diff --git a/masque/builder/builder.py b/masque/builder/builder.py
index 1b534b5..3c39710 100644
--- a/masque/builder/builder.py
+++ b/masque/builder/builder.py
@@ -284,8 +284,7 @@ class Builder(PortList):
                 do not line up)
         """
         if self._dead:
-            logger.error('Skipping plug() since device is dead')
-            return self
+            logger.warning('Skipping geometry for plug() since device is dead')
 
         if not isinstance(other, str | Abstract | Pattern):
             # We got a Tree; add it into self.library and grab an Abstract for it
@@ -305,6 +304,7 @@ class Builder(PortList):
             set_rotation = set_rotation,
             append = append,
             ok_connections = ok_connections,
+            skip_geometry = self._dead,
             )
         return self
 
@@ -357,8 +357,7 @@ class Builder(PortList):
                 are applied.
         """
         if self._dead:
-            logger.error('Skipping place() since device is dead')
-            return self
+            logger.warning('Skipping geometry for place() since device is dead')
 
         if not isinstance(other, str | Abstract | Pattern):
             # We got a Tree; add it into self.library and grab an Abstract for it
@@ -378,6 +377,7 @@ class Builder(PortList):
             port_map = port_map,
             skip_port_check = skip_port_check,
             append = append,
+            skip_geometry = self._dead,
             )
         return self
 
diff --git a/masque/builder/pather.py b/masque/builder/pather.py
index 9af473d..d58b282 100644
--- a/masque/builder/pather.py
+++ b/masque/builder/pather.py
@@ -7,6 +7,8 @@ import copy
 import logging
 from pprint import pformat
 
+from numpy import pi
+
 from ..pattern import Pattern
 from ..library import ILibrary
 from ..error import BuildError
@@ -288,14 +290,36 @@ class Pather(Builder, PatherMixin):
             LibraryError if no valid name could be picked for the pattern.
         """
         if self._dead:
-            logger.error('Skipping path() since device is dead')
-            return self
+            logger.warning('Skipping geometry for path() since device is dead')
 
         tool_port_names = ('A', 'B')
 
         tool = self.tools.get(portspec, self.tools[None])
         in_ptype = self.pattern[portspec].ptype
-        tree = tool.path(ccw, length, in_ptype=in_ptype, port_names=tool_port_names, **kwargs)
+        try:
+            tree = tool.path(ccw, length, in_ptype=in_ptype, port_names=tool_port_names, **kwargs)
+        except (BuildError, NotImplementedError):
+            if not self._dead:
+                raise
+            logger.warning("Tool path failed for dead pather. Using dummy extension.")
+            # Fallback for dead pather: manually update the port instead of plugging
+            port = self.pattern[portspec]
+            port_rot = port.rotation
+            if ccw is None:
+                out_rot = pi
+            elif bool(ccw):
+                out_rot = -pi / 2
+            else:
+                out_rot = pi / 2
+            out_port = Port((length, 0), rotation=out_rot, ptype=in_ptype)
+            out_port.rotate_around((0, 0), pi + port_rot)
+            out_port.translate(port.offset)
+            self.pattern.ports[portspec] = out_port
+            self._log_port_update(portspec)
+            if plug_into is not None:
+                self.plugged({portspec: plug_into})
+            return self
+
         tname = self.library << tree
         if plug_into is not None:
             output = {plug_into: tool_port_names[1]}
@@ -340,8 +364,7 @@ class Pather(Builder, PatherMixin):
             LibraryError if no valid name could be picked for the pattern.
         """
         if self._dead:
-            logger.error('Skipping pathS() since device is dead')
-            return self
+            logger.warning('Skipping geometry for pathS() since device is dead')
 
         tool_port_names = ('A', 'B')
 
