diff --git a/decnet/cli.py b/decnet/cli.py
index 3bcf73e..d3dc760 100644
--- a/decnet/cli.py
+++ b/decnet/cli.py
@@ -8,7 +8,7 @@ Usage:
   decnet services
 """
 
-import random
+import signal
 from typing import Optional
 
 import typer
@@ -28,7 +28,8 @@ from decnet.config import (
     DecnetConfig,
     random_hostname,
 )
-from decnet.distros import all_distros, get_distro, random_distro
+from decnet.distros import all_distros, get_distro
+from decnet.fleet import all_service_names, build_deckies, build_deckies_from_ini
 from decnet.ini_loader import IniConfig, load_ini
 from decnet.network import detect_interface, detect_subnet, allocate_ips, get_host_ip
 from decnet.services.registry import all_services
@@ -40,171 +41,31 @@ app = typer.Typer(
 )
 console = Console()
 
-def _all_service_names() -> list[str]:
-    """Return all registered service names from the live plugin registry."""
-    return sorted(all_services().keys())
 
+def _kill_api() -> None:
+    """Find and kill any running DECNET API (uvicorn) or mutator processes."""
+    import psutil
+    import os
 
-def _resolve_distros(
-    distros_explicit: list[str] | None,
-    randomize_distros: bool,
-    n: int,
-    archetype: Archetype | None = None,
-) -> list[str]:
-    """Return a list of n distro slugs based on CLI flags or archetype preference."""
-    if distros_explicit:
-        return [distros_explicit[i % len(distros_explicit)] for i in range(n)]
-    if randomize_distros:
-        return [random_distro().slug for _ in range(n)]
-    if archetype:
-        pool = archetype.preferred_distros
-        return [pool[i % len(pool)] for i in range(n)]
-    # Default: cycle through all distros to maximize heterogeneity
-    slugs = list(all_distros().keys())
-    return [slugs[i % len(slugs)] for i in range(n)]
-
-
-def _build_deckies(
-    n: int,
-    ips: list[str],
-    services_explicit: list[str] | None,
-    randomize_services: bool,
-    distros_explicit: list[str] | None = None,
-    randomize_distros: bool = False,
-    archetype: Archetype | None = None,
-) -> list[DeckyConfig]:
-    deckies = []
-    used_combos: set[frozenset] = set()
-    distro_slugs = _resolve_distros(distros_explicit, randomize_distros, n, archetype)
-
-    for i, ip in enumerate(ips):
-        name = f"decky-{i + 1:02d}"
-        distro = get_distro(distro_slugs[i])
-        hostname = random_hostname(distro.slug)
-
-        if services_explicit:
-            svc_list = services_explicit
-        elif archetype:
-            svc_list = list(archetype.services)
-        elif randomize_services:
-            svc_pool = _all_service_names()
-            attempts = 0
-            while True:
-                count = random.randint(1, min(3, len(svc_pool)))  # nosec B311
-                chosen = frozenset(random.sample(svc_pool, count))  # nosec B311
-                attempts += 1
-                if chosen not in used_combos or attempts > 20:
-                    break
-            svc_list = list(chosen)
-            used_combos.add(chosen)
-        else:
-            typer.echo("Error: provide --services, --archetype, or --randomize-services.", err=True)
-            raise typer.Exit(1)
-
-        deckies.append(
-            DeckyConfig(
-                name=name,
-                ip=ip,
-                services=svc_list,
-                distro=distro.slug,
-                base_image=distro.image,
-                build_base=distro.build_base,
-                hostname=hostname,
-                archetype=archetype.slug if archetype else None,
-                nmap_os=archetype.nmap_os if archetype else "linux",
-            )
-        )
-    return deckies
-
-
-def _build_deckies_from_ini(
-    ini: IniConfig,
-    subnet_cidr: str,
-    gateway: str,
-    host_ip: str,
-    randomize: bool,
-    cli_mutate_interval: int | None = None,
-) -> list[DeckyConfig]:
-    """Build DeckyConfig list from an IniConfig, auto-allocating missing IPs."""
-    from ipaddress import IPv4Address, IPv4Network
-    import time
-    now = time.time()
-
-    explicit_ips: set[IPv4Address] = {
-        IPv4Address(s.ip) for s in ini.deckies if s.ip
-    }
-
-    net = IPv4Network(subnet_cidr, strict=False)
-    reserved = {
-        net.network_address,
-        net.broadcast_address,
-        IPv4Address(gateway),
-        IPv4Address(host_ip),
-    } | explicit_ips
-
-    auto_pool = (str(addr) for addr in net.hosts() if addr not in reserved)
-
-    deckies: list[DeckyConfig] = []
-    for spec in ini.deckies:
-        # Resolve archetype (if any) — explicit services/distro override it
-        arch: Archetype | None = None
-        if spec.archetype:
-            arch = get_archetype(spec.archetype)
-
-        # Distro: archetype preferred list → random → global cycle
-        distro_pool = arch.preferred_distros if arch else list(all_distros().keys())
-        distro = get_distro(distro_pool[len(deckies) % len(distro_pool)])
-        hostname = random_hostname(distro.slug)
-
-        ip = spec.ip or next(auto_pool, None)
-        if ip is None:
-            raise ValueError(f"Not enough free IPs in {subnet_cidr} while assigning IP for '{spec.name}'.")
-
-        if spec.services:
-            known = set(_all_service_names())
-            unknown = [s for s in spec.services if s not in known]
-            if unknown:
-                raise ValueError(
-                    f"Unknown service(s) in [{spec.name}]: {unknown}. "
-                    f"Available: {_all_service_names()}"
-                )
-            svc_list = spec.services
-        elif arch:
-            svc_list = list(arch.services)
-        elif randomize:
-            svc_pool = _all_service_names()
-            count = random.randint(1, min(3, len(svc_pool)))  # nosec B311
-            svc_list = random.sample(svc_pool, count)  # nosec B311
-        else:
-            raise ValueError(
-                f"Decky '[{spec.name}]' has no services= in config. "
-                "Add services=, archetype=, or use --randomize-services."
-            )
-
-        # nmap_os priority: explicit INI key > archetype default > "linux"
-        resolved_nmap_os = spec.nmap_os or (arch.nmap_os if arch else "linux")
-        
-        # mutation interval priority: CLI > per-decky INI > global INI
-        decky_mutate_interval = cli_mutate_interval
-        if decky_mutate_interval is None:
-            decky_mutate_interval = spec.mutate_interval if spec.mutate_interval is not None else ini.mutate_interval
-
-        deckies.append(DeckyConfig(
-            name=spec.name,
-            ip=ip,
-            services=svc_list,
-            distro=distro.slug,
-            base_image=distro.image,
-            build_base=distro.build_base,
-            hostname=hostname,
-            archetype=arch.slug if arch else None,
-            service_config=spec.service_config,
-            nmap_os=resolved_nmap_os,
-            mutate_interval=decky_mutate_interval,
-            last_mutated=now,
-        ))
-    return deckies
+    _killed: bool = False
+    for _proc in psutil.process_iter(['pid', 'name', 'cmdline']):
+        try:
+            _cmd = _proc.info['cmdline']
+            if not _cmd:
+                continue
+            if "uvicorn" in _cmd and "decnet.web.api:app" in _cmd:
+                console.print(f"[yellow]Stopping DECNET API (PID {_proc.info['pid']})...[/]")
+                os.kill(_proc.info['pid'], signal.SIGTERM)
+                _killed = True
+            elif "decnet.cli" in _cmd and "mutate" in _cmd and "--watch" in _cmd:
+                console.print(f"[yellow]Stopping DECNET Mutator Watcher (PID {_proc.info['pid']})...[/]")
+                os.kill(_proc.info['pid'], signal.SIGTERM)
+                _killed = True
+        except (psutil.NoSuchProcess, psutil.AccessDenied):
+            continue
 
