diff --git a/.github/workflows/sim.yaml b/.github/workflows/sim.yaml
index df103ac..c76f7d4 100644
--- a/.github/workflows/sim.yaml
+++ b/.github/workflows/sim.yaml
@@ -14,21 +14,22 @@
         features:
         - "sig-ecdsa,sig-ecdsa-mbedtls,sig-ed25519,enc-kw,bootstrap"
         - "sig-rsa,sig-rsa3072,overwrite-only,validate-primary-slot,swap-move"
-        - "enc-rsa"
-        - "enc-aes256-rsa"
-        - "enc-ec256"
-        - "enc-aes256-ec256"
-        - "enc-x25519"
-        - "enc-aes256-x25519"
-        - "sig-rsa overwrite-only large-write,sig-ecdsa overwrite-only large-write,sig-ecdsa-mbedtls overwrite-only large-write,multiimage overwrite-only large-write"
+        - "enc-rsa,enc-rsa max-align-32"
+        - "enc-aes256-rsa,enc-aes256-rsa max-align-32"
+        - "enc-ec256,enc-ec256 max-align-32"
+        - "enc-aes256-ec256,enc-aes256-ec256 max-align-32"
+        - "enc-x25519,enc-x25519 max-align-32"
+        - "enc-aes256-x25519,enc-aes256-x25519 max-align-32"
+        - "sig-rsa overwrite-only,sig-ecdsa overwrite-only,sig-ecdsa-mbedtls overwrite-only,multiimage overwrite-only"
         - "sig-rsa validate-primary-slot,sig-ecdsa validate-primary-slot,sig-ecdsa-mbedtls validate-primary-slot,sig-rsa multiimage validate-primary-slot"
-        - "enc-kw overwrite-only large-write,enc-rsa overwrite-only large-write"
-        - "enc-aes256-kw overwrite-only large-write,enc-rsa overwrite-only large-write"
+        - "enc-kw overwrite-only,enc-kw overwrite-only max-align-32"
+        - "enc-rsa overwrite-only,enc-rsa overwrite-only max-align-32"
+        - "enc-aes256-kw overwrite-only,enc-aes256-kw overwrite-only max-align-32"
         - "sig-rsa enc-rsa validate-primary-slot,swap-move enc-rsa sig-rsa validate-primary-slot bootstrap"
         - "sig-rsa enc-kw validate-primary-slot bootstrap,sig-ed25519 enc-x25519 validate-primary-slot"
         - "sig-ecdsa enc-kw validate-primary-slot"
         - "sig-ecdsa-mbedtls enc-kw validate-primary-slot"
-        - "sig-rsa validate-primary-slot overwrite-only large-write"
+        - "sig-rsa validate-primary-slot overwrite-only,sig-rsa validate-primary-slot overwrite-only max-align-32"
         - "sig-ecdsa enc-ec256 validate-primary-slot"
         - "sig-ecdsa-mbedtls enc-ec256-mbedtls validate-primary-slot"
         - "sig-ecdsa-mbedtls enc-aes256-ec256 validate-primary-slot"
diff --git a/sim/Cargo.toml b/sim/Cargo.toml
index 5d5555e..856ccb2 100644
--- a/sim/Cargo.toml
+++ b/sim/Cargo.toml
@@ -28,8 +28,8 @@
 multiimage = ["mcuboot-sys/multiimage"]
 ram-load = ["mcuboot-sys/ram-load"]
 direct-xip = ["mcuboot-sys/direct-xip"]
-large-write = []
 downgrade-prevention = ["mcuboot-sys/downgrade-prevention"]
+max-align-32 = ["mcuboot-sys/max-align-32"]
 
 [dependencies]
 byteorder = "1.3"
diff --git a/sim/mcuboot-sys/Cargo.toml b/sim/mcuboot-sys/Cargo.toml
index 225ca0c..1f6b81c 100644
--- a/sim/mcuboot-sys/Cargo.toml
+++ b/sim/mcuboot-sys/Cargo.toml
@@ -80,9 +80,8 @@
 # Check (in software) against version downgrades.
 downgrade-prevention = []
 
-# Large write.  Not meaningful, but present here so that the
-# full-suite tests will work for this configuration.
-large-write = []
+# Support images with 32-byte maximum write alignment value.
+max-align-32 = []
 
 [build-dependencies]
 cc = "1.0.25"
diff --git a/sim/mcuboot-sys/build.rs b/sim/mcuboot-sys/build.rs
index eb3ab34..550d980 100644
--- a/sim/mcuboot-sys/build.rs
+++ b/sim/mcuboot-sys/build.rs
@@ -40,6 +40,13 @@
     conf.conf.define("MCUBOOT_USE_FLASH_AREA_GET_SECTORS", None);
     conf.conf.define("MCUBOOT_HAVE_ASSERT_H", None);
     conf.conf.define("MCUBOOT_MAX_IMG_SECTORS", Some("128"));
+
+#[cfg(not(feature = "max-align-32"))]
+    conf.conf.define("MCUBOOT_BOOT_MAX_ALIGN", Some("8"));
+
+#[cfg(feature = "max-align-32")]
+    conf.conf.define("MCUBOOT_BOOT_MAX_ALIGN", Some("32"));
+
     conf.conf.define("MCUBOOT_IMAGE_NUMBER", Some(if multiimage { "2" } else { "1" }));
 
