diff --git a/ci.sh b/ci.sh
index 760d6fbf..3fe1b1ce 100755
--- a/ci.sh
+++ b/ci.sh
@@ -133,16 +133,16 @@ cargo batch  \
     --- build --release --manifest-path examples/stm32u5/Cargo.toml --target thumbv8m.main-none-eabihf --out-dir out/examples/stm32u5 \
     --- build --release --manifest-path examples/stm32wb/Cargo.toml --target thumbv7em-none-eabihf --out-dir out/examples/stm32wb \
     --- build --release --manifest-path examples/stm32wl/Cargo.toml --target thumbv7em-none-eabihf --out-dir out/examples/stm32wl \
-    --- build --release --manifest-path examples/boot/application/nrf/Cargo.toml --target thumbv7em-none-eabi --features embassy-nrf/nrf52840 --out-dir out/examples/boot/nrf --bin b \
-    --- build --release --manifest-path examples/boot/application/nrf/Cargo.toml --target thumbv8m.main-none-eabihf --features embassy-nrf/nrf9160-ns --out-dir out/examples/boot/nrf --bin b \
-    --- build --release --manifest-path examples/boot/application/rp/Cargo.toml --target thumbv6m-none-eabi --out-dir out/examples/boot/rp --bin b \
-    --- build --release --manifest-path examples/boot/application/stm32f3/Cargo.toml --target thumbv7em-none-eabi --out-dir out/examples/boot/stm32f3 --bin b \
-    --- build --release --manifest-path examples/boot/application/stm32f7/Cargo.toml --target thumbv7em-none-eabi --out-dir out/examples/boot/stm32f7 --bin b \
-    --- build --release --manifest-path examples/boot/application/stm32h7/Cargo.toml --target thumbv7em-none-eabi --out-dir out/examples/boot/stm32h7 --bin b \
-    --- build --release --manifest-path examples/boot/application/stm32l0/Cargo.toml --target thumbv6m-none-eabi --out-dir out/examples/boot/stm32l0 --bin b \
-    --- build --release --manifest-path examples/boot/application/stm32l1/Cargo.toml --target thumbv7m-none-eabi --out-dir out/examples/boot/stm32l1 --bin b \
-    --- build --release --manifest-path examples/boot/application/stm32l4/Cargo.toml --target thumbv7em-none-eabi --out-dir out/examples/boot/stm32l4 --bin b \
-    --- build --release --manifest-path examples/boot/application/stm32wl/Cargo.toml --target thumbv7em-none-eabihf --out-dir out/examples/boot/stm32wl --bin b \
+    --- build --release --manifest-path examples/boot/application/nrf/Cargo.toml --target thumbv7em-none-eabi --features embassy-nrf/nrf52840,skip-include --out-dir out/examples/boot/nrf  \
+    --- build --release --manifest-path examples/boot/application/nrf/Cargo.toml --target thumbv8m.main-none-eabihf --features embassy-nrf/nrf9160-ns,skip-include --out-dir out/examples/boot/nrf \
+    --- build --release --manifest-path examples/boot/application/rp/Cargo.toml --target thumbv6m-none-eabi --features skip-include --out-dir out/examples/boot/rp \
+    --- build --release --manifest-path examples/boot/application/stm32f3/Cargo.toml --target thumbv7em-none-eabi --features skip-include --out-dir out/examples/boot/stm32f3 \
+    --- build --release --manifest-path examples/boot/application/stm32f7/Cargo.toml --target thumbv7em-none-eabi --features skip-include --out-dir out/examples/boot/stm32f7 \
+    --- build --release --manifest-path examples/boot/application/stm32h7/Cargo.toml --target thumbv7em-none-eabi --features skip-include --out-dir out/examples/boot/stm32h7 \
+    --- build --release --manifest-path examples/boot/application/stm32l0/Cargo.toml --target thumbv6m-none-eabi --features skip-include --out-dir out/examples/boot/stm32l0 \
+    --- build --release --manifest-path examples/boot/application/stm32l1/Cargo.toml --target thumbv7m-none-eabi --features skip-include --out-dir out/examples/boot/stm32l1 \
+    --- build --release --manifest-path examples/boot/application/stm32l4/Cargo.toml --target thumbv7em-none-eabi --features skip-include --out-dir out/examples/boot/stm32l4 \
+    --- build --release --manifest-path examples/boot/application/stm32wl/Cargo.toml --target thumbv7em-none-eabihf --features skip-include --out-dir out/examples/boot/stm32wl \
     --- build --release --manifest-path examples/boot/bootloader/nrf/Cargo.toml --target thumbv7em-none-eabi --features embassy-nrf/nrf52840 \
     --- build --release --manifest-path examples/boot/bootloader/nrf/Cargo.toml --target thumbv8m.main-none-eabihf --features embassy-nrf/nrf9160-ns \
     --- build --release --manifest-path examples/boot/bootloader/rp/Cargo.toml --target thumbv6m-none-eabi \
diff --git a/examples/boot/application/nrf/Cargo.toml b/examples/boot/application/nrf/Cargo.toml
index 5939a43b..b98f73f3 100644
--- a/examples/boot/application/nrf/Cargo.toml
+++ b/examples/boot/application/nrf/Cargo.toml
@@ -24,3 +24,4 @@ cortex-m-rt = "0.7.0"
 [features]
 ed25519-dalek = ["embassy-boot/ed25519-dalek"]
 ed25519-salty = ["embassy-boot/ed25519-salty"]
+skip-include = []
diff --git a/examples/boot/application/nrf/src/bin/a.rs b/examples/boot/application/nrf/src/bin/a.rs
index 06c23778..021d77f3 100644
--- a/examples/boot/application/nrf/src/bin/a.rs
+++ b/examples/boot/application/nrf/src/bin/a.rs
@@ -12,6 +12,9 @@ use embassy_nrf::wdt::{self, Watchdog};
 use embassy_sync::mutex::Mutex;
 use panic_reset as _;
 