@@ -353,16 +376,39 @@ class Pather(Builder, PatherMixin):
             # Fall back to drawing two L-bends
             ccw0 = jog > 0
             kwargs_no_out = kwargs | {'out_ptype': None}
-            t_tree0 = tool.path(    ccw0, length / 2, port_names=tool_port_names, in_ptype=in_ptype, **kwargs_no_out)
-            t_pat0 = t_tree0.top_pattern()
-            (_, jog0), _ = t_pat0[tool_port_names[0]].measure_travel(t_pat0[tool_port_names[1]])
-            t_tree1 = tool.path(not ccw0, abs(jog - jog0), port_names=tool_port_names, in_ptype=t_pat0[tool_port_names[1]].ptype, **kwargs)
-            t_pat1 = t_tree1.top_pattern()
-            (_, jog1), _ = t_pat1[tool_port_names[0]].measure_travel(t_pat1[tool_port_names[1]])
+            try:
+                t_tree0 = tool.path(    ccw0, length / 2, port_names=tool_port_names, in_ptype=in_ptype, **kwargs_no_out)
+                t_pat0 = t_tree0.top_pattern()
+                (_, jog0), _ = t_pat0[tool_port_names[0]].measure_travel(t_pat0[tool_port_names[1]])
+                t_tree1 = tool.path(not ccw0, abs(jog - jog0), port_names=tool_port_names, in_ptype=t_pat0[tool_port_names[1]].ptype, **kwargs)
+                t_pat1 = t_tree1.top_pattern()
+                (_, jog1), _ = t_pat1[tool_port_names[0]].measure_travel(t_pat1[tool_port_names[1]])
 
-            kwargs_plug = kwargs | {'plug_into': plug_into}
-            self.path(portspec,     ccw0, length - abs(jog1), **kwargs_no_out)
-            self.path(portspec, not ccw0,    abs(jog - jog0), **kwargs_plug)
+                kwargs_plug = kwargs | {'plug_into': plug_into}
+                self.path(portspec,     ccw0, length - abs(jog1), **kwargs_no_out)
+                self.path(portspec, not ccw0,    abs(jog - jog0), **kwargs_plug)
+                return self
+            except (BuildError, NotImplementedError):
+                if not self._dead:
+                    raise
+                # Fall through to dummy extension below
+        except BuildError:
+            if not self._dead:
+                raise
+            # Fall through to dummy extension below
+
+        if self._dead:
+            logger.warning("Tool pathS failed for dead pather. Using dummy extension.")
+            # Fallback for dead pather: manually update the port instead of plugging
+            port = self.pattern[portspec]
+            port_rot = port.rotation
+            out_port = Port((length, jog), rotation=pi, ptype=in_ptype)
+            out_port.rotate_around((0, 0), pi + port_rot)
+            out_port.translate(port.offset)
+            self.pattern.ports[portspec] = out_port
+            self._log_port_update(portspec)
+            if plug_into is not None:
+                self.plugged({portspec: plug_into})
             return self
 
         tname = self.library << tree
diff --git a/masque/builder/renderpather.py b/masque/builder/renderpather.py
index 4bc3b5f..863f3f1 100644
--- a/masque/builder/renderpather.py
+++ b/masque/builder/renderpather.py
@@ -253,8 +253,7 @@ class RenderPather(PatherMixin):
                 do not line up)
         """
         if self._dead:
-            logger.error('Skipping plug() since device is dead')
-            return self
+            logger.warning('Skipping geometry for plug() since device is dead')
 
         other_tgt: Pattern | Abstract
         if isinstance(other, str):
@@ -262,18 +261,19 @@ class RenderPather(PatherMixin):
         if append and isinstance(other, Abstract):
             other_tgt = self.library[other.name]
 
-        # get rid of plugged ports
-        for kk in map_in:
-            if kk in self.paths:
-                self.paths[kk].append(RenderStep('P', None, self.ports[kk].copy(), self.ports[kk].copy(), None))
+        if not self._dead:
+            # get rid of plugged ports
+            for kk in map_in:
+                if kk in self.paths:
+                    self.paths[kk].append(RenderStep('P', None, self.ports[kk].copy(), self.ports[kk].copy(), None))
 
