diff --git a/Cargo.lock b/Cargo.lock
index 5d4f7b3..ce27b6a 100755
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -481,7 +481,7 @@ checksum = "ac6b926516df9c60bfa16e107b21086399f8285a44ca9711344b9e553c5146e2"
 
 [[package]]
 name = "depot"
-version = "0.60.0"
+version = "1.0.0"
 dependencies = [
  "anyhow",
  "ar",
@@ -1417,9 +1417,9 @@ dependencies = [
 
 [[package]]
 name = "md5"
-version = "0.8.0"
+version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ae960838283323069879657ca3de837e9f7bbb4c7bf6ea7f1b290d5e9476d2e0"
+checksum = "7ebb8d8732c6a6df3d8f032a82911cfc747e00efb95cc46e8d0acd5b5b88570c"
 
 [[package]]
 name = "memchr"
diff --git a/Cargo.toml b/Cargo.toml
index a049978..3f79335 100755
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "depot"
-version = "0.60.0"
+version = "1.0.0"
 edition = "2024"
 
 [lints.rust]
@@ -42,7 +42,7 @@ xz2 = "0.1.7"
 zip = "8.5.0"
 zstd = { version = "0.13.3", features = ["zstdmt"] }
 inquire = "0.9.4"
-md5 = "0.8.0"
+md5 = "0.8.1"
 suppaftp = "10.0.0"
 minisign = "0.9.1"
 petgraph = "0.8.3"
diff --git a/src/commands.rs b/src/commands.rs
index 6539239..8d53a50 100644
--- a/src/commands.rs
+++ b/src/commands.rs
@@ -9,7 +9,7 @@ use crate::{
 };
 use anyhow::{Context, Result};
 use git2::Direction;
-use indicatif::{ProgressBar, ProgressDrawTarget, ProgressStyle};
+use indicatif::{MultiProgress, ProgressBar, ProgressDrawTarget, ProgressStyle};
 use std::cmp::Ordering;
 use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
 use std::fs;
@@ -23,6 +23,8 @@ use std::time::Duration;
 use url::Url;
 use walkdir::WalkDir;
 
+const MAX_PARALLEL_DOWNLOADS: usize = 8;
+
 use build_cmd::support::{
     automatic_tests_disabled_for_outputs, build_lib32_companion_package, clean_build_source_dirs,
     clean_build_workspace, effective_lib32_only, ensure_requested_development_package_installed,
@@ -1426,26 +1428,24 @@ fn install_planned_packages_to_rootfs_with_pre_removed(
     Ok(())
 }
 
-fn run_parallel_verification<T, F>(items: &[T], progress: &ProgressBar, verify: F) -> Result<()>
+fn run_parallel_tasks<T, U, F>(items: &[T], worker_count: usize, task: F) -> Result<Vec<U>>
 where
     T: Sync,
-    F: Fn(&T) -> Result<()> + Sync,
+    U: Send,
+    F: Fn(usize, &T) -> Result<U> + Sync,
 {
     if items.is_empty() {
-        return Ok(());
+        return Ok(Vec::new());
     }
 
-    let worker_count = std::thread::available_parallelism()
-        .map(|count| count.get())
-        .unwrap_or(1)
-        .min(items.len());
+    let worker_count = worker_count.max(1).min(items.len());
     let next_index = AtomicUsize::new(0);
     let (sender, receiver) = mpsc::channel();
 
-    std::thread::scope(|scope| -> Result<()> {
+    std::thread::scope(|scope| -> Result<Vec<U>> {
         for _ in 0..worker_count {
             let sender = sender.clone();
-            let verify = &verify;
+            let task = &task;
             let next_index = &next_index;
             scope.spawn(move || {
                 loop {
@@ -1453,7 +1453,7 @@ where
                     if index >= items.len() {
                         break;
                     }
-                    let result = verify(&items[index]);
+                    let result = task(index, &items[index]);
                     if sender.send((index, result)).is_err() {
                         break;
                     }
@@ -1462,22 +1462,37 @@ where
         }
         drop(sender);
 
-        let mut results: Vec<Option<Result<()>>> = (0..items.len()).map(|_| None).collect();
+        let mut results: Vec<Option<Result<U>>> = (0..items.len()).map(|_| None).collect();
         for _ in 0..items.len() {
             let (index, result) = receiver
                 .recv()
-                .context("Verification worker exited before reporting a result")?;
+                .context("Parallel worker exited before reporting a result")?;
             results[index] = Some(result);
-            progress.inc(1);
         }
 