+#[cfg(feature = "skip-include")]
+static APP_B: &[u8] = &[0, 1, 2, 3];
+#[cfg(not(feature = "skip-include"))]
 static APP_B: &[u8] = include_bytes!("../../b.bin");
 
 #[embassy_executor::main]
@@ -55,13 +58,13 @@ async fn main(_spawner: Spawner) {
         button.wait_for_any_edge().await;
         if button.is_low() {
             let mut offset = 0;
+            let mut magic = [0; 4];
             for chunk in APP_B.chunks(4096) {
                 let mut buf: [u8; 4096] = [0; 4096];
                 buf[..chunk.len()].copy_from_slice(chunk);
-                updater.write_firmware(offset, &buf).await.unwrap();
+                updater.write_firmware(&mut magic, offset, &buf).await.unwrap();
                 offset += chunk.len();
             }
-            let mut magic = [0; 4];
             updater.mark_updated(&mut magic).await.unwrap();
             led.set_high();
             cortex_m::peripheral::SCB::sys_reset();
diff --git a/examples/boot/application/rp/Cargo.toml b/examples/boot/application/rp/Cargo.toml
index 4a2c5dd8..007b6839 100644
--- a/examples/boot/application/rp/Cargo.toml
+++ b/examples/boot/application/rp/Cargo.toml
@@ -29,6 +29,7 @@ debug = [
     "embassy-boot-rp/defmt",
     "panic-probe"
 ]
+skip-include = []
 
 [profile.release]
 debug = true
diff --git a/examples/boot/application/rp/src/bin/a.rs b/examples/boot/application/rp/src/bin/a.rs
index 69850069..c8497494 100644
--- a/examples/boot/application/rp/src/bin/a.rs
+++ b/examples/boot/application/rp/src/bin/a.rs
@@ -18,7 +18,11 @@ use panic_probe as _;
 #[cfg(feature = "panic-reset")]
 use panic_reset as _;
 
+#[cfg(feature = "skip-include")]
+static APP_B: &[u8] = &[0, 1, 2, 3];
+#[cfg(not(feature = "skip-include"))]
 static APP_B: &[u8] = include_bytes!("../../b.bin");
+
 const FLASH_SIZE: usize = 2 * 1024 * 1024;
 
