diff --git a/crates/wasmeld-package/src/dev.rs b/crates/wasmeld-package/src/dev.rs
new file mode 100644
index 0000000..048ee29
--- /dev/null
+++ b/crates/wasmeld-package/src/dev.rs
@@ -0,0 +1,431 @@
+//! Local build, watch, and deployment loop for Component development.
+
+use std::{
+    collections::BTreeSet,
+    env, fs, io,
+    path::{Path, PathBuf},
+    thread,
+    time::Duration,
+};
+
+use reqwest::{
+    StatusCode,
+    blocking::{Client, multipart},
+};
+use serde::Deserialize;
+use sha2::{Digest, Sha256};
+use wasmeld_package::module::{MODULE_MANIFEST_FILE, ModuleManifest};
+
+use crate::{BuildProfile, PackRequest, PackageIdentity, PackedComponent, pack_component};
+
+const DEFAULT_CONSOLE: &str = "http://127.0.0.1:8080";
+const DEFAULT_POLL_MS: u64 = 350;
+
+struct DevOptions {
+    manifest_path: PathBuf,
+    console: String,
+    service_id: Option<String>,
+    locked: bool,
+    release: bool,
+    once: bool,
+    poll_interval: Duration,
+}
+
+#[derive(Debug, Deserialize)]
+struct ServiceList {
+    services: Vec<ServiceIdentity>,
+}
+
+#[derive(Debug, Deserialize)]
+struct ServiceIdentity {
+    id: String,
+    revision: String,
+}
+
+#[derive(Debug, Deserialize)]
+struct Deployment {
+    active_revision: String,
+}
+
+pub(crate) fn run(arguments: Vec<String>) -> Result<(), Box<dyn std::error::Error>> {
+    let options = parse_options(arguments)?;
+    let manifest_path = fs::canonicalize(&options.manifest_path)?;
+    let watch_roots = watch_roots(&manifest_path)?;
+    let client = Client::builder()
+        .user_agent(format!("wasmeld-dev/{}", env!("CARGO_PKG_VERSION")))
+        .timeout(Duration::from_secs(120))
+        .build()?;
+    ensure_console(&client, &options.console)?;
+
+    let temporary_dir = env::temp_dir().join(format!("wasmeld-dev-{}", std::process::id()));
+    fs::create_dir_all(&temporary_dir)?;
+    let output = temporary_dir.join("component.wasmpkg");
+    let mut observed = None;
+
+    println!("watching:");
+    for root in &watch_roots {
+        println!("  {}", root.display());
+    }
+    println!("console: {}", options.console);
+
+    loop {
+        let current = source_fingerprint(&watch_roots)?;
+        if observed.as_ref() == Some(&current) {
+            thread::sleep(options.poll_interval);
+            continue;
+        }
+
+        println!("change detected; building Component");
+        let result = build_and_deploy(&client, &options, &manifest_path, &output);
+        observed = Some(source_fingerprint(&watch_roots)?);
+        match result {
+            Ok(packed) => {
+                println!(
+                    "ready: {}@{} ({})",
+                    packed.manifest.id, packed.manifest.revision, packed.manifest.sha256
+                );
+                if options.once {
+                    return Ok(());
+                }
+            }
+            Err(error) if options.once => return Err(error),
+            Err(error) => {
+                eprintln!("wasmeld dev: {error}");
+                eprintln!("waiting for the next source change; the previous deployment is intact");
+            }
+        }
+    }
+}
+
+fn parse_options(arguments: Vec<String>) -> Result<DevOptions, Box<dyn std::error::Error>> {
+    let mut arguments = arguments.into_iter();
+    let manifest_path = arguments.next().ok_or("dev requires a Cargo.toml path")?;
+    let mut console = env::var("WASMELD_CONSOLE").unwrap_or_else(|_| DEFAULT_CONSOLE.to_owned());
+    let mut service_id = None;
+    let mut locked = false;
+    let mut release = false;
+    let mut once = false;
+    let mut poll_ms = DEFAULT_POLL_MS;
+
+    while let Some(argument) = arguments.next() {
+        match argument.as_str() {
+            "--console" => {
+                console = arguments.next().ok_or("--console requires an HTTP URL")?;
+            }
+            "--id" => {
+                service_id = Some(arguments.next().ok_or("--id requires a service ID")?);
+            }
+            "--locked" => locked = true,
+            "--release" => release = true,
+            "--once" => once = true,
+            "--poll-ms" => {
+                poll_ms = arguments
+                    .next()
+                    .ok_or("--poll-ms requires a number")?