-        for result in results {
-            result.expect("every verification item must report a result")?;
-        }
-        Ok(())
+        results
+            .into_iter()
+            .map(|result| result.expect("every parallel item must report a result"))
+            .collect()
     })
 }
 
+fn run_parallel_verification<T, F>(items: &[T], progress: &ProgressBar, verify: F) -> Result<()>
+where
+    T: Sync,
+    F: Fn(&T) -> Result<()> + Sync,
+{
+    let worker_count = std::thread::available_parallelism()
+        .map(|count| count.get())
+        .unwrap_or(1);
+    run_parallel_tasks(items, worker_count, |_, item| {
+        let result = verify(item);
+        progress.inc(1);
+        result
+    })?;
+    Ok(())
+}
+
 #[cfg(test)]
 fn install_package_outputs_to_rootfs(
     pkg_spec: &package::PackageSpec,
@@ -1775,8 +1790,11 @@ fn execute_install_plan_with_child_commands(
     let mut binary_archives: HashMap<(String, String), db::repo::BinaryRepoCachedArchive> =
         HashMap::new();
     let mut binary_phase_items = Vec::new();
+    let mut seen_binary_archives = HashSet::new();
     for step in &actionable_steps {
-        if let planner::PlanOrigin::Binary { repo_name, record } = &step.origin {
+        if let planner::PlanOrigin::Binary { repo_name, record } = &step.origin
+            && seen_binary_archives.insert((repo_name.clone(), record.filename.clone()))
+        {
             binary_phase_items.push(BinaryPhaseItem {
                 repo_name: repo_name.clone(),
                 record: (**record).clone(),
@@ -1790,53 +1808,72 @@ fn execute_install_plan_with_child_commands(
             binary_phase_items.len()
         ));
         let use_tty_progress = std::io::stderr().is_terminal();
-        for item in &binary_phase_items {
-            let label = format!(
-                "{}-{}-{}",
-                item.record.name,
-                item.record.version,
-                binary_arch_from_filename(&item.record.filename)
-            );
-            let pb = ProgressBar::new(item.record.size.max(1));
-            pb.set_draw_target(if use_tty_progress {
-                ProgressDrawTarget::stderr()
-            } else {
-                ProgressDrawTarget::hidden()
-            });
-            pb.set_style(
-                ProgressStyle::default_bar()
-                    .template("{prefix:.bold} [{bar:40.cyan/blue}] {eta}")
-                    .unwrap_or_else(|_| ProgressStyle::default_bar())
-                    .progress_chars("#>-"),
-            );
-            pb.set_prefix(label);
-
-            let repo_cfg = config
-                .binary_repos
-                .get(&item.repo_name)
-                .with_context(|| format!("Binary repo '{}' not found in config", item.repo_name))?;
-            let mut progress_cb = |downloaded: u64, total: Option<u64>| {
-                if let Some(t) = total
-                    && t > 0
-                {
-                    pb.set_length(t);
-                }
-                pb.set_position(downloaded);
-            };
-            let cached = db::repo::cache_binary_package_archive_with_progress(
-                &item.repo_name,
-                repo_cfg,
-                &item.record,
-                &config.package_cache_dir,
-                Some(&mut progress_cb),
-            )
-            .with_context(|| {
-                format!(
-                    "Failed to cache binary package '{}' from repo '{}'",
-                    item.record.filename, item.repo_name
-                )
-            })?;
-            pb.finish_and_clear();
+        let download_progress = MultiProgress::with_draw_target(if use_tty_progress {
+            ProgressDrawTarget::stderr()
+        } else {
+            ProgressDrawTarget::hidden()
+        });
+        let download_bars = binary_phase_items
+            .iter()
+            .map(|item| {
+                let label = format!(
+                    "{}-{}-{}",
+                    item.record.name,
+                    item.record.version,
+                    binary_arch_from_filename(&item.record.filename)
+                );
+                let pb = download_progress.add(ProgressBar::new(item.record.size.max(1)));
+                pb.set_style(
+                    ProgressStyle::default_bar()
+                        .template("{prefix:.bold} [{bar:40.cyan/blue}] {eta}")
+                        .unwrap_or_else(|_| ProgressStyle::default_bar())
+                        .progress_chars("#>-"),
+                );
+                pb.set_prefix(label);
+                pb
+            })
+            .collect::<Vec<_>>();
+        let download_client = db::repo::binary_package_http_client()?;
+        let download_results = run_parallel_tasks(
+            &binary_phase_items,
+            MAX_PARALLEL_DOWNLOADS,
+            |index, item| {
+                let pb = &download_bars[index];
+                let mut progress_cb = |downloaded: u64, total: Option<u64>| {
+                    if let Some(t) = total
+                        && t > 0
+                    {
+                        pb.set_length(t);
+                    }
+                    pb.set_position(downloaded);
+                };
+                let result = (|| {
+                    let repo_cfg = config.binary_repos.get(&item.repo_name).with_context(|| {
+                        format!("Binary repo '{}' not found in config", item.repo_name)
+                    })?;
+                    db::repo::cache_binary_package_archive_with_client_and_progress(
+                        &item.repo_name,
+                        repo_cfg,
+                        &item.record,
+                        &config.package_cache_dir,
+                        &download_client,
+                        Some(&mut progress_cb),
+                    )
+                    .with_context(|| {
+                        format!(
+                            "Failed to cache binary package '{}' from repo '{}'",
+                            item.record.filename, item.repo_name
+                        )
+                    })
+                })();
+                pb.finish_and_clear();
+                result
+            },
+        );
+        download_progress
+            .clear()
+            .context("Failed to clear binary download progress")?;
+        for (item, cached) in binary_phase_items.iter().zip(download_results?) {
             binary_archives.insert(
                 (item.repo_name.clone(), item.record.filename.clone()),
                 cached,
@@ -1844,59 +1881,34 @@ fn execute_install_plan_with_child_commands(
         }
 