-        plugged = map_in.values()
-        for name, port in other_tgt.ports.items():
-            if name in plugged:
-                continue
-            new_name = map_out.get(name, name) if map_out is not None else name
-            if new_name is not None and new_name in self.paths:
-                self.paths[new_name].append(RenderStep('P', None, port.copy(), port.copy(), None))
+            plugged = map_in.values()
+            for name, port in other_tgt.ports.items():
+                if name in plugged:
+                    continue
+                new_name = map_out.get(name, name) if map_out is not None else name
+                if new_name is not None and new_name in self.paths:
+                    self.paths[new_name].append(RenderStep('P', None, port.copy(), port.copy(), None))
 
         self.pattern.plug(
             other = other_tgt,
@@ -284,6 +284,7 @@ class RenderPather(PatherMixin):
             set_rotation = set_rotation,
             append = append,
             ok_connections = ok_connections,
+            skip_geometry = self._dead,
             )
 
         return self
@@ -334,8 +335,7 @@ class RenderPather(PatherMixin):
                 are applied.
         """
         if self._dead:
-            logger.error('Skipping place() since device is dead')
-            return self
+            logger.warning('Skipping geometry for place() since device is dead')
 
         other_tgt: Pattern | Abstract
         if isinstance(other, str):
@@ -343,10 +343,11 @@ class RenderPather(PatherMixin):
         if append and isinstance(other, Abstract):
             other_tgt = self.library[other.name]
 
-        for name, port in other_tgt.ports.items():
-            new_name = port_map.get(name, name) if port_map is not None else name
-            if new_name is not None and new_name in self.paths:
-                self.paths[new_name].append(RenderStep('P', None, port.copy(), port.copy(), None))
+        if not self._dead:
+            for name, port in other_tgt.ports.items():
+                new_name = port_map.get(name, name) if port_map is not None else name
+                if new_name is not None and new_name in self.paths:
+                    self.paths[new_name].append(RenderStep('P', None, port.copy(), port.copy(), None))
 
         self.pattern.place(
             other = other_tgt,
@@ -357,6 +358,7 @@ class RenderPather(PatherMixin):
             port_map = port_map,
             skip_port_check = skip_port_check,
             append = append,
+            skip_geometry = self._dead,
             )
 
         return self
@@ -365,11 +367,12 @@ class RenderPather(PatherMixin):
             self,
             connections: dict[str, str],
             ) -> Self:
-        for aa, bb in connections.items():
-            porta = self.ports[aa]
-            portb = self.ports[bb]
-            self.paths[aa].append(RenderStep('P', None, porta.copy(), porta.copy(), None))
-            self.paths[bb].append(RenderStep('P', None, portb.copy(), portb.copy(), None))
+        if not self._dead:
+            for aa, bb in connections.items():
+                porta = self.ports[aa]
+                portb = self.ports[bb]
+                self.paths[aa].append(RenderStep('P', None, porta.copy(), porta.copy(), None))
+                self.paths[bb].append(RenderStep('P', None, portb.copy(), portb.copy(), None))
         PortList.plugged(self, connections)
         return self
 
@@ -410,8 +413,7 @@ class RenderPather(PatherMixin):
             LibraryError if no valid name could be picked for the pattern.
         """
         if self._dead:
-            logger.error('Skipping path() since device is dead')
-            return self
+            logger.warning('Skipping geometry for path() since device is dead')
 
         port = self.pattern[portspec]
         in_ptype = port.ptype
@@ -420,14 +422,28 @@ class RenderPather(PatherMixin):
 
         tool = self.tools.get(portspec, self.tools[None])
         # ask the tool for bend size (fill missing dx or dy), check feasibility, and get out_ptype
-        out_port, data = tool.planL(ccw, length, in_ptype=in_ptype, **kwargs)
+        try:
+            out_port, data = tool.planL(ccw, length, in_ptype=in_ptype, **kwargs)
+        except (BuildError, NotImplementedError):
+            if not self._dead:
+                raise
+            logger.warning("Tool planning failed for dead pather. Using dummy extension.")
+            if ccw is None:
+                out_rot = pi
+            elif bool(ccw):
+                out_rot = -pi / 2
+            else:
+                out_rot = pi / 2
+            out_port = Port((length, 0), rotation=out_rot, ptype=in_ptype)
+            data = None
 
