diff --git a/satrs-core/Cargo.toml b/satrs-core/Cargo.toml
index 66fb017..6424c01 100644
--- a/satrs-core/Cargo.toml
+++ b/satrs-core/Cargo.toml
@@ -64,7 +64,7 @@ optional = true
 # version = "0.5.4"
 # path = "../spacepackets"
 git = "https://egit.irs.uni-stuttgart.de/rust/spacepackets.git"
-rev = "28cd8c02ac0"
+rev = "4485ed26699d32"
 default-features = false
 
 [dev-dependencies]
diff --git a/satrs-core/src/pus/verification.rs b/satrs-core/src/pus/verification.rs
index 3c522e8..99a1c68 100644
--- a/satrs-core/src/pus/verification.rs
+++ b/satrs-core/src/pus/verification.rs
@@ -233,7 +233,7 @@ impl TryFrom<TcStateToken> for VerificationToken<TcStateAccepted> {
         if let TcStateToken::Accepted(token) = value {
             Ok(token)
         } else {
-            return Err(());
+            Err(())
         }
     }
 }
diff --git a/satrs-example/src/main.rs b/satrs-example/src/main.rs
index 0f7ad9c..2e830f0 100644
--- a/satrs-example/src/main.rs
+++ b/satrs-example/src/main.rs
@@ -6,7 +6,6 @@ mod requests;
 mod tmtc;
 
 use log::{info, warn};
-use std::collections::hash_map::Entry;
 
 use crate::hk::AcsHkIds;
 use crate::logging::setup_logger;
@@ -38,7 +37,7 @@ use satrs_core::pus::verification::{
 };
 use satrs_core::pus::MpscTmtcInStoreSender;
 use satrs_core::seq_count::{SeqCountProviderSimple, SequenceCountProviderCore};
-use satrs_core::spacepackets::ecss::{PusPacket, SerializablePusPacket};
+use satrs_core::spacepackets::tm::PusTmZeroCopyWriter;
 use satrs_core::spacepackets::{
     time::cds::TimeProvider,
     time::TimeWriter,
@@ -213,38 +212,35 @@ fn main() {
     let jh1 = thread::Builder::new()
         .name("TM Funnel".to_string())
         .spawn(move || {
-            let mut tm_buf: [u8; 2048] = [0; 2048];
             let tm_funnel = TmFunnel {
                 tm_server_tx,
                 tm_funnel_rx,
             };
             loop {
                 if let Ok(addr) = tm_funnel.tm_funnel_rx.recv() {
-                    // Read the TM, set sequence counter and message counter, and finally write
-                    // it back with the updated CRC.
-                    // We could theoretically manipulate the counters and the CRC directly
-                    // in place as an optimization, but I don't think this is necessary..
+                    // Read the TM, set sequence counter and message counter, and finally update
+                    // the CRC.
                     let shared_pool = tm_store.backing_pool();
                     let mut pool_guard = shared_pool.write().expect("Locking TM pool failed");
                     let tm_raw = pool_guard
                         .modify(&addr)
                         .expect("Reading TM from pool failed");
-                    tm_buf[0..tm_raw.len()].copy_from_slice(&tm_raw);
-                    let (mut tm, size) =
-                        PusTm::from_bytes(&tm_buf, 7).expect("Creating TM from raw slice failed");
-                    tm.sp_header.set_apid(PUS_APID);
-                    tm.sp_header
-                        .set_seq_count(seq_count_provider.get_and_increment());
-                    let entry = msg_counter_map.entry(tm.service()).or_insert(0);
-                    tm.sec_header.msg_counter = *entry;
+                    let mut zero_copy_writer = PusTmZeroCopyWriter::new(tm_raw)
+                        .expect("Creating TM zero copy writer failed");
+                    zero_copy_writer.set_apid(PUS_APID);
+                    zero_copy_writer.set_seq_count(seq_count_provider.get_and_increment());
+                    let entry = msg_counter_map
+                        .entry(zero_copy_writer.service())
+                        .or_insert(0);
+                    zero_copy_writer.set_msg_count(*entry);
                     if *entry == u16::MAX {
                         *entry = 0;
                     } else {
                         *entry += 1;
                     }
-                    tm.calc_crc_on_serialization = true;
-                    tm.write_to_bytes(tm_raw)
-                        .expect("Writing PUS TM back failed");
+
+                    // This operation has to come last!
+                    zero_copy_writer.finish();
                     tm_funnel
                         .tm_server_tx
                         .send(addr)
diff --git a/satrs-example/src/pus/scheduler.rs b/satrs-example/src/pus/scheduler.rs
index ffd8c89..35c84b8 100644
--- a/satrs-example/src/pus/scheduler.rs
+++ b/satrs-example/src/pus/scheduler.rs
@@ -1,6 +1,5 @@
 use crate::tmtc::PusTcSource;
 use log::{error, info, warn};
-use satrs_core::pool::{SharedPool, StoreAddr};
 use satrs_core::pus::scheduler::TcInfo;
 use satrs_core::pus::scheduler_srv::PusService11SchedHandler;
 use satrs_core::pus::{PusPacketHandlerResult, PusServiceHandler};