+                    .parse::<u64>()?;
+                if poll_ms < 100 {
+                    return Err("--poll-ms must be at least 100".into());
+                }
+            }
+            _ => return Err(format!("unknown dev argument {argument:?}").into()),
+        }
+    }
+
+    Ok(DevOptions {
+        manifest_path: PathBuf::from(manifest_path),
+        console: console.trim_end_matches('/').to_owned(),
+        service_id,
+        locked,
+        release,
+        once,
+        poll_interval: Duration::from_millis(poll_ms),
+    })
+}
+
+fn build_and_deploy(
+    client: &Client,
+    options: &DevOptions,
+    manifest_path: &Path,
+    output: &Path,
+) -> Result<PackedComponent, Box<dyn std::error::Error>> {
+    let packed = pack_component(PackRequest {
+        manifest_path: manifest_path.to_owned(),
+        output: Some(output.to_owned()),
+        no_build: false,
+        locked: options.locked,
+        profile: if options.release {
+            BuildProfile::Release
+        } else {
+            BuildProfile::Debug
+        },
+        identity: PackageIdentity::Development {
+            id: options.service_id.clone(),
+        },
+    })?;
+    let previous = active_revision(client, &options.console, &packed.manifest.id)?;
+    register(client, &options.console, &packed)?;
+    activate(
+        client,
+        &options.console,
+        &packed.manifest.id,
+        &packed.manifest.revision,
+    )?;
+
+    if let Some(previous) = previous
+        && previous != packed.manifest.revision
+        && is_matching_dev_revision(&previous, &packed.manifest.revision)
+        && let Err(error) = unregister(client, &options.console, &packed.manifest.id, &previous)
+    {
+        eprintln!(
+            "wasmeld dev: deployed successfully but could not unregister {}@{}: {error}",
+            packed.manifest.id, previous
+        );
+    }
+    Ok(packed)
+}
+
+fn ensure_console(client: &Client, console: &str) -> Result<(), Box<dyn std::error::Error>> {
+    let response = client.get(format!("{console}/healthz")).send()?;
+    if response.status().is_success() {
+        Ok(())
+    } else {
+        Err(http_error("Console health check", response))
+    }
+}
+
+fn active_revision(
+    client: &Client,
+    console: &str,
+    service_id: &str,
+) -> Result<Option<String>, Box<dyn std::error::Error>> {
+    let response = client
+        .get(format!("{console}/api/v1/deployments/{service_id}"))
+        .send()?;
+    match response.status() {
+        status if status.is_success() => Ok(Some(response.json::<Deployment>()?.active_revision)),
+        StatusCode::NOT_FOUND => Ok(None),
+        _ => Err(http_error("deployment lookup", response)),
+    }
+}
+
+fn register(
+    client: &Client,
+    console: &str,
+    packed: &PackedComponent,
+) -> Result<(), Box<dyn std::error::Error>> {
+    let package = fs::read(&packed.output)?;
+    let part = multipart::Part::bytes(package)
+        .file_name("component.wasmpkg")
+        .mime_str("application/vnd.wasmeld.package")?;
+    let response = client
+        .post(format!("{console}/api/v1/services"))
+        .multipart(multipart::Form::new().part("package", part))
+        .send()?;
+    if response.status().is_success() {
+        return Ok(());
+    }
+    if response.status() == StatusCode::CONFLICT
+        && service_exists(
+            client,
+            console,
+            &packed.manifest.id,
+            &packed.manifest.revision,
+        )?