 #[embassy_executor::main]
@@ -43,7 +47,7 @@ async fn main(_s: Spawner) {
     let mut buf: AlignedBuffer<4096> = AlignedBuffer([0; 4096]);
     defmt::info!("preparing update");
     let writer = updater
-        .prepare_update()
+        .prepare_update(&mut buf.0[..1])
         .map_err(|e| defmt::warn!("E: {:?}", defmt::Debug2Format(&e)))
         .unwrap();
     defmt::info!("writer created, starting write");
diff --git a/examples/boot/application/stm32f3/Cargo.toml b/examples/boot/application/stm32f3/Cargo.toml
index 24abd90d..5b3faf8f 100644
--- a/examples/boot/application/stm32f3/Cargo.toml
+++ b/examples/boot/application/stm32f3/Cargo.toml
@@ -26,3 +26,4 @@ defmt = [
       "embassy-stm32/defmt",
       "embassy-boot-stm32/defmt",
 ]
+skip-include = []
diff --git a/examples/boot/application/stm32f3/src/bin/a.rs b/examples/boot/application/stm32f3/src/bin/a.rs
index c94676f0..c0a11d69 100644
--- a/examples/boot/application/stm32f3/src/bin/a.rs
+++ b/examples/boot/application/stm32f3/src/bin/a.rs
@@ -13,6 +13,9 @@ use embassy_stm32::gpio::{Input, Level, Output, Pull, Speed};
 use embassy_sync::mutex::Mutex;
 use panic_reset as _;
 
+#[cfg(feature = "skip-include")]
+static APP_B: &[u8] = &[0, 1, 2, 3];
+#[cfg(not(feature = "skip-include"))]
 static APP_B: &[u8] = include_bytes!("../../b.bin");
 
 #[embassy_executor::main]
@@ -31,13 +34,13 @@ async fn main(_spawner: Spawner) {
     let mut updater = FirmwareUpdater::new(config);
     button.wait_for_falling_edge().await;
     let mut offset = 0;
+    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     for chunk in APP_B.chunks(2048) {
         let mut buf: [u8; 2048] = [0; 2048];
         buf[..chunk.len()].copy_from_slice(chunk);
-        updater.write_firmware(offset, &buf).await.unwrap();
+        updater.write_firmware(magic.as_mut(), offset, &buf).await.unwrap();
         offset += chunk.len();
     }
-    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     updater.mark_updated(magic.as_mut()).await.unwrap();
     led.set_low();
     cortex_m::peripheral::SCB::sys_reset();
diff --git a/examples/boot/application/stm32f7/Cargo.toml b/examples/boot/application/stm32f7/Cargo.toml
index 529a01aa..b6a6f9cd 100644
--- a/examples/boot/application/stm32f7/Cargo.toml
+++ b/examples/boot/application/stm32f7/Cargo.toml
@@ -16,6 +16,7 @@ defmt = { version = "0.3", optional = true }
 defmt-rtt = { version = "0.4", optional = true }
 panic-reset = { version = "0.1.1" }
 embedded-hal = { version = "0.2.6" }
+embedded-storage = "0.3.0"
 
 cortex-m = { version = "0.7.6", features = ["inline-asm", "critical-section-single-core"] }
 cortex-m-rt = "0.7.0"
@@ -26,3 +27,4 @@ defmt = [
       "embassy-stm32/defmt",
       "embassy-boot-stm32/defmt",
 ]
+skip-include = []
diff --git a/examples/boot/application/stm32f7/src/bin/a.rs b/examples/boot/application/stm32f7/src/bin/a.rs
index fc2702c9..dea682a9 100644
--- a/examples/boot/application/stm32f7/src/bin/a.rs
+++ b/examples/boot/application/stm32f7/src/bin/a.rs
@@ -2,6 +2,8 @@
 #![no_main]
 #![feature(type_alias_impl_trait)]
 