         # Update port
         out_port.rotate_around((0, 0), pi + port_rot)
         out_port.translate(port.offset)
 
-        step = RenderStep('L', tool, port.copy(), out_port.copy(), data)
-        self.paths[portspec].append(step)
+        if not self._dead:
+            step = RenderStep('L', tool, port.copy(), out_port.copy(), data)
+            self.paths[portspec].append(step)
 
         self.pattern.ports[portspec] = out_port.copy()
         self._log_port_update(portspec)
@@ -475,8 +491,7 @@ class RenderPather(PatherMixin):
             LibraryError if no valid name could be picked for the pattern.
         """
         if self._dead:
-            logger.error('Skipping pathS() since device is dead')
-            return self
+            logger.warning('Skipping geometry for pathS() since device is dead')
 
         port = self.pattern[portspec]
         in_ptype = port.ptype
@@ -492,22 +507,38 @@ class RenderPather(PatherMixin):
             # Fall back to drawing two L-bends
             ccw0 = jog > 0
             kwargs_no_out = (kwargs | {'out_ptype': None})
-            t_port0, _ = tool.planL(    ccw0, length / 2, in_ptype=in_ptype, **kwargs_no_out)       # TODO length/2 may fail with asymmetric ptypes
-            jog0 = Port((0, 0), 0).measure_travel(t_port0)[0][1]
-            t_port1, _ = tool.planL(not ccw0, abs(jog - jog0), in_ptype=t_port0.ptype, **kwargs)
-            jog1 = Port((0, 0), 0).measure_travel(t_port1)[0][1]
+            try:
+                t_port0, _ = tool.planL(    ccw0, length / 2, in_ptype=in_ptype, **kwargs_no_out)       # TODO length/2 may fail with asymmetric ptypes
+                jog0 = Port((0, 0), 0).measure_travel(t_port0)[0][1]
+                t_port1, _ = tool.planL(not ccw0, abs(jog - jog0), in_ptype=t_port0.ptype, **kwargs)
+                jog1 = Port((0, 0), 0).measure_travel(t_port1)[0][1]
 
-            kwargs_plug = kwargs | {'plug_into': plug_into}
-            self.path(portspec,     ccw0, length - abs(jog1), **kwargs_no_out)
-            self.path(portspec, not ccw0,    abs(jog - jog0), **kwargs_plug)
-            return self
+                kwargs_plug = kwargs | {'plug_into': plug_into}
+                self.path(portspec,     ccw0, length - abs(jog1), **kwargs_no_out)
+                self.path(portspec, not ccw0,    abs(jog - jog0), **kwargs_plug)
+                return self
+            except (BuildError, NotImplementedError):
+                if not self._dead:
+                    raise
+                # Fall through to dummy extension below
+        except BuildError:
+            if not self._dead:
+                raise
+            # Fall through to dummy extension below
 
-        out_port.rotate_around((0, 0), pi + port_rot)
-        out_port.translate(port.offset)
-        step = RenderStep('S', tool, port.copy(), out_port.copy(), data)
-        self.paths[portspec].append(step)
-        self.pattern.ports[portspec] = out_port.copy()
-        self._log_port_update(portspec)
+        if self._dead:
+            logger.warning("Tool planning failed for dead pather. Using dummy extension.")
+            out_port = Port((length, jog), rotation=pi, ptype=in_ptype)
+            data = None
+
+        if out_port is not None:
+            out_port.rotate_around((0, 0), pi + port_rot)
+            out_port.translate(port.offset)
+            if not self._dead:
+                step = RenderStep('S', tool, port.copy(), out_port.copy(), data)
+                self.paths[portspec].append(step)
+            self.pattern.ports[portspec] = out_port.copy()
+            self._log_port_update(portspec)
 
         if plug_into is not None:
             self.plugged({portspec: plug_into})
diff --git a/masque/pattern.py b/masque/pattern.py
index 05a8962..04780ec 100644
--- a/masque/pattern.py
+++ b/masque/pattern.py
@@ -1101,6 +1101,7 @@ class Pattern(PortList, AnnotatableImpl, Mirrorable):
             port_map: dict[str, str | None] | None = None,
             skip_port_check: bool = False,
             append: bool = False,
+            skip_geometry: bool = False,
             ) -> Self:
         """
         Instantiate or append the pattern `other` into the current pattern, adding its
@@ -1132,6 +1133,7 @@ class Pattern(PortList, AnnotatableImpl, Mirrorable):
             append: If `True`, `other` is appended instead of being referenced.
                 Note that this does not flatten  `other`, so its refs will still
                 be refs (now inside `self`).
+            skip_geometry: If `True`, only ports are added; geometry is skipped.
 