         ui::info(format!(
-            "Verifying checksums for {} binary package(s)...",
+            "Verifying checksums and detached signatures for {} binary package(s)...",
             binary_phase_items.len()
         ));
-        let checksum_pb = ProgressBar::new(binary_phase_items.len() as u64);
-        checksum_pb.set_draw_target(if use_tty_progress {
+        let integrity_pb = ProgressBar::new(binary_phase_items.len() as u64);
+        integrity_pb.set_draw_target(if use_tty_progress {
             ProgressDrawTarget::stderr()
         } else {
             ProgressDrawTarget::hidden()
         });
-        checksum_pb.set_style(
+        integrity_pb.set_style(
             ProgressStyle::default_bar()
                 .template("{prefix:.bold} [{bar:40.cyan/blue}] {pos}/{len} {eta}")
                 .unwrap_or_else(|_| ProgressStyle::default_bar())
                 .progress_chars("#>-"),
         );
-        checksum_pb.set_prefix("checksums");
-        run_parallel_verification(&binary_phase_items, &checksum_pb, |item| {
-            let cached = binary_archives
+        integrity_pb.set_prefix("integrity");
+        let has_detached_signatures = binary_phase_items.iter().any(|item| {
+            binary_archives
                 .get(&(item.repo_name.clone(), item.record.filename.clone()))
-                .with_context(|| {
-                    format!(
-                        "Cached archive missing for {} from repo '{}'",
-                        item.record.filename, item.repo_name
-                    )
-                })?;
-            db::repo::verify_binary_package_archive_checksums(&cached.package_path, &item.record)
-                .with_context(|| {
-                    format!(
-                        "Checksum verification failed for {} from repo '{}'",
-                        item.record.filename, item.repo_name
-                    )
-                })
-        })?;
-        checksum_pb.finish_and_clear();
-
-        ui::info(format!(
-            "Verifying detached signatures for {} binary package(s)...",
-            binary_phase_items.len()
-        ));
-        let signature_pb = ProgressBar::new(binary_phase_items.len() as u64);
-        signature_pb.set_draw_target(if use_tty_progress {
-            ProgressDrawTarget::stderr()
-        } else {
-            ProgressDrawTarget::hidden()
+                .is_some_and(|cached| cached.signature_path.exists())
         });
-        signature_pb.set_style(
-            ProgressStyle::default_bar()
-                .template("{prefix:.bold} [{bar:40.cyan/blue}] {pos}/{len} {eta}")
-                .unwrap_or_else(|_| ProgressStyle::default_bar())
-                .progress_chars("#>-"),
-        );
-        signature_pb.set_prefix("signatures");
-        run_parallel_verification(&binary_phase_items, &signature_pb, |item| {
+        let trusted_keys = if has_detached_signatures {
+            signing::load_trusted_public_keys(rootfs)
+                .context("Failed to load trusted Minisign public keys")?
+        } else {
+            Vec::new()
+        };
+        run_parallel_verification(&binary_phase_items, &integrity_pb, |item| {
             let repo_cfg = config
                 .binary_repos
                 .get(&item.repo_name)
@@ -1909,21 +1921,22 @@ fn execute_install_plan_with_child_commands(
                         item.record.filename, item.repo_name
                     )
                 })?;
-            db::repo::verify_binary_package_archive_signature(
+            db::repo::verify_binary_package_archive_integrity_with_trusted_keys(
                 &item.repo_name,
                 repo_cfg,
-                rootfs,
+                &item.record,
                 &cached.package_path,
                 &cached.signature_path,
+                &trusted_keys,
             )
             .with_context(|| {
                 format!(
-                    "Detached signature verification failed for {} from repo '{}'",
+                    "Integrity verification failed for {} from repo '{}'",
                     item.record.filename, item.repo_name
                 )
             })
         })?;
-        signature_pb.finish_and_clear();
+        integrity_pb.finish_and_clear();
     }
 