+use core::cell::RefCell;
+
 #[cfg(feature = "defmt-rtt")]
 use defmt_rtt::*;
 use embassy_boot_stm32::{AlignedBuffer, BlockingFirmwareUpdater, FirmwareUpdaterConfig};
@@ -9,8 +11,13 @@ use embassy_executor::Spawner;
 use embassy_stm32::exti::ExtiInput;
 use embassy_stm32::flash::{Flash, WRITE_SIZE};
 use embassy_stm32::gpio::{Input, Level, Output, Pull, Speed};
+use embassy_sync::blocking_mutex::Mutex;
+use embedded_storage::nor_flash::NorFlash;
 use panic_reset as _;
 
+#[cfg(feature = "skip-include")]
+static APP_B: &[u8] = &[0, 1, 2, 3];
+#[cfg(not(feature = "skip-include"))]
 static APP_B: &[u8] = include_bytes!("../../b.bin");
 
 #[embassy_executor::main]
@@ -27,16 +34,16 @@ async fn main(_spawner: Spawner) {
 
     let config = FirmwareUpdaterConfig::from_linkerfile_blocking(&flash);
     let mut updater = BlockingFirmwareUpdater::new(config);
-    let mut writer = updater.prepare_update().unwrap();
+    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
+    let writer = updater.prepare_update(magic.as_mut()).unwrap();
     button.wait_for_rising_edge().await;
     let mut offset = 0;
     let mut buf = AlignedBuffer([0; 4096]);
     for chunk in APP_B.chunks(4096) {
         buf.as_mut()[..chunk.len()].copy_from_slice(chunk);
         writer.write(offset, buf.as_ref()).unwrap();
-        offset += chunk.len();
+        offset += chunk.len() as u32;
     }
-    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     updater.mark_updated(magic.as_mut()).unwrap();
     led.set_low();
     cortex_m::peripheral::SCB::sys_reset();
diff --git a/examples/boot/application/stm32h7/Cargo.toml b/examples/boot/application/stm32h7/Cargo.toml
index d7539a53..0a7e19b1 100644
--- a/examples/boot/application/stm32h7/Cargo.toml
+++ b/examples/boot/application/stm32h7/Cargo.toml
@@ -16,6 +16,7 @@ defmt = { version = "0.3", optional = true }
 defmt-rtt = { version = "0.4", optional = true }
 panic-reset = { version = "0.1.1" }
 embedded-hal = { version = "0.2.6" }
+embedded-storage = "0.3.0"
 
 cortex-m = { version = "0.7.6", features = ["inline-asm", "critical-section-single-core"] }
 cortex-m-rt = "0.7.0"
@@ -26,3 +27,4 @@ defmt = [
       "embassy-stm32/defmt",
       "embassy-boot-stm32/defmt",
 ]
+skip-include = []
diff --git a/examples/boot/application/stm32h7/src/bin/a.rs b/examples/boot/application/stm32h7/src/bin/a.rs
index 1a54464d..71917669 100644
--- a/examples/boot/application/stm32h7/src/bin/a.rs
+++ b/examples/boot/application/stm32h7/src/bin/a.rs
@@ -2,6 +2,8 @@
 #![no_main]
 #![feature(type_alias_impl_trait)]
 
+use core::cell::RefCell;
+
 #[cfg(feature = "defmt-rtt")]
 use defmt_rtt::*;
 use embassy_boot_stm32::{AlignedBuffer, BlockingFirmwareUpdater, FirmwareUpdaterConfig};
@@ -9,8 +11,13 @@ use embassy_executor::Spawner;
 use embassy_stm32::exti::ExtiInput;
 use embassy_stm32::flash::{Flash, WRITE_SIZE};
 use embassy_stm32::gpio::{Input, Level, Output, Pull, Speed};
+use embassy_sync::blocking_mutex::Mutex;
+use embedded_storage::nor_flash::NorFlash;
 use panic_reset as _;
 
+#[cfg(feature = "skip-include")]
+static APP_B: &[u8] = &[0, 1, 2, 3];
+#[cfg(not(feature = "skip-include"))]
 static APP_B: &[u8] = include_bytes!("../../b.bin");
 