+    {
+        return Ok(());
+    }
+    Err(http_error("Component registration", response))
+}
+
+fn service_exists(
+    client: &Client,
+    console: &str,
+    service_id: &str,
+    revision: &str,
+) -> Result<bool, Box<dyn std::error::Error>> {
+    let response = client.get(format!("{console}/api/v1/services")).send()?;
+    if !response.status().is_success() {
+        return Err(http_error("service lookup", response));
+    }
+    Ok(response
+        .json::<ServiceList>()?
+        .services
+        .iter()
+        .any(|service| service.id == service_id && service.revision == revision))
+}
+
+fn activate(
+    client: &Client,
+    console: &str,
+    service_id: &str,
+    revision: &str,
+) -> Result<(), Box<dyn std::error::Error>> {
+    let response = client
+        .post(format!(
+            "{console}/api/v1/deployments/{service_id}/activate"
+        ))
+        .json(&serde_json::json!({ "revision": revision }))
+        .send()?;
+    if response.status().is_success() {
+        Ok(())
+    } else {
+        Err(http_error("development deployment", response))
+    }
+}
+
+fn unregister(
+    client: &Client,
+    console: &str,
+    service_id: &str,
+    revision: &str,
+) -> Result<(), Box<dyn std::error::Error>> {
+    let response = client
+        .delete(format!("{console}/api/v1/services/{service_id}/{revision}"))
+        .send()?;
+    if response.status().is_success() || response.status() == StatusCode::NOT_FOUND {
+        Ok(())
+    } else {
+        Err(http_error("old development revision cleanup", response))
+    }
+}
+
+fn http_error(action: &str, response: reqwest::blocking::Response) -> Box<dyn std::error::Error> {
+    let status = response.status();
+    let body = response
+        .text()
+        .unwrap_or_else(|error| format!("failed to read response: {error}"));
+    format!("{action} returned HTTP {status}: {body}").into()
+}
+
+fn is_matching_dev_revision(previous: &str, current: &str) -> bool {
+    let Some((previous_base, previous_hash)) = previous.rsplit_once("-dev.h") else {
+        return false;
+    };
+    let Some((current_base, current_hash)) = current.rsplit_once("-dev.h") else {
+        return false;
+    };
+    previous_base == current_base && valid_dev_hash(previous_hash) && valid_dev_hash(current_hash)
+}
+
+fn valid_dev_hash(value: &str) -> bool {
+    value.len() == 12 && value.bytes().all(|byte| byte.is_ascii_hexdigit())
+}
+
+fn watch_roots(manifest_path: &Path) -> Result<Vec<PathBuf>, Box<dyn std::error::Error>> {
+    let component_root = manifest_path
+        .parent()
+        .ok_or("Cargo manifest must have a parent directory")?