     if should_delegate_live_rootfs_installs(rootfs) {
diff --git a/src/commands/tests.rs b/src/commands/tests.rs
index b18ff1d..cf19b44 100644
--- a/src/commands/tests.rs
+++ b/src/commands/tests.rs
@@ -7,7 +7,7 @@ use crate::test_support::TestEnv;
 use git2::{Oid, Repository};
 use std::path::Path;
 use std::sync::{
-    Mutex, MutexGuard,
+    Barrier, Mutex, MutexGuard,
     atomic::{AtomicUsize, Ordering as AtomicOrdering},
 };
 
@@ -107,6 +107,20 @@ fn parallel_verification_processes_every_item() -> Result<()> {
     Ok(())
 }
 
+#[test]
+fn parallel_tasks_run_concurrently_and_preserve_input_order() -> Result<()> {
+    let items = vec![3_u8, 1, 4, 2];
+    let barrier = Barrier::new(items.len());
+
+    let results = run_parallel_tasks(&items, items.len(), |_, item| {
+        barrier.wait();
+        Ok(item * 2)
+    })?;
+
+    assert_eq!(results, vec![6, 2, 8, 4]);
+    Ok(())
+}
+
 #[test]
 fn install_post_extract_env_uses_selected_non_live_rootfs() -> Result<()> {
     let _guard = assume_yes_test_lock();
diff --git a/src/db/repo.rs b/src/db/repo.rs
index 186e8db..83d2f03 100644
--- a/src/db/repo.rs
+++ b/src/db/repo.rs
@@ -6,7 +6,7 @@ use rusqlite::{Connection, params};
 use sha2::{Digest, Sha256, Sha512};
 use std::collections::{BTreeSet, HashMap};
 use std::fs;
-use std::io::{Read, Write};
+use std::io::{Read, Seek, SeekFrom, Write};
 use std::path::{Path, PathBuf};
 use std::sync::{
     Mutex, OnceLock,
@@ -988,26 +988,11 @@ fn verify_with_any_trusted_public_key(
     input: &Path,
     sig_path: &Path,
 ) -> Result<PathBuf> {
-    let keys = crate::signing::list_trusted_public_keys(rootfs)?;
+    let keys = crate::signing::load_trusted_public_keys(rootfs)?;
     if keys.is_empty() {
         anyhow::bail!("No trusted minisign public keys found in rootfs or host");
     }
-
-    let mut last_failure: Option<(PathBuf, anyhow::Error)> = None;
-    for key_path in keys {
-        match crate::signing::verify_zst_file_detached_with_public_key(input, sig_path, &key_path) {
-            Ok(()) => return Ok(key_path),
-            Err(err) => last_failure = Some((key_path, err)),
-        }
-    }
-
-    let (key_path, err) = last_failure.expect("non-empty key list must produce a failure");
-    Err(err).with_context(|| {
-        format!(
-            "Detached signature verification failed with all trusted public keys (last tried {})",
-            key_path.display()
-        )
-    })
+    crate::signing::verify_zst_file_detached_with_trusted_keys(input, sig_path, &keys)
 }
 
 fn sanitize_filename_component(input: &str) -> String {
@@ -2199,16 +2184,7 @@ fn verify_binary_package_record_checksums(
     path: &Path,
     rec: &BinaryRepoPackageRecord,
 ) -> Result<()> {
-    use sha2::{Digest, Sha512};
-
-    let expected = rec.sha512.trim().to_ascii_lowercase();
-    if expected.is_empty() {
-        anyhow::bail!(
-            "Missing SHA-512 checksum for {} from repo '{}'",
-            path.display(),
-            rec.repo_name
-        );
-    }
+    let expected = expected_binary_package_sha512(path, rec)?;
 
     let mut file =
         fs::File::open(path).with_context(|| format!("Failed to open {}", path.display()))?;
@@ -2222,7 +2198,33 @@ fn verify_binary_package_record_checksums(
         hasher.update(&buf[..n]);
     }
 