     if downgrade_prevention && !overwrite_only {
diff --git a/sim/mcuboot-sys/csupport/run.c b/sim/mcuboot-sys/csupport/run.c
index 6c61228..cb2016b 100644
--- a/sim/mcuboot-sys/csupport/run.c
+++ b/sim/mcuboot-sys/csupport/run.c
@@ -477,5 +477,5 @@
 
 uint32_t boot_magic_sz(void)
 {
-    return BOOT_MAGIC_SZ;
+    return BOOT_MAGIC_ALIGN_SIZE;
 }
diff --git a/sim/src/image.rs b/sim/src/image.rs
index c7b9846..d3cc068 100644
--- a/sim/src/image.rs
+++ b/sim/src/image.rs
@@ -54,6 +54,7 @@
     UpgradeInfo,
 };
 use crate::tlv::{ManifestGen, TlvGen, TlvFlags};
+use crate::utils::align_up;
 use typenum::{U32, U16};
 
 /// For testing, use a non-zero offset for the ram-load, to make sure the offset is getting used
@@ -1522,7 +1523,8 @@
                 // c::boot_status_sz(dev.align() as u32) as usize
                 16 + 4 * dev.align()
             } else {
-                c::boot_trailer_sz(dev.align() as u32) as usize
+                let sector_size = dev.sector_iter().next().unwrap().size as u32;
+                align_up(c::boot_trailer_sz(dev.align() as u32), sector_size) as usize
             };
             let tlv_len = tlv.estimate_size();
             info!("slot: 0x{:x}, HDR: 0x{:x}, trailer: 0x{:x}",
@@ -1800,7 +1802,7 @@
 
     failed |= match magic {
         Some(v) => {
-            let magic_off = c::boot_max_align() * 3;
+            let magic_off = (c::boot_max_align() * 3) + (c::boot_magic_sz() - MAGIC.len());
             if v == 1 && &copy[magic_off..] != MAGIC {
                 warn!("\"magic\" mismatch at {:#x}", offset);
                 true
@@ -1937,11 +1939,18 @@
     pub dev_id: u8,
 }
 
+#[cfg(not(feature = "max-align-32"))]
 const MAGIC: &[u8] = &[0x77, 0xc2, 0x95, 0xf3,
                        0x60, 0xd2, 0xef, 0x7f,
                        0x35, 0x52, 0x50, 0x0f,
                        0x2c, 0xb6, 0x79, 0x80];
 
+#[cfg(feature = "max-align-32")]
+const MAGIC: &[u8] = &[0x20, 0x00, 0x2d, 0xe1,
+                       0x5d, 0x29, 0x41, 0x0b,
+                       0x8d, 0x77, 0x67, 0x9c,
+                       0x11, 0x0f, 0x1f, 0x8a];
+
 // Replicates defines found in bootutil.h
 const BOOT_MAGIC_GOOD: Option<u8> = Some(1);
 const BOOT_MAGIC_UNSET: Option<u8> = Some(3);
@@ -1958,8 +1967,9 @@
         // The write size is larger than the magic value.  Fill a buffer
         // with the erased value, put the MAGIC in it, and write it in its
         // entirety.
-        let mut buf = vec![dev.erased_val(); align];
-        buf[(offset % align)..].copy_from_slice(MAGIC);
+        let mut buf = vec![dev.erased_val(); c::boot_max_align()];
+        let magic_off = (offset % align) + (c::boot_magic_sz() - MAGIC.len());
+        buf[magic_off..].copy_from_slice(MAGIC);
         dev.write(offset - (offset % align), &buf).unwrap();
     } else {
         dev.write(offset, MAGIC).unwrap();
@@ -2024,12 +2034,12 @@
     }
 }
 
-#[cfg(not(feature = "large-write"))]
+#[cfg(not(feature = "max-align-32"))]
 fn test_alignments() -> &'static [usize] {
     &[1, 2, 4, 8]
 }
 
-#[cfg(feature = "large-write")]
+#[cfg(feature = "max-align-32")]
 fn test_alignments() -> &'static [usize] {
-    &[1, 2, 4, 8, 128, 512]
+    &[32]
 }
diff --git a/sim/src/lib.rs b/sim/src/lib.rs
index a491438..df1919e 100644
--- a/sim/src/lib.rs
+++ b/sim/src/lib.rs
@@ -16,6 +16,7 @@
 mod depends;
 mod image;
 mod tlv;
+mod utils;
 pub mod testlog;
 
 pub use crate::{
diff --git a/sim/src/utils.rs b/sim/src/utils.rs
new file mode 100644
index 0000000..abbac3c
--- /dev/null
+++ b/sim/src/utils.rs
@@ -0,0 +1,11 @@
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: Apache-2.0
+
+//! Utility functions used throughout MCUboot
+
+pub fn align_up(num: u32, align: u32) -> u32 {
+    assert!(align.is_power_of_two());
+
+    (num + (align - 1)) & !(align - 1)
+}