+        .to_owned();
+    let mut roots = BTreeSet::from([component_root.clone()]);
+    let module_path = component_root.join(MODULE_MANIFEST_FILE);
+    if module_path.is_file() {
+        let module = ModuleManifest::read(&module_path)?;
+        for replacement in module.replacements.values() {
+            let path = component_root.join(&replacement.path);
+            if path.exists() {
+                roots.insert(fs::canonicalize(path)?);
+            }
+        }
+    }
+    Ok(roots.into_iter().collect())
+}
+
+fn source_fingerprint(roots: &[PathBuf]) -> Result<Vec<u8>, Box<dyn std::error::Error>> {
+    let mut files = BTreeSet::new();
+    for root in roots {
+        collect_source_files(root, &mut files)?;
+    }
+    let mut digest = Sha256::new();
+    for path in files {
+        digest.update(path.to_string_lossy().as_bytes());
+        match fs::read(&path) {
+            Ok(bytes) => digest.update(bytes),
+            Err(error) if error.kind() == io::ErrorKind::NotFound => {}
+            Err(error) => return Err(error.into()),
+        }
+    }
+    Ok(digest.finalize().to_vec())
+}
+
+fn collect_source_files(
+    path: &Path,
+    files: &mut BTreeSet<PathBuf>,
+) -> Result<(), Box<dyn std::error::Error>> {
+    if path.is_dir() {
+        if ignored_directory(path) {
+            return Ok(());
+        }
+        for entry in fs::read_dir(path)? {
+            collect_source_files(&entry?.path(), files)?;
+        }
+    } else if is_source_file(path) {
+        files.insert(path.to_owned());
+    }
+    Ok(())
+}
+
+fn ignored_directory(path: &Path) -> bool {
+    let name = path.file_name().and_then(|name| name.to_str());
+    if matches!(
+        name,
+        Some(".git" | ".wasmeld" | "deps" | "dist" | "node_modules" | "target")
+    ) {
+        return name != Some("deps")
+            || path
+                .parent()
+                .and_then(Path::file_name)
+                .and_then(|name| name.to_str())
+                == Some("wit");
+    }
+    false
+}
+
+fn is_source_file(path: &Path) -> bool {
+    matches!(
+        path.extension().and_then(|extension| extension.to_str()),
+        Some("rs" | "wit")
+    ) || matches!(
+        path.file_name().and_then(|name| name.to_str()),
+        Some("Cargo.lock" | "Cargo.toml" | "config.toml" | "wasmeld.toml" | "wit.lock")
+    )
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn recognizes_only_matching_hash_development_revisions() {
+        assert!(is_matching_dev_revision(
+            "0.1.0-dev.h0123456789ab",
+            "0.1.0-dev.habcdef012345"
+        ));
+        assert!(!is_matching_dev_revision(
+            "0.2.0-dev.h0123456789ab",
+            "0.1.0-dev.habcdef012345"
+        ));
+        assert!(!is_matching_dev_revision(
+            "0.1.0",
+            "0.1.0-dev.habcdef012345"
+        ));
+    }
+
+    #[test]
+    fn fingerprints_sources_but_ignores_materialized_wit_dependencies() {
+        let root = tempfile::tempdir().unwrap();
+        let source = root.path().join("src/lib.rs");
+        let generated = root.path().join("wit/deps/example/package.wit");
+        fs::create_dir_all(source.parent().unwrap()).unwrap();
+        fs::create_dir_all(generated.parent().unwrap()).unwrap();
+        fs::write(&source, "pub fn first() {}").unwrap();
+        fs::write(&generated, "package generated:dependency@1.0.0;").unwrap();
+        let roots = vec![root.path().to_owned()];
+        let initial = source_fingerprint(&roots).unwrap();
+
+        fs::write(&generated, "package generated:dependency@2.0.0;").unwrap();
+        assert_eq!(source_fingerprint(&roots).unwrap(), initial);
+
+        fs::write(&source, "pub fn second() {}").unwrap();
+        assert_ne!(source_fingerprint(&roots).unwrap(), initial);
+    }
+}
diff --git a/crates/wasmeld-package/src/main.rs b/crates/wasmeld-package/src/main.rs
index 6c2cedf..b60d2e9 100644
--- a/crates/wasmeld-package/src/main.rs
+++ b/crates/wasmeld-package/src/main.rs
@@ -1,5 +1,7 @@
 //! Command-line entry point for Component packaging and WIT dependency workflows.