-    if crate::hex::encode_lower(hasher.finalize()) != expected {
+    verify_binary_package_sha512_digest(
+        path,
+        rec,
+        &expected,
+        &crate::hex::encode_lower(hasher.finalize()),
+    )
+}
+
+fn expected_binary_package_sha512(path: &Path, rec: &BinaryRepoPackageRecord) -> Result<String> {
+    let expected = rec.sha512.trim().to_ascii_lowercase();
+    if expected.is_empty() {
+        anyhow::bail!(
+            "Missing SHA-512 checksum for {} from repo '{}'",
+            path.display(),
+            rec.repo_name
+        );
+    }
+    Ok(expected)
+}
+
+fn verify_binary_package_sha512_digest(
+    path: &Path,
+    rec: &BinaryRepoPackageRecord,
+    expected: &str,
+    actual: &str,
+) -> Result<()> {
+    if actual != expected {
         anyhow::bail!(
             "SHA-512 mismatch for {} from repo '{}'",
             path.display(),
@@ -2232,6 +2234,48 @@ fn verify_binary_package_record_checksums(
     Ok(())
 }
 
+struct Sha512Reader<R> {
+    inner: R,
+    hasher: Sha512,
+}
+
+impl<R> Sha512Reader<R> {
+    fn new(inner: R) -> Self {
+        Self {
+            inner,
+            hasher: Sha512::new(),
+        }
+    }
+
+    fn finalize_hex(self) -> String {
+        crate::hex::encode_lower(self.hasher.finalize())
+    }
+}
+
+impl<R: Read> Read for Sha512Reader<R> {
+    fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
+        let read = self.inner.read(buf)?;
+        if read > 0 {
+            self.hasher.update(&buf[..read]);
+        }
+        Ok(read)
+    }
+}
+
+impl<R: Seek> Seek for Sha512Reader<R> {
+    fn seek(&mut self, position: SeekFrom) -> std::io::Result<u64> {
+        if position != SeekFrom::Start(0) {
+            return Err(std::io::Error::new(
+                std::io::ErrorKind::Unsupported,
+                "checksum reader only supports rewinding to the start",
+            ));
+        }
+        let position = self.inner.seek(position)?;
+        self.hasher = Sha512::new();
+        Ok(position)
+    }
+}
+
 fn download_binary_package_archive(
     client: &reqwest::blocking::Client,
     pkg_url: &str,
@@ -2312,12 +2356,12 @@ fn fetch_binary_package_signature(
     Ok(found)
 }
 
-fn verify_binary_package_signature(
+fn verify_binary_package_signature_with_trusted_keys(
     repo_name: &str,
     repo: &crate::config::BinaryRepo,
-    rootfs: &Path,
     pkg_path: &Path,
     sig_path: &Path,
+    trusted_keys: &[crate::signing::TrustedPublicKey],
 ) -> Result<()> {
     if !sig_path.exists() {
         if repo.allow_unsigned {
@@ -2329,7 +2373,6 @@ fn verify_binary_package_signature(
         );
     }
 
-    let trusted_keys = crate::signing::list_trusted_public_keys(rootfs)?;
     if trusted_keys.is_empty() {
         if repo.allow_unsigned {
             crate::log_warn!(
@@ -2344,13 +2387,17 @@ fn verify_binary_package_signature(
         );
     }
 
-    let _verified_key = verify_with_any_trusted_public_key(rootfs, pkg_path, sig_path)
-        .with_context(|| {
-            format!(
-                "Failed to verify detached package signature for {}",
-                pkg_path.display()
-            )
-        })?;
+    let _verified_key = crate::signing::verify_zst_file_detached_with_trusted_keys(
+        pkg_path,
+        sig_path,
+        trusted_keys,
+    )
+    .with_context(|| {
+        format!(
+            "Failed to verify detached package signature for {}",
+            pkg_path.display()
+        )
+    })?;
     Ok(())
 }
 