+    if _killed:
+        console.print("[green]Background processes stopped.[/]")
 
 
 @app.command()
@@ -270,7 +131,6 @@ def deploy(
             console.print(f"[red]{e}[/]")
             raise typer.Exit(1)
 
-        # CLI flags override INI values when explicitly provided
         iface = interface or ini.interface or detect_interface()
         subnet_cidr = subnet or ini.subnet
         effective_gateway = ini.gateway
@@ -284,7 +144,6 @@ def deploy(
                       f"[dim]Subnet:[/] {subnet_cidr}  [dim]Gateway:[/] {effective_gateway}  "
                       f"[dim]Host IP:[/] {host_ip}")
 
-        # Register bring-your-own services from INI before validation
         if ini.custom_services:
             from decnet.custom_service import CustomService
             from decnet.services.registry import register_custom_service
@@ -300,7 +159,7 @@ def deploy(
 
         effective_log_file = log_file
         try:
-            decky_configs = _build_deckies_from_ini(
+            decky_configs = build_deckies_from_ini(
                 ini, subnet_cidr, effective_gateway, host_ip, randomize_services, cli_mutate_interval=mutate_interval
             )
         except ValueError as e:
@@ -316,13 +175,12 @@ def deploy(
 
         services_list = [s.strip() for s in services.split(",")] if services else None
         if services_list:
-            known = set(_all_service_names())
+            known = set(all_service_names())
             unknown = [s for s in services_list if s not in known]
             if unknown:
-                console.print(f"[red]Unknown service(s): {unknown}. Available: {_all_service_names()}[/]")
+                console.print(f"[red]Unknown service(s): {unknown}. Available: {all_service_names()}[/]")
                 raise typer.Exit(1)
 
-        # Resolve archetype if provided
         arch: Archetype | None = None
         if archetype_name:
             try:
@@ -356,14 +214,13 @@ def deploy(
                 raise typer.Exit(1)
 
         ips = allocate_ips(subnet_cidr, effective_gateway, host_ip, deckies, ip_start)
-        decky_configs = _build_deckies(
+        decky_configs = build_deckies(
             deckies, ips, services_list, randomize_services,
             distros_explicit=distros_list, randomize_distros=randomize_distros,
             archetype=arch, mutate_interval=mutate_interval,
         )
         effective_log_file = log_file
 
-    # Handle automatic log file for API
     if api and not effective_log_file:
         effective_log_file = os.path.join(os.getcwd(), "decnet.log")
         console.print(f"[cyan]API mode enabled: defaulting log-file to {effective_log_file}[/]")
@@ -379,9 +236,9 @@ def deploy(
         mutate_interval=mutate_interval,
     )
 
-    from decnet.deployer import deploy as _deploy
+    from decnet.engine import deploy as _deploy
     _deploy(config, dry_run=dry_run, no_cache=no_cache, parallel=parallel)
-    
+
     if mutate_interval is not None and not dry_run:
         import subprocess  # nosec B404
         import sys
@@ -396,8 +253,6 @@ def deploy(
         except (FileNotFoundError, subprocess.SubprocessError):
             console.print("[red]Failed to start mutator watcher.[/]")
 
-    # Start the log collector as a background process unless --api is handling it.
-    # The collector streams Docker logs → log_file (RFC 5424) + log_file.json.
     if effective_log_file and not dry_run and not api:
         import subprocess  # noqa: F811  # nosec B404
         import sys
@@ -436,7 +291,7 @@ def collect(
 ) -> None:
     """Stream Docker logs from all running decky service containers to a log file."""
     import asyncio
-    from decnet.web.collector import log_collector_worker
+    from decnet.collector import log_collector_worker
     console.print(f"[bold cyan]Collector starting[/] → {log_file}")
     asyncio.run(log_collector_worker(log_file))
 
@@ -465,7 +320,7 @@ def mutate(
 @app.command()
 def status() -> None:
     """Show running deckies and their status."""
-    from decnet.deployer import status as _status
+    from decnet.engine import status as _status
     _status()
 
 
@@ -479,9 +334,12 @@ def teardown(
         console.print("[red]Specify --all or --id <name>.[/]")
         raise typer.Exit(1)
 
-    from decnet.deployer import teardown as _teardown
+    from decnet.engine import teardown as _teardown
     _teardown(decky_id=id_)
 
+    if all_:
+        _kill_api()
+
 
 @app.command(name="services")
 def list_services() -> None:
@@ -591,7 +449,6 @@ def serve_web(
     import socketserver
     from pathlib import Path
 
