+        }
+        if n > 0 {
+            if let Err(e) = work.write(&buff[..n]) {
+                log::error!("Failed to write to OTA. {e}");
+                break Err(e);
+            }
+        }
+        if total_read_len >= file_size {
+            break Ok(());
+        }
+    };
+    if dl_result.is_err() {
+        return work.abort();
+    }
+    if total_read_len < file_size {
+        log::error!("Supposed to download {file_size} bytes, but we could only get {total_read_len}. May be network error?");
+        return work.abort();
+    }
+    work.complete()
+}
+
+fn get_firmware_info(buff: &[u8]) -> Result<(), EspError>{
+    todo!()
+}
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