 #[embassy_executor::main]
@@ -26,17 +33,17 @@ async fn main(_spawner: Spawner) {
     led.set_high();
 
     let config = FirmwareUpdaterConfig::from_linkerfile_blocking(&flash);
+    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     let mut updater = BlockingFirmwareUpdater::new(config);
-    let mut writer = updater.prepare_update().unwrap();
+    let writer = updater.prepare_update(magic.as_mut()).unwrap();
     button.wait_for_rising_edge().await;
     let mut offset = 0;
     let mut buf = AlignedBuffer([0; 4096]);
     for chunk in APP_B.chunks(4096) {
         buf.as_mut()[..chunk.len()].copy_from_slice(chunk);
         writer.write(offset, buf.as_ref()).unwrap();
-        offset += chunk.len();
+        offset += chunk.len() as u32;
     }
-    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     updater.mark_updated(magic.as_mut()).unwrap();
     led.set_low();
     cortex_m::peripheral::SCB::sys_reset();
diff --git a/examples/boot/application/stm32l0/Cargo.toml b/examples/boot/application/stm32l0/Cargo.toml
index e90da259..998df4dc 100644
--- a/examples/boot/application/stm32l0/Cargo.toml
+++ b/examples/boot/application/stm32l0/Cargo.toml
@@ -26,3 +26,4 @@ defmt = [
       "embassy-stm32/defmt",
       "embassy-boot-stm32/defmt",
 ]
+skip-include = []
diff --git a/examples/boot/application/stm32l0/src/bin/a.rs b/examples/boot/application/stm32l0/src/bin/a.rs
index 4033ac59..ce80056e 100644
--- a/examples/boot/application/stm32l0/src/bin/a.rs
+++ b/examples/boot/application/stm32l0/src/bin/a.rs
@@ -4,22 +4,26 @@
 
 #[cfg(feature = "defmt-rtt")]
 use defmt_rtt::*;
-use embassy_boot_stm32::{AlignedBuffer, FirmwareUpdater};
+use embassy_boot_stm32::{AlignedBuffer, FirmwareUpdater, FirmwareUpdaterConfig};
 use embassy_embedded_hal::adapter::BlockingAsync;
 use embassy_executor::Spawner;
 use embassy_stm32::exti::ExtiInput;
 use embassy_stm32::flash::{Flash, WRITE_SIZE};
 use embassy_stm32::gpio::{Input, Level, Output, Pull, Speed};
+use embassy_sync::mutex::Mutex;
 use embassy_time::{Duration, Timer};
 use panic_reset as _;
 
+#[cfg(feature = "skip-include")]
+static APP_B: &[u8] = &[0, 1, 2, 3];
+#[cfg(not(feature = "skip-include"))]
 static APP_B: &[u8] = include_bytes!("../../b.bin");
 
 #[embassy_executor::main]
 async fn main(_spawner: Spawner) {
     let p = embassy_stm32::init(Default::default());
     let flash = Flash::new_blocking(p.FLASH);
-    let mut flash = BlockingAsync::new(flash);
+    let flash = Mutex::new(BlockingAsync::new(flash));
 
     let button = Input::new(p.PB2, Pull::Up);
     let mut button = ExtiInput::new(button, p.EXTI2);
@@ -28,18 +32,19 @@ async fn main(_spawner: Spawner) {
 
     led.set_high();
 
-    let mut updater = FirmwareUpdater::default();
+    let config = FirmwareUpdaterConfig::from_linkerfile(&flash);
+    let mut updater = FirmwareUpdater::new(config);
     button.wait_for_falling_edge().await;
     let mut offset = 0;
+    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     for chunk in APP_B.chunks(128) {
         let mut buf: [u8; 128] = [0; 128];
         buf[..chunk.len()].copy_from_slice(chunk);
-        updater.write_firmware(offset, &buf, &mut flash, 128).await.unwrap();
+        updater.write_firmware(magic.as_mut(), offset, &buf).await.unwrap();
         offset += chunk.len();
     }
 