@@ -2373,6 +2420,31 @@ pub fn cache_binary_package_archive_with_progress(
     repo: &crate::config::BinaryRepo,
     rec: &BinaryRepoPackageRecord,
     package_cache_dir: &Path,
+    progress_cb: Option<&mut dyn FnMut(u64, Option<u64>)>,
+) -> Result<BinaryRepoCachedArchive> {
+    let client = binary_package_http_client()?;
+    cache_binary_package_archive_with_client_and_progress(
+        repo_name,
+        repo,
+        rec,
+        package_cache_dir,
+        &client,
+        progress_cb,
+    )
+}
+
+pub(crate) fn binary_package_http_client() -> Result<reqwest::blocking::Client> {
+    reqwest::blocking::Client::builder()
+        .build()
+        .context("Failed to build HTTP client for binary package fetch")
+}
+
+pub(crate) fn cache_binary_package_archive_with_client_and_progress(
+    repo_name: &str,
+    repo: &crate::config::BinaryRepo,
+    rec: &BinaryRepoPackageRecord,
+    package_cache_dir: &Path,
+    client: &reqwest::blocking::Client,
     mut progress_cb: Option<&mut dyn FnMut(u64, Option<u64>)>,
 ) -> Result<BinaryRepoCachedArchive> {
     let machine_arch = std::env::consts::ARCH;
@@ -2393,12 +2465,8 @@ pub fn cache_binary_package_archive_with_progress(
     let pkg_url = join_repo_url(base_url, &rec.filename)?;
     let sig_url = join_repo_url(base_url, &format!("{}.sig", rec.filename))?;
 
-    let client = reqwest::blocking::Client::builder()
-        .build()
-        .context("Failed to build HTTP client for binary package fetch")?;
-
     let package_downloaded = if !package_path.exists() {
-        download_binary_package_archive(&client, &pkg_url, &tmp_path, &mut progress_cb)?;
+        download_binary_package_archive(client, &pkg_url, &tmp_path, &mut progress_cb)?;
         fs::rename(&tmp_path, &package_path).with_context(|| {
             format!(
                 "Failed to move {} to {}",
@@ -2419,7 +2487,7 @@ pub fn cache_binary_package_archive_with_progress(
 
     if package_downloaded || !signature_path.exists() {
         let sig_downloaded =
-            fetch_binary_package_signature(repo_name, repo, &client, &sig_url, &tmp_sig_path)?;
+            fetch_binary_package_signature(repo_name, repo, client, &sig_url, &tmp_sig_path)?;
         if sig_downloaded {
             fs::rename(&tmp_sig_path, &signature_path).with_context(|| {
                 format!(
@@ -2448,15 +2516,44 @@ pub fn verify_binary_package_archive_checksums(
     verify_binary_package_record_checksums(archive_path, rec)
 }
 
-/// Verify a cached/downloaded package archive against its detached signature.
-pub fn verify_binary_package_archive_signature(
+pub(crate) fn verify_binary_package_archive_integrity_with_trusted_keys(
     repo_name: &str,
     repo: &crate::config::BinaryRepo,
-    rootfs: &Path,
+    record: &BinaryRepoPackageRecord,
     package_path: &Path,
     signature_path: &Path,
+    trusted_keys: &[crate::signing::TrustedPublicKey],
 ) -> Result<()> {
-    verify_binary_package_signature(repo_name, repo, rootfs, package_path, signature_path)
+    if signature_path.exists() && !trusted_keys.is_empty() {
+        let expected = expected_binary_package_sha512(package_path, record)?;
+        let file = fs::File::open(package_path)
+            .with_context(|| format!("Failed to open {}", package_path.display()))?;
+        let mut reader = Sha512Reader::new(file);
+        let _verified_key = crate::signing::verify_reader_detached_with_trusted_keys(
+            &mut reader,
+            package_path,
+            signature_path,
+            trusted_keys,
+        )
+        .with_context(|| {
+            format!(
+                "Failed to verify detached package signature for {}",
+                package_path.display()
+            )
+        })?;
+        let actual = reader.finalize_hex();
+        verify_binary_package_sha512_digest(package_path, record, &expected, &actual)?;
+        return Ok(());
+    }
+
+    verify_binary_package_archive_checksums(package_path, record)?;
+    verify_binary_package_signature_with_trusted_keys(
+        repo_name,
+        repo,
+        package_path,
+        signature_path,
+        trusted_keys,
+    )
 }
 