-    # Assuming decnet_web/dist is relative to the project root
     dist_dir = Path(__file__).parent.parent / "decnet_web" / "dist"
 
     if not dist_dir.exists():
@@ -600,10 +457,8 @@ def serve_web(
 
     class SPAHTTPRequestHandler(http.server.SimpleHTTPRequestHandler):
         def do_GET(self):
-            # Try to serve the requested file
             path = self.translate_path(self.path)
             if not Path(path).exists() or Path(path).is_dir():
-                # If not found or is a directory, serve index.html (for React Router)
                 self.path = "/index.html"
             return super().do_GET()
 
diff --git a/decnet/collector/__init__.py b/decnet/collector/__init__.py
new file mode 100644
index 0000000..5dcaf34
--- /dev/null
+++ b/decnet/collector/__init__.py
@@ -0,0 +1,13 @@
+from decnet.collector.worker import (
+    is_service_container,
+    is_service_event,
+    log_collector_worker,
+    parse_rfc5424,
+)
+
+__all__ = [
+    "is_service_container",
+    "is_service_event",
+    "log_collector_worker",
+    "parse_rfc5424",
+]
diff --git a/decnet/web/collector.py b/decnet/collector/worker.py
similarity index 98%
rename from decnet/web/collector.py
rename to decnet/collector/worker.py
index 1eb5119..69e2c6b 100644
--- a/decnet/web/collector.py
+++ b/decnet/collector/worker.py
@@ -14,7 +14,7 @@ from datetime import datetime
 from pathlib import Path
 from typing import Any, Optional
 
-logger = logging.getLogger("decnet.web.collector")
+logger = logging.getLogger("decnet.collector")
 
 # ─── RFC 5424 parser ──────────────────────────────────────────────────────────
 
@@ -175,12 +175,10 @@ async def log_collector_worker(log_file: str) -> None:
     try:
         client = docker.from_env()
 
-        # Collect from already-running containers
         for container in client.containers.list():
             if is_service_container(container):
                 _spawn(container.id, container.name.lstrip("/"))
 
-        # Watch for new containers starting
         def _watch_events() -> None:
             for event in client.events(
                 decode=True,
diff --git a/decnet/engine/__init__.py b/decnet/engine/__init__.py
new file mode 100644
index 0000000..f2edfb1
--- /dev/null
+++ b/decnet/engine/__init__.py
@@ -0,0 +1,15 @@
+from decnet.engine.deployer import (
+    COMPOSE_FILE,
+    _compose_with_retry,
+    deploy,
+    status,
+    teardown,
+)
+
+__all__ = [
+    "COMPOSE_FILE",
+    "_compose_with_retry",
+    "deploy",
+    "status",
+    "teardown",
+]
diff --git a/decnet/deployer.py b/decnet/engine/deployer.py
similarity index 82%
rename from decnet/deployer.py
rename to decnet/engine/deployer.py
index 92e2fb6..3f03c63 100644
--- a/decnet/deployer.py
+++ b/decnet/engine/deployer.py
@@ -28,7 +28,7 @@ from decnet.network import (
 
 console = Console()
 COMPOSE_FILE = Path("decnet-compose.yml")
-_CANONICAL_LOGGING = Path(__file__).parent.parent / "templates" / "decnet_logging.py"
+_CANONICAL_LOGGING = Path(__file__).parent.parent.parent / "templates" / "decnet_logging.py"
 
 
 def _sync_logging_helper(config: DecnetConfig) -> None:
@@ -108,7 +108,6 @@ def _compose_with_retry(
 def deploy(config: DecnetConfig, dry_run: bool = False, no_cache: bool = False, parallel: bool = False) -> None:
     client = docker.from_env()
 
-    # --- Network setup ---
     ip_list = [d.ip for d in config.deckies]
     decky_range = ips_to_range(ip_list)
     host_ip = get_host_ip(config.interface)
@@ -135,10 +134,8 @@ def deploy(config: DecnetConfig, dry_run: bool = False, no_cache: bool = False,
             )
             setup_host_macvlan(config.interface, host_ip, decky_range)
 
-    # --- Sync shared logging helper into each template build context ---
     _sync_logging_helper(config)
 
-    # --- Compose generation ---
     compose_path = write_compose(config, COMPOSE_FILE)
     console.print(f"[bold cyan]Compose file written[/] → {compose_path}")
 
@@ -146,13 +143,8 @@ def deploy(config: DecnetConfig, dry_run: bool = False, no_cache: bool = False,
         console.print("[yellow]Dry run — no containers started.[/]")
         return
 
-    # --- Save state before bring-up ---
     save_state(config, compose_path)
 
-    # --- Bring up ---
-    # With --parallel: force BuildKit, run build explicitly (so all images are
-    # built concurrently before any container starts), then up without --build.
-    # Without --parallel: keep the original up --build path.
     build_env = {"DOCKER_BUILDKIT": "1"} if parallel else {}
 
     console.print("[bold cyan]Building images and starting deckies...[/]")
@@ -169,37 +161,9 @@ def deploy(config: DecnetConfig, dry_run: bool = False, no_cache: bool = False,
             _compose_with_retry("build", "--no-cache", compose_file=compose_path)
         _compose_with_retry("up", "--build", "-d", compose_file=compose_path)
 
-    # --- Status summary ---
     _print_status(config)
 
 
-def _kill_api() -> None:
-    """Find and kill any running DECNET API (uvicorn) or mutator processes."""
-    import psutil
-    import signal
-    import os
-
-    _killed: bool = False
-    for _proc in psutil.process_iter(['pid', 'name', 'cmdline']):
-        try:
-            _cmd = _proc.info['cmdline']
-            if not _cmd:
-                continue
-            if "uvicorn" in _cmd and "decnet.web.api:app" in _cmd:
-                console.print(f"[yellow]Stopping DECNET API (PID {_proc.info['pid']})...[/]")
-                os.kill(_proc.info['pid'], signal.SIGTERM)
-                _killed = True
-            elif "decnet.cli" in _cmd and "mutate" in _cmd and "--watch" in _cmd:
-                console.print(f"[yellow]Stopping DECNET Mutator Watcher (PID {_proc.info['pid']})...[/]")
-                os.kill(_proc.info['pid'], signal.SIGTERM)
-                _killed = True
-        except (psutil.NoSuchProcess, psutil.AccessDenied):
-            continue
-    
-    if _killed:
-        console.print("[green]Background processes stopped.[/]")
-
-
 def teardown(decky_id: str | None = None) -> None:
     state = load_state()
     if state is None:
@@ -210,7 +174,6 @@ def teardown(decky_id: str | None = None) -> None:
     client = docker.from_env()
 