 
+mod dev;
+
 use std::{
     env, fs,
     path::{Path, PathBuf},
@@ -7,6 +9,7 @@ use std::{
 };
 
 use serde::Deserialize;
+use sha2::{Digest, Sha256};
 use wasmeld_package::{
     PackageManifest,
     module::{MODULE_MANIFEST_FILE, ModuleManifest, find_module_manifest, sync_dependencies},
@@ -16,6 +19,41 @@ use wasmeld_package::{
 
 const TARGET: &str = "wasm32-wasip2";
 
+#[derive(Clone, Copy)]
+pub(crate) enum BuildProfile {
+    Debug,
+    Release,
+}
+
+impl BuildProfile {
+    fn directory(self) -> &'static str {
+        match self {
+            Self::Debug => "debug",
+            Self::Release => "release",
+        }
+    }
+}
+
+pub(crate) enum PackageIdentity {
+    Cargo,
+    Development { id: Option<String> },
+}
+
+pub(crate) struct PackRequest {
+    pub manifest_path: PathBuf,
+    pub output: Option<PathBuf>,
+    pub no_build: bool,
+    pub locked: bool,
+    pub profile: BuildProfile,
+    pub identity: PackageIdentity,
+}
+
+pub(crate) struct PackedComponent {
+    pub manifest: PackageManifest,
+    pub output: PathBuf,
+    pub artifact: PathBuf,
+}
+
 #[derive(Debug, Deserialize)]
 struct CargoMetadata {
     packages: Vec<CargoPackage>,
@@ -51,6 +89,7 @@ fn run() -> Result<(), Box<dyn std::error::Error>> {
     let mut arguments = env::args().skip(1);
     match arguments.next().as_deref() {
         Some("pack") => run_pack(arguments.collect()),
+        Some("dev") => dev::run(arguments.collect()),
         Some("wit") => run_wit(arguments.collect()),
         _ => Err(usage().into()),
     }
@@ -78,69 +117,102 @@ fn run_pack(arguments: Vec<String>) -> Result<(), Box<dyn std::error::Error>> {
         }
     }
 
-    let manifest_path = fs::canonicalize(manifest_path)?;
-    sync_component_dependencies(&manifest_path, locked)?;
+    let packed = pack_component(PackRequest {
+        manifest_path: PathBuf::from(manifest_path),
+        output,
+        no_build,
+        locked,
+        profile: BuildProfile::Release,
+        identity: PackageIdentity::Cargo,
+    })?;
+
+    println!(
+        "packed {}@{} -> {}",
+        packed.manifest.id,
+        packed.manifest.revision,
+        packed.output.display()
+    );
+    println!("component: {}", packed.artifact.display());
+    println!("sha256: {}", packed.manifest.sha256);
+    Ok(())
+}
+
+pub(crate) fn pack_component(
+    request: PackRequest,
+) -> Result<PackedComponent, Box<dyn std::error::Error>> {
+    let manifest_path = fs::canonicalize(request.manifest_path)?;
+    sync_component_dependencies(&manifest_path, request.locked)?;
     let metadata = cargo_metadata(&manifest_path)?;
     let package = metadata
         .packages
         .iter()
         .find(|package| package.manifest_path == manifest_path)
         .ok_or("Cargo metadata did not contain the requested package")?;
-    let id = package
+    let cargo_id = package
         .metadata
         .get("wasmeld")
         .and_then(|metadata| metadata.get("id"))
         .and_then(serde_json::Value::as_str)
-        .ok_or("[package.metadata.wasmeld].id is required")?;
+        .ok_or("[package.metadata.wasmeld].id is required")?
+        .to_owned();
     let world = package
         .metadata
         .get("wasmeld")
         .and_then(|metadata| metadata.get("world"))
         .and_then(serde_json::Value::as_str)
-        .ok_or("[package.metadata.wasmeld].world is required")?;
-    PackageManifest::new(id, &package.version, world, b"identity-validation").validate()?;
+        .ok_or("[package.metadata.wasmeld].world is required")?
+        .to_owned();
+    let cargo_revision = package.version.clone();
     let target = package
         .targets
         .iter()
         .find(|target| target.crate_types.iter().any(|kind| kind == "cdylib"))
-        .ok_or("component package must expose a cdylib target")?;
+        .ok_or("component package must expose a cdylib target")?