         Returns:
             self
@@ -1165,6 +1167,9 @@ class Pattern(PortList, AnnotatableImpl, Mirrorable):
             self.ports[name] = pp
             self._log_port_update(name)
 
+        if skip_geometry:
+            return self
+
         if append:
             if isinstance(other, Abstract):
                 raise PatternError('Must provide a full `Pattern` (not an `Abstract`) when appending!')
@@ -1222,6 +1227,7 @@ class Pattern(PortList, AnnotatableImpl, Mirrorable):
             set_rotation: bool | None = None,
             append: bool = False,
             ok_connections: Iterable[tuple[str, str]] = (),
+            skip_geometry: bool = False,
             ) -> Self:
         """
         Instantiate or append a pattern into the current pattern, connecting
@@ -1276,6 +1282,7 @@ class Pattern(PortList, AnnotatableImpl, Mirrorable):
                 any other ptypte. Non-allowed ptype connections will emit a
                 warning. Order is ignored, i.e. `(a, b)` is equivalent to
                 `(b, a)`.
+            skip_geometry: If `True`, only ports are updated; geometry is skipped.
 
         Returns:
             self
@@ -1308,13 +1315,32 @@ class Pattern(PortList, AnnotatableImpl, Mirrorable):
             map_out = {out_port_name: next(iter(map_in.keys()))}
 
         self.check_ports(other.ports.keys(), map_in, map_out)
-        translation, rotation, pivot = self.find_transform(
-            other,
-            map_in,
-            mirrored = mirrored,
-            set_rotation = set_rotation,
-            ok_connections = ok_connections,
-            )
+        try:
+            translation, rotation, pivot = self.find_transform(
+                other,
+                map_in,
+                mirrored = mirrored,
+                set_rotation = set_rotation,
+                ok_connections = ok_connections,
+                )
+        except PortError:
+            if not skip_geometry:
+                raise
+            logger.warning("Port transform failed for dead device. Using dummy transform.")
+            if map_in:
+                ki, vi = next(iter(map_in.items()))
+                s_port = self.ports[ki]
+                o_port = other.ports[vi].deepcopy()
+                if mirrored:
+                    o_port.mirror()
+                    o_port.offset[1] *= -1
+                translation = s_port.offset - o_port.offset
+                rotation = (s_port.rotation - o_port.rotation - pi) if (s_port.rotation is not None and o_port.rotation is not None) else 0
+                pivot = o_port.offset
+            else:
+                translation = numpy.zeros(2)
+                rotation = 0.0
+                pivot = numpy.zeros(2)
 
         # get rid of plugged ports
         for ki, vi in map_in.items():
@@ -1323,7 +1349,7 @@ class Pattern(PortList, AnnotatableImpl, Mirrorable):
             map_out[vi] = None
 
         if isinstance(other, Pattern):
-            assert append, 'Got a name (not an abstract) but was asked to reference (not append)'
+            assert append or skip_geometry, 'Got a name (not an abstract) but was asked to reference (not append)'
 
         self.place(
             other,
@@ -1334,6 +1360,7 @@ class Pattern(PortList, AnnotatableImpl, Mirrorable):
             port_map = map_out,
             skip_port_check = True,
             append = append,
+            skip_geometry = skip_geometry,
             )
         return self
 
diff --git a/masque/test/test_builder.py b/masque/test/test_builder.py
index 1b67c65..bfbd1df 100644
--- a/masque/test/test_builder.py
+++ b/masque/test/test_builder.py
@@ -73,3 +73,57 @@ def test_builder_set_dead() -> None:
 