 /// Download a binary package archive and verify it against detached signatures
@@ -2469,22 +2566,22 @@ pub fn fetch_binary_package_archive(
     package_cache_dir: &Path,
 ) -> Result<PathBuf> {
     let cached = cache_binary_package_archive(repo_name, repo, rec, package_cache_dir)?;
-    verify_binary_package_archive_checksums(&cached.package_path, rec).with_context(|| {
-        format!(
-            "Binary package failed checksum verification: {}",
-            cached.package_path.display()
-        )
-    })?;
-    verify_binary_package_archive_signature(
+    let trusted_keys = if cached.signature_path.exists() {
+        crate::signing::load_trusted_public_keys(rootfs)?
+    } else {
+        Vec::new()
+    };
+    verify_binary_package_archive_integrity_with_trusted_keys(
         repo_name,
         repo,
-        rootfs,
+        rec,
         &cached.package_path,
         &cached.signature_path,
+        &trusted_keys,
     )
     .with_context(|| {
         format!(
-            "Binary package failed signature verification: {}",
+            "Binary package failed integrity verification: {}",
             cached.package_path.display()
         )
     })?;
@@ -3239,7 +3336,7 @@ revision = 1
     }
 
     #[test]
-    fn test_cache_binary_package_archive_supports_phased_verification() {
+    fn test_cache_binary_package_archive_supports_combined_integrity_verification() {
         let rootfs = tempfile::tempdir().unwrap();
         let repo_dir = tempfile::tempdir().unwrap();
         let cache_dir = tempfile::tempdir().unwrap();
@@ -3286,14 +3383,29 @@ revision = 1
 
         verify_binary_package_archive_checksums(&cached.package_path, &rec)
             .expect("checksum verification should succeed");
-        verify_binary_package_archive_signature(
+        let trusted_keys = crate::signing::load_trusted_public_keys(rootfs.path()).unwrap();
+        verify_binary_package_archive_integrity_with_trusted_keys(
             "repo",
             &repo_cfg,
-            rootfs.path(),
+            &rec,
             &cached.package_path,
             &cached.signature_path,
+            &trusted_keys,
         )
-        .expect("signature verification should succeed");
+        .expect("combined integrity verification should succeed");
+
+        let mut wrong_record = rec.clone();
+        wrong_record.sha512 = crate::hex::encode_lower(Sha512::digest(b"wrong payload"));
+        let error = verify_binary_package_archive_integrity_with_trusted_keys(
+            "repo",
+            &repo_cfg,
+            &wrong_record,
+            &cached.package_path,
+            &cached.signature_path,
+            &trusted_keys,
+        )
+        .expect_err("combined verification must reject a checksum mismatch");
+        assert!(error.to_string().contains("SHA-512 mismatch"));
     }
 
     #[test]
diff --git a/src/signing.rs b/src/signing.rs
index 1f1179e..5926817 100644
--- a/src/signing.rs
+++ b/src/signing.rs
@@ -4,7 +4,7 @@ use anyhow::{Context, Result};
 use inquire::Password;
 use minisign::{PublicKey, SecretKey, SecretKeyBox, SignatureBox};
 use std::fs;
-use std::io::IsTerminal;
+use std::io::{IsTerminal, Read, Seek};
 use std::path::{Path, PathBuf};
 
 const PUBLIC_KEYS_DIR_REL: &str = "usr/share/depot/keys/public";
@@ -164,6 +164,24 @@ pub fn list_trusted_public_keys(rootfs: &Path) -> Result<Vec<PathBuf>> {
     list_public_key_files_in_roots(rootfs, Path::new("/"))
 }
 
+#[derive(Clone)]
+pub(crate) struct TrustedPublicKey {
+    pub(crate) path: PathBuf,
+    pub(crate) key: PublicKey,
+}
+
+pub(crate) fn load_trusted_public_keys(rootfs: &Path) -> Result<Vec<TrustedPublicKey>> {
+    list_trusted_public_keys(rootfs)?
+        .into_iter()
+        .map(|path| {
+            let key = PublicKey::from_file(&path).with_context(|| {
+                format!("Failed to load minisign public key: {}", path.display())
+            })?;
+            Ok(TrustedPublicKey { path, key })
+        })
+        .collect()
+}
+
 fn detached_sig_path(input: &Path) -> PathBuf {
     PathBuf::from(format!("{}.sig", input.display()))
 }
@@ -388,6 +406,70 @@ pub fn verify_zst_file_detached_with_public_key(
     verify_detached_with_key_paths(input, sig_path, &keys)
 }
 