+        .name
+        .clone();
 
-    if !no_build {
-        build_component(&manifest_path)?;
+    if !request.no_build {
+        build_component(&manifest_path, request.profile)?;
     }
 
     let artifact = metadata
         .target_directory
         .join(TARGET)
-        .join("release")
-        .join(format!("{}.wasm", target.name.replace('-', "_")));
+        .join(request.profile.directory())
+        .join(format!("{}.wasm", target.replace('-', "_")));
     let component = fs::read(&artifact).map_err(|error| {
         format!(
             "failed to read built component {}: {error}",
             artifact.display()
         )
     })?;
-    let output = output.unwrap_or_else(|| {
+    let (id, revision) = match request.identity {
+        PackageIdentity::Cargo => (cargo_id, cargo_revision),
+        PackageIdentity::Development { id } => {
+            let digest = format!("{:x}", Sha256::digest(&component));
+            (
+                id.unwrap_or_else(|| format!("{cargo_id}-dev")),
+                format!("{cargo_revision}-dev.h{}", &digest[..12]),
+            )
+        }
+    };
+    PackageManifest::new(&id, &revision, &world, b"identity-validation").validate()?;
+    let output = request.output.unwrap_or_else(|| {
         metadata
             .workspace_root
             .join("dist")
-            .join(format!("{id}-{}.wasmpkg", package.version))
+            .join(format!("{id}-{revision}.wasmpkg"))
     });
     if let Some(parent) = output.parent() {
         fs::create_dir_all(parent)?;
     }
     let file = fs::File::create(&output)?;
-    let manifest = write_package(file, id, &package.version, world, &component)?;
-
-    println!(
-        "packed {}@{} -> {}",
-        manifest.id,
-        manifest.revision,
-        output.display()
-    );
-    println!("component: {}", artifact.display());
-    println!("sha256: {}", manifest.sha256);
-    Ok(())
+    let manifest = write_package(file, id, revision, world, &component)?;
+    Ok(PackedComponent {
+        manifest,
+        output,
+        artifact,
+    })
 }
 
 fn run_wit(arguments: Vec<String>) -> Result<(), Box<dyn std::error::Error>> {
@@ -426,14 +498,21 @@ fn cargo_metadata(manifest_path: &Path) -> Result<CargoMetadata, Box<dyn std::er
     Ok(serde_json::from_slice(&output.stdout)?)
 }
 
-fn build_component(manifest_path: &Path) -> Result<(), Box<dyn std::error::Error>> {
+fn build_component(
+    manifest_path: &Path,
+    profile: BuildProfile,
+) -> Result<(), Box<dyn std::error::Error>> {
     let toolchain = env::var("WASMELD_COMPONENT_TOOLCHAIN").unwrap_or_else(|_| "1.90.0".to_owned());
-    let status = Command::new("rustup")
+    let mut command = Command::new("rustup");
+    command
         .args(["run", &toolchain, "cargo", "build"])
         .arg("--manifest-path")
         .arg(manifest_path)
-        .args(["--target", TARGET, "--release"])
-        .status()?;
+        .args(["--target", TARGET]);
+    if matches!(profile, BuildProfile::Release) {
+        command.arg("--release");
+    }
+    let status = command.status()?;
     if !status.success() {
         return Err(format!("component build failed with status {status}").into());
     }
@@ -443,6 +522,7 @@ fn build_component(manifest_path: &Path) -> Result<(), Box<dyn std::error::Error
 fn usage() -> String {
     "usage:
   wasmeld pack <Cargo.toml> [--output <file.wasmpkg>] [--no-build] [--locked]
+  wasmeld dev <Cargo.toml> [--console <url>] [--id <service-id>] [--locked] [--release] [--once] [--poll-ms <milliseconds>]
   wasmeld wit fetch [--manifest <wasmeld.toml>] [--locked]
   wasmeld wit tidy [--manifest <wasmeld.toml>] [--locked]
   wasmeld wit graph [--manifest <wasmeld.toml>]