     if decky_id:
-        # Bring down only the services matching this decky
         svc_names = [f"{decky_id}-{svc}" for svc in [d.services for d in config.deckies if d.name == decky_id]]
         if not svc_names:
             console.print(f"[red]Decky '{decky_id}' not found in current deployment.[/]")
@@ -228,10 +191,7 @@ def teardown(decky_id: str | None = None) -> None:
             teardown_host_macvlan(decky_range)
         remove_macvlan_network(client)
         clear_state()
-        
-        # Kill API when doing full teardown
-        _kill_api()
-        
+
         net_driver = "IPvlan" if config.ipvlan else "MACVLAN"
         console.print(f"[green]All deckies torn down. {net_driver} network removed.[/]")
 
diff --git a/decnet/fleet.py b/decnet/fleet.py
new file mode 100644
index 0000000..cd9984e
--- /dev/null
+++ b/decnet/fleet.py
@@ -0,0 +1,179 @@
+"""
+Fleet builder — shared logic for constructing DeckyConfig lists.
+
+Used by both the CLI and the web API router to build deckies from
+flags or INI config. Lives here (not in cli.py) so that the web layer
+and the mutation engine can import it without depending on the CLI.
+"""
+
+import random
+from typing import Optional
+
+from decnet.archetypes import Archetype, get_archetype
+from decnet.config import DeckyConfig, random_hostname
+from decnet.distros import all_distros, get_distro, random_distro
+from decnet.ini_loader import IniConfig
+from decnet.services.registry import all_services
+
+
+def all_service_names() -> list[str]:
+    """Return all registered service names from the live plugin registry."""
+    return sorted(all_services().keys())
+
+
+def resolve_distros(
+    distros_explicit: list[str] | None,
+    randomize_distros: bool,
+    n: int,
+    archetype: Archetype | None = None,
+) -> list[str]:
+    """Return a list of n distro slugs based on flags or archetype preference."""
+    if distros_explicit:
+        return [distros_explicit[i % len(distros_explicit)] for i in range(n)]
+    if randomize_distros:
+        return [random_distro().slug for _ in range(n)]
+    if archetype:
+        pool = archetype.preferred_distros
+        return [pool[i % len(pool)] for i in range(n)]
+    slugs = list(all_distros().keys())
+    return [slugs[i % len(slugs)] for i in range(n)]
+
+
+def build_deckies(
+    n: int,
+    ips: list[str],
+    services_explicit: list[str] | None,
+    randomize_services: bool,
+    distros_explicit: list[str] | None = None,
+    randomize_distros: bool = False,
+    archetype: Archetype | None = None,
+    mutate_interval: Optional[int] = None,
+) -> list[DeckyConfig]:
+    """Build a list of DeckyConfigs from CLI-style flags."""
+    deckies = []
+    used_combos: set[frozenset] = set()
+    distro_slugs = resolve_distros(distros_explicit, randomize_distros, n, archetype)
+
+    for i, ip in enumerate(ips):
+        name = f"decky-{i + 1:02d}"
+        distro = get_distro(distro_slugs[i])
+        hostname = random_hostname(distro.slug)
+
+        if services_explicit:
+            svc_list = services_explicit
+        elif archetype:
+            svc_list = list(archetype.services)
+        elif randomize_services:
+            svc_pool = all_service_names()
+            attempts = 0
+            while True:
+                count = random.randint(1, min(3, len(svc_pool)))  # nosec B311
+                chosen = frozenset(random.sample(svc_pool, count))  # nosec B311
+                attempts += 1
+                if chosen not in used_combos or attempts > 20:
+                    break
+            svc_list = list(chosen)
+            used_combos.add(chosen)
+        else:
+            raise ValueError("Provide services_explicit, archetype, or randomize_services=True.")
+
+        deckies.append(
+            DeckyConfig(
+                name=name,
+                ip=ip,
+                services=svc_list,
+                distro=distro.slug,
+                base_image=distro.image,
+                build_base=distro.build_base,
+                hostname=hostname,
+                archetype=archetype.slug if archetype else None,
+                nmap_os=archetype.nmap_os if archetype else "linux",
+                mutate_interval=mutate_interval,
+            )
+        )
+    return deckies
+
+
+def build_deckies_from_ini(
+    ini: IniConfig,
+    subnet_cidr: str,
+    gateway: str,
+    host_ip: str,
+    randomize: bool,
+    cli_mutate_interval: int | None = None,
+) -> list[DeckyConfig]:
+    """Build DeckyConfig list from an IniConfig, auto-allocating missing IPs."""
+    from ipaddress import IPv4Address, IPv4Network
+    import time
+    now = time.time()
+
+    explicit_ips: set[IPv4Address] = {
+        IPv4Address(s.ip) for s in ini.deckies if s.ip
+    }
+
+    net = IPv4Network(subnet_cidr, strict=False)
+    reserved = {
+        net.network_address,
+        net.broadcast_address,
+        IPv4Address(gateway),
+        IPv4Address(host_ip),
+    } | explicit_ips
+
+    auto_pool = (str(addr) for addr in net.hosts() if addr not in reserved)
+
+    deckies: list[DeckyConfig] = []
+    for spec in ini.deckies:
+        arch: Archetype | None = None
+        if spec.archetype:
+            arch = get_archetype(spec.archetype)
+
+        distro_pool = arch.preferred_distros if arch else list(all_distros().keys())
+        distro = get_distro(distro_pool[len(deckies) % len(distro_pool)])
+        hostname = random_hostname(distro.slug)
+
+        ip = spec.ip or next(auto_pool, None)
+        if ip is None:
+            raise ValueError(f"Not enough free IPs in {subnet_cidr} while assigning IP for '{spec.name}'.")
+
+        if spec.services:
+            known = set(all_service_names())
+            unknown = [s for s in spec.services if s not in known]
+            if unknown:
+                raise ValueError(
+                    f"Unknown service(s) in [{spec.name}]: {unknown}. "
+                    f"Available: {all_service_names()}"
+                )
+            svc_list = spec.services
+        elif arch:
+            svc_list = list(arch.services)
+        elif randomize:
+            svc_pool = all_service_names()
+            count = random.randint(1, min(3, len(svc_pool)))  # nosec B311
+            svc_list = random.sample(svc_pool, count)  # nosec B311
+        else:
+            raise ValueError(
+                f"Decky '[{spec.name}]' has no services= in config. "
+                "Add services=, archetype=, or use --randomize-services."
+            )
+
+        resolved_nmap_os = spec.nmap_os or (arch.nmap_os if arch else "linux")
+
+        decky_mutate_interval = cli_mutate_interval
+        if decky_mutate_interval is None:
+            decky_mutate_interval = spec.mutate_interval if spec.mutate_interval is not None else ini.mutate_interval
+
+        deckies.append(DeckyConfig(
+            name=spec.name,
+            ip=ip,
+            services=svc_list,
+            distro=distro.slug,
+            base_image=distro.image,
+            build_base=distro.build_base,
+            hostname=hostname,
+            archetype=arch.slug if arch else None,
+            service_config=spec.service_config,
+            nmap_os=resolved_nmap_os,
+            mutate_interval=decky_mutate_interval,
+            last_mutated=now,
+        ))
+    return deckies
diff --git a/decnet/mutator/__init__.py b/decnet/mutator/__init__.py
new file mode 100644
index 0000000..41d5792
--- /dev/null
+++ b/decnet/mutator/__init__.py
@@ -0,0 +1,3 @@
+from decnet.mutator.engine import mutate_all, mutate_decky, run_watch_loop
+
+__all__ = ["mutate_all", "mutate_decky", "run_watch_loop"]
diff --git a/decnet/mutator.py b/decnet/mutator/engine.py
similarity index 68%
rename from decnet/mutator.py
rename to decnet/mutator/engine.py
index 9cf857f..fbd3096 100644
--- a/decnet/mutator.py
+++ b/decnet/mutator/engine.py
@@ -4,43 +4,21 @@ Handles dynamic rotation of exposed honeypot services over time.
 """
 