-    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
-    updater.mark_updated(&mut flash, magic.as_mut()).await.unwrap();
+    updater.mark_updated(magic.as_mut()).await.unwrap();
     led.set_low();
     Timer::after(Duration::from_secs(1)).await;
     cortex_m::peripheral::SCB::sys_reset();
diff --git a/examples/boot/application/stm32l1/Cargo.toml b/examples/boot/application/stm32l1/Cargo.toml
index 8ac0fac8..10b58c17 100644
--- a/examples/boot/application/stm32l1/Cargo.toml
+++ b/examples/boot/application/stm32l1/Cargo.toml
@@ -26,3 +26,4 @@ defmt = [
       "embassy-stm32/defmt",
       "embassy-boot-stm32/defmt",
 ]
+skip-include = []
diff --git a/examples/boot/application/stm32l1/src/bin/a.rs b/examples/boot/application/stm32l1/src/bin/a.rs
index 00ddda63..1e9bf3cb 100644
--- a/examples/boot/application/stm32l1/src/bin/a.rs
+++ b/examples/boot/application/stm32l1/src/bin/a.rs
@@ -10,9 +10,13 @@ use embassy_executor::Spawner;
 use embassy_stm32::exti::ExtiInput;
 use embassy_stm32::flash::{Flash, WRITE_SIZE};
 use embassy_stm32::gpio::{Input, Level, Output, Pull, Speed};
+use embassy_sync::mutex::Mutex;
 use embassy_time::{Duration, Timer};
 use panic_reset as _;
 
+#[cfg(feature = "skip-include")]
+static APP_B: &[u8] = &[0, 1, 2, 3];
+#[cfg(not(feature = "skip-include"))]
 static APP_B: &[u8] = include_bytes!("../../b.bin");
 
 #[embassy_executor::main]
@@ -31,15 +35,15 @@ async fn main(_spawner: Spawner) {
     let config = FirmwareUpdaterConfig::from_linkerfile(&flash);
     let mut updater = FirmwareUpdater::new(config);
     button.wait_for_falling_edge().await;
+    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     let mut offset = 0;
     for chunk in APP_B.chunks(128) {
         let mut buf: [u8; 128] = [0; 128];
         buf[..chunk.len()].copy_from_slice(chunk);
-        updater.write_firmware(offset, &buf).await.unwrap();
+        updater.write_firmware(magic.as_mut(), offset, &buf).await.unwrap();
         offset += chunk.len();
     }
 
-    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     updater.mark_updated(magic.as_mut()).await.unwrap();
     led.set_low();
     Timer::after(Duration::from_secs(1)).await;
diff --git a/examples/boot/application/stm32l4/Cargo.toml b/examples/boot/application/stm32l4/Cargo.toml
index ec79acde..713a6527 100644
--- a/examples/boot/application/stm32l4/Cargo.toml
+++ b/examples/boot/application/stm32l4/Cargo.toml
@@ -26,3 +26,4 @@ defmt = [
       "embassy-stm32/defmt",
       "embassy-boot-stm32/defmt",
 ]
+skip-include = []
diff --git a/examples/boot/application/stm32l4/src/bin/a.rs b/examples/boot/application/stm32l4/src/bin/a.rs
index 54579e4a..a514ab5b 100644
--- a/examples/boot/application/stm32l4/src/bin/a.rs
+++ b/examples/boot/application/stm32l4/src/bin/a.rs
@@ -10,8 +10,12 @@ use embassy_executor::Spawner;
 use embassy_stm32::exti::ExtiInput;
 use embassy_stm32::flash::{Flash, WRITE_SIZE};
 use embassy_stm32::gpio::{Input, Level, Output, Pull, Speed};
+use embassy_sync::mutex::Mutex;
 use panic_reset as _;
 
+#[cfg(feature = "skip-include")]
+static APP_B: &[u8] = &[0, 1, 2, 3];
+#[cfg(not(feature = "skip-include"))]
 static APP_B: &[u8] = include_bytes!("../../b.bin");
 