+pub(crate) fn verify_zst_file_detached_with_trusted_keys(
+    input: &Path,
+    sig_path: &Path,
+    trusted_keys: &[TrustedPublicKey],
+) -> Result<PathBuf> {
+    if !input.exists() {
+        anyhow::bail!("File not found: {}", input.display());
+    }
+    if !sig_path.exists() {
+        anyhow::bail!("Detached signature not found: {}", sig_path.display());
+    }
+    if !is_verify_supported_zst_file(input) {
+        anyhow::bail!(
+            "Verification currently only supports .zst and .zst.tmp files: {}",
+            input.display()
+        );
+    }
+
+    let mut file =
+        fs::File::open(input).with_context(|| format!("Failed to open {}", input.display()))?;
+    verify_reader_detached_with_trusted_keys(&mut file, input, sig_path, trusted_keys)
+}
+
+pub(crate) fn verify_reader_detached_with_trusted_keys<R: Read + Seek>(
+    reader: &mut R,
+    input: &Path,
+    sig_path: &Path,
+    trusted_keys: &[TrustedPublicKey],
+) -> Result<PathBuf> {
+    let signature = SignatureBox::from_file(sig_path)
+        .with_context(|| format!("Failed to load detached signature: {}", sig_path.display()))?;
+    let matching_keys = trusted_keys
+        .iter()
+        .filter(|trusted| trusted.key.keynum() == signature.keynum())
+        .collect::<Vec<_>>();
+    if matching_keys.is_empty() {
+        anyhow::bail!(
+            "No trusted minisign public key matches signature key ID {} for {}",
+            crate::hex::encode_lower(signature.keynum()),
+            input.display()
+        );
+    }
+
+    let mut last_failure = None;
+    for trusted in matching_keys {
+        reader
+            .rewind()
+            .with_context(|| format!("Failed to rewind {}", input.display()))?;
+        match minisign::verify(&trusted.key, &signature, &mut *reader, true, false, false) {
+            Ok(()) => return Ok(trusted.path.clone()),
+            Err(err) => last_failure = Some((trusted.path.clone(), err)),
+        }
+    }
+
+    let (key_path, err) = last_failure.expect("at least one matching trusted key was tried");
+    Err(err).with_context(|| {
+        format!(
+            "Detached signature verification failed for {} with trusted key {}",
+            input.display(),
+            key_path.display()
+        )
+    })
+}
+
 /// Sign one or more `.zst` files with detached minisign signatures written to `<file>.sig`.
 pub fn sign_zst_files_detached(rootfs: &Path, inputs: &[PathBuf]) -> Result<Vec<PathBuf>> {
     let signable_inputs = collect_signable_inputs(inputs, true)?;
@@ -584,6 +666,43 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn trusted_key_verification_selects_signature_key_id() -> Result<()> {
+        let rootfs = tempfile::tempdir()?;
+        let file = rootfs.path().join("artifact.tar.zst");
+        fs::write(&file, b"signed payload")?;
+
+        let wrong_pair = KeyPair::generate_unencrypted_keypair()?;
+        let signing_pair = KeyPair::generate_unencrypted_keypair()?;
+        let signature = minisign::sign(
+            Some(&signing_pair.pk),
+            &signing_pair.sk,
+            fs::File::open(&file)?,
+            None,
+            Some("test signature"),
+        )?;
+        let sig_path = detached_sig_path(&file);
+        fs::write(&sig_path, signature.to_bytes())?;
+
+        let wrong_path = rootfs.path().join("wrong.pub");
+        let signing_path = rootfs.path().join("signing.pub");
+        let trusted_keys = vec![
+            TrustedPublicKey {
+                path: wrong_path,
+                key: wrong_pair.pk,
+            },
+            TrustedPublicKey {
+                path: signing_path.clone(),
+                key: signing_pair.pk,
+            },
+        ];
+
+        let verified_path =
+            verify_zst_file_detached_with_trusted_keys(&file, &sig_path, &trusted_keys)?;
+        assert_eq!(verified_path, signing_path);
+        Ok(())
+    }
+
     #[test]
     fn sign_zst_files_detached_signs_multiple_files() -> Result<()> {
         let rootfs = tempfile::tempdir()?;