 import random
-import subprocess  # nosec B404
 import time
-from pathlib import Path
 from typing import Optional
 
 from rich.console import Console
 
 from decnet.archetypes import get_archetype
-from decnet.cli import _all_service_names
+from decnet.fleet import all_service_names
 from decnet.composer import write_compose
 from decnet.config import DeckyConfig, load_state, save_state
-from decnet.deployer import COMPOSE_FILE
+from decnet.engine import COMPOSE_FILE, _compose_with_retry
+
+import subprocess  # nosec B404
 
 console = Console()
 
-def _compose_with_retry(
-    *args: str,
-    compose_file: Path = COMPOSE_FILE,
-    retries: int = 3,
-    delay: float = 5.0,
-) -> None:
-    """Run a docker compose command, retrying on transient failures."""
-    last_exc: subprocess.CalledProcessError | None = None
-    cmd = ["docker", "compose", "-f", str(compose_file), *args]
-    for attempt in range(1, retries + 1):
-        result = subprocess.run(cmd, capture_output=True, text=True)  # nosec B603
-        if result.returncode == 0:
-            if result.stdout:
-                print(result.stdout, end="")
-            return
-        last_exc = subprocess.CalledProcessError(
-            result.returncode, cmd, result.stdout, result.stderr
-        )
-        if attempt < retries:
-            time.sleep(delay)
-            delay *= 2
-    raise last_exc
 
 def mutate_decky(decky_name: str) -> bool:
     """
@@ -59,23 +37,21 @@ def mutate_decky(decky_name: str) -> bool:
         console.print(f"[red]Decky '{decky_name}' not found in state.[/]")
         return False
 
-    # Determine allowed services pool
     if decky.archetype:
         try:
             arch = get_archetype(decky.archetype)
             svc_pool = list(arch.services)
         except ValueError:
-            svc_pool = _all_service_names()
+            svc_pool = all_service_names()
     else:
-        svc_pool = _all_service_names()
+        svc_pool = all_service_names()
 
     if not svc_pool:
         console.print(f"[yellow]No services available for mutating '{decky_name}'.[/]")
         return False
 
-    # Prevent mutating to the exact same set if possible
     current_services = set(decky.services)
-    
+
     attempts = 0
     while True:
         count = random.randint(1, min(3, len(svc_pool)))  # nosec B311
@@ -87,15 +63,11 @@ def mutate_decky(decky_name: str) -> bool:
     decky.services = list(chosen)
     decky.last_mutated = time.time()
 
-    # Save new state
     save_state(config, compose_path)
-
-    # Regenerate compose file
     write_compose(config, compose_path)
 
     console.print(f"[cyan]Mutating '{decky_name}' to services: {', '.join(decky.services)}[/]")
 
-    # Bring up the new services and remove old orphans
     try:
         _compose_with_retry("up", "-d", "--remove-orphans", compose_file=compose_path)
     except subprocess.CalledProcessError as e:
@@ -104,6 +76,7 @@ def mutate_decky(decky_name: str) -> bool:
 
     return True
 
+
 def mutate_all(force: bool = False) -> None:
     """
     Check all deckies and mutate those that are due.
@@ -116,7 +89,7 @@ def mutate_all(force: bool = False) -> None:
 
     config, _ = state
     now = time.time()
-    
+
     mutated_count = 0
     for decky in config.deckies:
         interval_mins = decky.mutate_interval or config.mutate_interval
@@ -133,14 +106,11 @@ def mutate_all(force: bool = False) -> None:
             success = mutate_decky(decky.name)
             if success:
                 mutated_count += 1
-            # Re-load state for next decky just in case, but mutate_decky saves it.
-            # However, mutate_decky operates on its own loaded state.
-            # Since mutate_decky loads and saves the state, our loop over `config.deckies`
-            # has an outdated `last_mutated` if we don't reload. It's fine because we process one by one.
-    
+
     if mutated_count == 0 and not force:
         console.print("[dim]No deckies are due for mutation.[/]")
 