 #[embassy_executor::main]
@@ -29,15 +33,15 @@ async fn main(_spawner: Spawner) {
     let config = FirmwareUpdaterConfig::from_linkerfile(&flash);
     let mut updater = FirmwareUpdater::new(config);
     button.wait_for_falling_edge().await;
+    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     let mut offset = 0;
     for chunk in APP_B.chunks(2048) {
         let mut buf: [u8; 2048] = [0; 2048];
         buf[..chunk.len()].copy_from_slice(chunk);
-        updater.write_firmware(offset, &buf).await.unwrap();
+        updater.write_firmware(magic.as_mut(), offset, &buf).await.unwrap();
         offset += chunk.len();
     }
-    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
-    updater.mark_updated(&mut flash, magic.as_mut()).await.unwrap();
+    updater.mark_updated(magic.as_mut()).await.unwrap();
     led.set_low();
     cortex_m::peripheral::SCB::sys_reset();
 }
diff --git a/examples/boot/application/stm32wl/Cargo.toml b/examples/boot/application/stm32wl/Cargo.toml
index dfaece6c..4c8bbd73 100644
--- a/examples/boot/application/stm32wl/Cargo.toml
+++ b/examples/boot/application/stm32wl/Cargo.toml
@@ -26,3 +26,4 @@ defmt = [
       "embassy-stm32/defmt",
       "embassy-boot-stm32/defmt",
 ]
+skip-include = []
diff --git a/examples/boot/application/stm32wl/src/bin/a.rs b/examples/boot/application/stm32wl/src/bin/a.rs
index 0c6fa05f..52a197a5 100644
--- a/examples/boot/application/stm32wl/src/bin/a.rs
+++ b/examples/boot/application/stm32wl/src/bin/a.rs
@@ -4,21 +4,25 @@
 
 #[cfg(feature = "defmt-rtt")]
 use defmt_rtt::*;
-use embassy_boot_stm32::{AlignedBuffer, FirmwareUpdater};
+use embassy_boot_stm32::{AlignedBuffer, FirmwareUpdater, FirmwareUpdaterConfig};
 use embassy_embedded_hal::adapter::BlockingAsync;
 use embassy_executor::Spawner;
 use embassy_stm32::exti::ExtiInput;
 use embassy_stm32::flash::{Flash, WRITE_SIZE};
 use embassy_stm32::gpio::{Input, Level, Output, Pull, Speed};
+use embassy_sync::mutex::Mutex;
 use panic_reset as _;
 
+#[cfg(feature = "skip-include")]
+static APP_B: &[u8] = &[0, 1, 2, 3];
+#[cfg(not(feature = "skip-include"))]
 static APP_B: &[u8] = include_bytes!("../../b.bin");
 
 #[embassy_executor::main]
 async fn main(_spawner: Spawner) {
     let p = embassy_stm32::init(Default::default());
     let flash = Flash::new_blocking(p.FLASH);
-    let mut flash = Mutex::new(BlockingAsync::new(flash));
+    let flash = Mutex::new(BlockingAsync::new(flash));
 
     let button = Input::new(p.PA0, Pull::Up);
     let mut button = ExtiInput::new(button, p.EXTI0);
@@ -30,15 +34,15 @@ async fn main(_spawner: Spawner) {
     let mut updater = FirmwareUpdater::new(config);
     button.wait_for_falling_edge().await;
     //defmt::info!("Starting update");
+    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     let mut offset = 0;
     for chunk in APP_B.chunks(2048) {
         let mut buf: [u8; 2048] = [0; 2048];
         buf[..chunk.len()].copy_from_slice(chunk);
         //        defmt::info!("Writing chunk at 0x{:x}", offset);
-        updater.write_firmware(offset, &buf).await.unwrap();
+        updater.write_firmware(magic.as_mut(), offset, &buf).await.unwrap();
         offset += chunk.len();
     }
-    let mut magic = AlignedBuffer([0; WRITE_SIZE]);
     updater.mark_updated(magic.as_mut()).await.unwrap();
     //defmt::info!("Marked as updated");
     led.set_low();