+
 def run_watch_loop(poll_interval_secs: int = 10) -> None:
     """Run an infinite loop checking for deckies that need mutation."""
     console.print(f"[green]DECNET Mutator Watcher started (polling every {poll_interval_secs}s).[/]")
diff --git a/decnet/web/api.py b/decnet/web/api.py
index abefa65..29529df 100644
--- a/decnet/web/api.py
+++ b/decnet/web/api.py
@@ -9,7 +9,7 @@ from fastapi.middleware.cors import CORSMiddleware
 
 from decnet.env import DECNET_CORS_ORIGINS, DECNET_DEVELOPER, DECNET_INGEST_LOG_FILE
 from decnet.web.dependencies import repo
-from decnet.web.collector import log_collector_worker
+from decnet.collector import log_collector_worker
 from decnet.web.ingester import log_ingestion_worker
 from decnet.web.router import api_router
 
diff --git a/decnet/web/router/fleet/api_deploy_deckies.py b/decnet/web/router/fleet/api_deploy_deckies.py
index bbe7d1d..c6d011d 100644
--- a/decnet/web/router/fleet/api_deploy_deckies.py
+++ b/decnet/web/router/fleet/api_deploy_deckies.py
@@ -4,7 +4,7 @@ import os
 from fastapi import APIRouter, Depends, HTTPException
 
 from decnet.config import DEFAULT_MUTATE_INTERVAL, DecnetConfig, load_state
-from decnet.deployer import deploy as _deploy
+from decnet.engine import deploy as _deploy
 from decnet.ini_loader import load_ini_from_string
 from decnet.network import detect_interface, detect_subnet, get_host_ip
 from decnet.web.dependencies import get_current_user
@@ -15,7 +15,7 @@ router = APIRouter()
 
 @router.post("/deckies/deploy", tags=["Fleet Management"])
 async def api_deploy_deckies(req: DeployIniRequest, current_user: str = Depends(get_current_user)) -> dict[str, str]:
-    from decnet.cli import _build_deckies_from_ini
+    from decnet.fleet import build_deckies_from_ini
 
     try:
         ini = load_ini_from_string(req.ini_content)
@@ -56,7 +56,7 @@ async def api_deploy_deckies(req: DeployIniRequest, current_user: str = Depends(
         )
 
     try:
-        new_decky_configs = _build_deckies_from_ini(
+        new_decky_configs = build_deckies_from_ini(
             ini, subnet_cidr, gateway, host_ip, randomize_services, cli_mutate_interval=None
         )
     except ValueError as e:
diff --git a/tests/test_archetypes.py b/tests/test_archetypes.py
index 1304420..f5a18c9 100644
--- a/tests/test_archetypes.py
+++ b/tests/test_archetypes.py
@@ -266,7 +266,7 @@ def test_ini_subsection_direct_match_unaffected():
 # ---------------------------------------------------------------------------
 
 def test_build_deckies_archetype_sets_services():
-    from decnet.cli import _build_deckies
+    from decnet.fleet import build_deckies as _build_deckies
     from decnet.archetypes import get_archetype
     arch = get_archetype("mail-server")
     result = _build_deckies(
@@ -283,7 +283,7 @@ def test_build_deckies_archetype_sets_services():
 
 
 def test_build_deckies_archetype_preferred_distros():
-    from decnet.cli import _build_deckies
+    from decnet.fleet import build_deckies as _build_deckies
     from decnet.archetypes import get_archetype
     arch = get_archetype("iot-device")  # preferred_distros=["alpine"]
     result = _build_deckies(
@@ -298,7 +298,7 @@ def test_build_deckies_archetype_preferred_distros():
 
 
 def test_build_deckies_explicit_services_override_archetype():
-    from decnet.cli import _build_deckies
+    from decnet.fleet import build_deckies as _build_deckies
     from decnet.archetypes import get_archetype
     arch = get_archetype("linux-server")
     result = _build_deckies(
diff --git a/tests/test_build.py b/tests/test_build.py
index fbdc185..7062bb5 100644
--- a/tests/test_build.py
+++ b/tests/test_build.py
@@ -8,7 +8,13 @@ MODULES = [
     "decnet.cli",
     "decnet.config",
     "decnet.composer",
-    "decnet.deployer",
+    "decnet.engine",
+    "decnet.engine.deployer",
+    "decnet.collector",
+    "decnet.collector.worker",
+    "decnet.mutator",
+    "decnet.mutator.engine",
+    "decnet.fleet",
     "decnet.network",
     "decnet.archetypes",
     "decnet.distros",
diff --git a/tests/test_cli_service_pool.py b/tests/test_cli_service_pool.py
index 84c9387..6c673a3 100644
--- a/tests/test_cli_service_pool.py
+++ b/tests/test_cli_service_pool.py
@@ -3,7 +3,7 @@ Tests for the CLI service pool — verifies that --randomize-services draws
 from all registered services, not just the original hardcoded 5.
 """
 
-from decnet.cli import _all_service_names, _build_deckies
+from decnet.fleet import all_service_names as _all_service_names, build_deckies as _build_deckies
 from decnet.services.registry import all_services
 
 
diff --git a/tests/test_collector.py b/tests/test_collector.py
index 5157f2e..edef7f2 100644
--- a/tests/test_collector.py
+++ b/tests/test_collector.py
@@ -3,7 +3,7 @@
 import json
 from types import SimpleNamespace
 from unittest.mock import patch
-from decnet.web.collector import parse_rfc5424, is_service_container, is_service_event
+from decnet.collector import parse_rfc5424, is_service_container, is_service_event
 
 _KNOWN_NAMES = {"omega-decky-http", "omega-decky-smtp", "relay-decky-ftp"}
 
@@ -91,42 +91,42 @@ class TestParseRfc5424:
 
 class TestIsServiceContainer:
     def test_known_container_returns_true(self):
-        with patch("decnet.web.collector._load_service_container_names", return_value=_KNOWN_NAMES):
+        with patch("decnet.collector.worker._load_service_container_names", return_value=_KNOWN_NAMES):
             assert is_service_container(_make_container("omega-decky-http")) is True
             assert is_service_container(_make_container("omega-decky-smtp")) is True
             assert is_service_container(_make_container("relay-decky-ftp")) is True
 
     def test_base_container_returns_false(self):
-        with patch("decnet.web.collector._load_service_container_names", return_value=_KNOWN_NAMES):
+        with patch("decnet.collector.worker._load_service_container_names", return_value=_KNOWN_NAMES):
             assert is_service_container(_make_container("omega-decky")) is False
 
     def test_unrelated_container_returns_false(self):
-        with patch("decnet.web.collector._load_service_container_names", return_value=_KNOWN_NAMES):
+        with patch("decnet.collector.worker._load_service_container_names", return_value=_KNOWN_NAMES):
             assert is_service_container(_make_container("nginx")) is False
 
     def test_strips_leading_slash(self):
-        with patch("decnet.web.collector._load_service_container_names", return_value=_KNOWN_NAMES):
+        with patch("decnet.collector.worker._load_service_container_names", return_value=_KNOWN_NAMES):
             assert is_service_container(_make_container("/omega-decky-http")) is True
             assert is_service_container(_make_container("/omega-decky")) is False
 
     def test_no_state_returns_false(self):
-        with patch("decnet.web.collector._load_service_container_names", return_value=set()):
+        with patch("decnet.collector.worker._load_service_container_names", return_value=set()):
             assert is_service_container(_make_container("omega-decky-http")) is False
 
 
 class TestIsServiceEvent:
     def test_known_service_event_returns_true(self):
-        with patch("decnet.web.collector._load_service_container_names", return_value=_KNOWN_NAMES):
+        with patch("decnet.collector.worker._load_service_container_names", return_value=_KNOWN_NAMES):
             assert is_service_event({"name": "omega-decky-smtp"}) is True
 
     def test_base_event_returns_false(self):
-        with patch("decnet.web.collector._load_service_container_names", return_value=_KNOWN_NAMES):
+        with patch("decnet.collector.worker._load_service_container_names", return_value=_KNOWN_NAMES):
             assert is_service_event({"name": "omega-decky"}) is False
 
     def test_unrelated_event_returns_false(self):
-        with patch("decnet.web.collector._load_service_container_names", return_value=_KNOWN_NAMES):
+        with patch("decnet.collector.worker._load_service_container_names", return_value=_KNOWN_NAMES):
             assert is_service_event({"name": "nginx"}) is False
 
     def test_no_state_returns_false(self):
-        with patch("decnet.web.collector._load_service_container_names", return_value=set()):
+        with patch("decnet.collector.worker._load_service_container_names", return_value=set()):
             assert is_service_event({"name": "omega-decky-smtp"}) is False
diff --git a/tests/test_mutator.py b/tests/test_mutator.py
index f81d7ac..9872883 100644
--- a/tests/test_mutator.py
+++ b/tests/test_mutator.py
@@ -10,7 +10,8 @@ from unittest.mock import MagicMock, patch
 import pytest
 
 from decnet.config import DeckyConfig, DecnetConfig
-from decnet.mutator import _compose_with_retry, mutate_all, mutate_decky
+from decnet.engine import _compose_with_retry
+from decnet.mutator import mutate_all, mutate_decky
 
 
 # ---------------------------------------------------------------------------
@@ -48,37 +49,37 @@ def _make_config(deckies=None, mutate_interval=30):
 class TestComposeWithRetry:
     def test_succeeds_on_first_attempt(self):
         result = MagicMock(returncode=0, stdout="done\n")
-        with patch("decnet.mutator.subprocess.run", return_value=result) as mock_run:
+        with patch("decnet.engine.deployer.subprocess.run", return_value=result) as mock_run:
             _compose_with_retry("up", "-d", compose_file=Path("compose.yml"))
         mock_run.assert_called_once()
 
     def test_retries_on_failure_then_succeeds(self):
         fail = MagicMock(returncode=1, stdout="", stderr="transient error")
         ok   = MagicMock(returncode=0, stdout="", stderr="")
-        with patch("decnet.mutator.subprocess.run", side_effect=[fail, ok]) as mock_run, \
-             patch("decnet.mutator.time.sleep"):
+        with patch("decnet.engine.deployer.subprocess.run", side_effect=[fail, ok]) as mock_run, \
+             patch("decnet.engine.deployer.time.sleep"):
             _compose_with_retry("up", "-d", compose_file=Path("compose.yml"), retries=3)
         assert mock_run.call_count == 2
 
     def test_raises_after_all_retries_exhausted(self):
         fail = MagicMock(returncode=1, stdout="", stderr="hard error")
-        with patch("decnet.mutator.subprocess.run", return_value=fail), \
-             patch("decnet.mutator.time.sleep"):
+        with patch("decnet.engine.deployer.subprocess.run", return_value=fail), \
+             patch("decnet.engine.deployer.time.sleep"):
             with pytest.raises(subprocess.CalledProcessError):
                 _compose_with_retry("up", "-d", compose_file=Path("compose.yml"), retries=3)
 
     def test_exponential_backoff(self):
         fail = MagicMock(returncode=1, stdout="", stderr="")
         sleep_calls = []
-        with patch("decnet.mutator.subprocess.run", return_value=fail), \
-             patch("decnet.mutator.time.sleep", side_effect=lambda d: sleep_calls.append(d)):
+        with patch("decnet.engine.deployer.subprocess.run", return_value=fail), \
+             patch("decnet.engine.deployer.time.sleep", side_effect=lambda d: sleep_calls.append(d)):
             with pytest.raises(subprocess.CalledProcessError):
                 _compose_with_retry("up", compose_file=Path("c.yml"), retries=3, delay=1.0)
         assert sleep_calls == [1.0, 2.0]
 
     def test_correct_command_structure(self):
         ok = MagicMock(returncode=0, stdout="")
-        with patch("decnet.mutator.subprocess.run", return_value=ok) as mock_run:
+        with patch("decnet.engine.deployer.subprocess.run", return_value=ok) as mock_run:
             _compose_with_retry("up", "-d", "--remove-orphans",
                                 compose_file=Path("/tmp/compose.yml"))
         cmd = mock_run.call_args[0][0]
@@ -96,14 +97,14 @@ class TestMutateDecky:
         """Return a context manager that mocks all I/O in mutate_decky."""
         cfg = config or _make_config()
         return (
-            patch("decnet.mutator.load_state", return_value=(cfg, compose_path)),
-            patch("decnet.mutator.save_state"),
-            patch("decnet.mutator.write_compose"),
-            patch("decnet.mutator._compose_with_retry"),
+            patch("decnet.mutator.engine.load_state", return_value=(cfg, compose_path)),
+            patch("decnet.mutator.engine.save_state"),
+            patch("decnet.mutator.engine.write_compose"),
+            patch("decnet.mutator.engine._compose_with_retry"),
         )
 
     def test_returns_false_when_no_state(self):
-        with patch("decnet.mutator.load_state", return_value=None):
+        with patch("decnet.mutator.engine.load_state", return_value=None):
             assert mutate_decky("decky-01") is False
 
     def test_returns_false_when_decky_not_found(self):
@@ -118,20 +119,20 @@ class TestMutateDecky:
 
     def test_saves_state_after_mutation(self):
         p = self._patch()
-        with p[0], patch("decnet.mutator.save_state") as mock_save, p[2], p[3]:
+        with p[0], patch("decnet.mutator.engine.save_state") as mock_save, p[2], p[3]:
             mutate_decky("decky-01")
         mock_save.assert_called_once()
 
     def test_regenerates_compose_after_mutation(self):
         p = self._patch()
-        with p[0], p[1], patch("decnet.mutator.write_compose") as mock_compose, p[3]:
+        with p[0], p[1], patch("decnet.mutator.engine.write_compose") as mock_compose, p[3]:
             mutate_decky("decky-01")
         mock_compose.assert_called_once()
 
     def test_returns_false_on_compose_failure(self):
         p = self._patch()
         err = subprocess.CalledProcessError(1, "docker", "", "compose failed")
-        with p[0], p[1], p[2], patch("decnet.mutator._compose_with_retry", side_effect=err):
+        with p[0], p[1], p[2], patch("decnet.mutator.engine._compose_with_retry", side_effect=err):
             assert mutate_decky("decky-01") is False
 
     def test_mutation_changes_services(self):
@@ -166,15 +167,15 @@ class TestMutateDecky:
 
 class TestMutateAll:
     def test_no_state_returns_early(self):
-        with patch("decnet.mutator.load_state", return_value=None), \
-             patch("decnet.mutator.mutate_decky") as mock_mutate:
+        with patch("decnet.mutator.engine.load_state", return_value=None), \
+             patch("decnet.mutator.engine.mutate_decky") as mock_mutate:
             mutate_all()
         mock_mutate.assert_not_called()
 
     def test_force_mutates_all_deckies(self):
         cfg = _make_config(deckies=[_make_decky("d1"), _make_decky("d2")])
-        with patch("decnet.mutator.load_state", return_value=(cfg, Path("c.yml"))), \
-             patch("decnet.mutator.mutate_decky", return_value=True) as mock_mutate:
+        with patch("decnet.mutator.engine.load_state", return_value=(cfg, Path("c.yml"))), \
+             patch("decnet.mutator.engine.mutate_decky", return_value=True) as mock_mutate:
             mutate_all(force=True)
         assert mock_mutate.call_count == 2
 
@@ -182,8 +183,8 @@ class TestMutateAll:
         # last_mutated = now, interval = 30 min → not due
         now = time.time()
         cfg = _make_config(deckies=[_make_decky(mutate_interval=30, last_mutated=now)])
-        with patch("decnet.mutator.load_state", return_value=(cfg, Path("c.yml"))), \
-             patch("decnet.mutator.mutate_decky") as mock_mutate:
+        with patch("decnet.mutator.engine.load_state", return_value=(cfg, Path("c.yml"))), \
+             patch("decnet.mutator.engine.mutate_decky") as mock_mutate:
             mutate_all(force=False)
         mock_mutate.assert_not_called()
 
@@ -191,8 +192,8 @@ class TestMutateAll:
         # last_mutated = 2 hours ago, interval = 30 min → due
         old_ts = time.time() - 7200
         cfg = _make_config(deckies=[_make_decky(mutate_interval=30, last_mutated=old_ts)])
-        with patch("decnet.mutator.load_state", return_value=(cfg, Path("c.yml"))), \
-             patch("decnet.mutator.mutate_decky", return_value=True) as mock_mutate:
+        with patch("decnet.mutator.engine.load_state", return_value=(cfg, Path("c.yml"))), \
+             patch("decnet.mutator.engine.mutate_decky", return_value=True) as mock_mutate:
             mutate_all(force=False)
         mock_mutate.assert_called_once_with("decky-01")
 
@@ -201,7 +202,7 @@ class TestMutateAll:
             deckies=[_make_decky(mutate_interval=None)],
             mutate_interval=None,
         )
-        with patch("decnet.mutator.load_state", return_value=(cfg, Path("c.yml"))), \
-             patch("decnet.mutator.mutate_decky") as mock_mutate:
+        with patch("decnet.mutator.engine.load_state", return_value=(cfg, Path("c.yml"))), \
+             patch("decnet.mutator.engine.mutate_decky") as mock_mutate:
             mutate_all(force=False)
         mock_mutate.assert_not_called()
diff --git a/tests/test_os_fingerprint.py b/tests/test_os_fingerprint.py
index 79e3438..5193716 100644
--- a/tests/test_os_fingerprint.py
+++ b/tests/test_os_fingerprint.py
@@ -434,7 +434,7 @@ def test_compose_embedded_sysctls_full_set():
 
 def test_build_deckies_windows_archetype_sets_nmap_os():
     from decnet.archetypes import get_archetype
-    from decnet.cli import _build_deckies
+    from decnet.fleet import build_deckies as _build_deckies
 
     arch = get_archetype("windows-workstation")
     deckies = _build_deckies(
@@ -448,7 +448,7 @@ def test_build_deckies_windows_archetype_sets_nmap_os():
 
 
 def test_build_deckies_no_archetype_defaults_linux():
-    from decnet.cli import _build_deckies
+    from decnet.fleet import build_deckies as _build_deckies
 
     deckies = _build_deckies(
         n=1,
@@ -462,7 +462,7 @@ def test_build_deckies_no_archetype_defaults_linux():
 
 def test_build_deckies_embedded_archetype_sets_nmap_os():
     from decnet.archetypes import get_archetype
-    from decnet.cli import _build_deckies
+    from decnet.fleet import build_deckies as _build_deckies
 
     arch = get_archetype("iot-device")
     deckies = _build_deckies(