     b.place("sub")
     assert not b.pattern.has_refs()
+
+
+def test_builder_dead_ports() -> None:
+    lib = Library()
+    pat = Pattern()
+    pat.ports['A'] = Port((0, 0), 0)
+    b = Builder(lib, pattern=pat)
+    b.set_dead()
+
+    # Attempt to plug a device where ports don't line up
+    # A has rotation 0, C has rotation 0. plug() expects opposing rotations (pi difference).
+    other = Pattern(ports={'C': Port((10, 10), 0), 'D': Port((20, 20), 0)})
+
+    # This should NOT raise PortError because b is dead
+    b.plug(other, map_in={'A': 'C'}, map_out={'D': 'B'})
+
+    # Port A should be removed, and Port B (renamed from D) should be added
+    assert 'A' not in b.ports
+    assert 'B' in b.ports
+
+    # Verify geometry was not added
+    assert not b.pattern.has_refs()
+    assert not b.pattern.has_shapes()
+
+
+def test_dead_plug_best_effort() -> None:
+    lib = Library()
+    pat = Pattern()
+    pat.ports['A'] = Port((0, 0), 0)
+    b = Builder(lib, pattern=pat)
+    b.set_dead()
+
+    # Device with multiple ports, none of which line up correctly
+    other = Pattern(ports={
+        'P1': Port((10, 10), 0),  # Wrong rotation (0 instead of pi)
+        'P2': Port((20, 20), pi)  # Correct rotation but wrong offset
+    })
+
+    # Try to plug. find_transform will fail.
+    # It should fall back to aligning the first pair ('A' and 'P1').
+    b.plug(other, map_in={'A': 'P1'}, map_out={'P2': 'B'})
+
+    assert 'A' not in b.ports
+    assert 'B' in b.ports
+
+    # Dummy transform aligns A (0,0) with P1 (10,10)
+    # A rotation 0, P1 rotation 0 -> rotation = (0 - 0 - pi) = -pi
+    # P2 (20,20) rotation pi:
+    # 1. Translate P2 so P1 is at origin: (20,20) - (10,10) = (10,10)
+    # 2. Rotate (10,10) by -pi: (-10,-10)
+    # 3. Translate by s_port.offset (0,0): (-10,-10)
+    assert_allclose(b.ports['B'].offset, [-10, -10], atol=1e-10)
+    # P2 rot pi + transform rot -pi = 0
+    assert_allclose(b.ports['B'].rotation, 0, atol=1e-10)
diff --git a/masque/test/test_pather.py b/masque/test/test_pather.py
index e1d28d8..336458f 100644
--- a/masque/test/test_pather.py
+++ b/masque/test/test_pather.py
@@ -81,3 +81,25 @@ def test_pather_at_chaining(pather_setup: tuple[Pather, PathTool, Library]) -> N
     # pi/2 (North) + CCW (90 deg) -> 0 (East)?
     # Actual behavior results in pi (West).
     assert_allclose(p.ports["start"].rotation, pi, atol=1e-10)
+
+
+def test_pather_dead_ports() -> None:
+    lib = Library()
+    tool = PathTool(layer=(1, 0), width=1)
+    p = Pather(lib, ports={"in": Port((0, 0), 0)}, tools=tool)
+    p.set_dead()
+
+    # Path with negative length (impossible for PathTool, would normally raise BuildError)
+    p.path("in", None, -10)
+
+    # Port 'in' should be updated by dummy extension despite tool failure
+    # port_rot=0, forward is -x. path(-10) means moving -10 in -x direction -> +10 in x.
+    assert_allclose(p.ports["in"].offset, [10, 0], atol=1e-10)
+
+    # Downstream path should work correctly using the dummy port location
+    p.path("in", None, 20)
+    # 10 + (-20) = -10
+    assert_allclose(p.ports["in"].offset, [-10, 0], atol=1e-10)
+
+    # Verify no geometry
+    assert not p.pattern.has_shapes()
diff --git a/masque/test/test_renderpather.py b/masque/test/test_renderpather.py
index b843066..3948214 100644
--- a/masque/test/test_renderpather.py
+++ b/masque/test/test_renderpather.py
@@ -73,3 +73,23 @@ def test_renderpather_retool(rpather_setup: tuple[RenderPather, PathTool, Librar
     # Different tools should cause different batches/shapes
     assert len(rp.pattern.shapes[(1, 0)]) == 1
     assert len(rp.pattern.shapes[(2, 0)]) == 1
+
+
+def test_renderpather_dead_ports() -> None:
+    lib = Library()
+    tool = PathTool(layer=(1, 0), width=1)
+    rp = RenderPather(lib, ports={"in": Port((0, 0), 0)}, tools=tool)
+    rp.set_dead()
+
+    # Impossible path
+    rp.path("in", None, -10)
+
+    # port_rot=0, forward is -x. path(-10) means moving -10 in -x direction -> +10 in x.
+    assert_allclose(rp.ports["in"].offset, [10, 0], atol=1e-10)
+
+    # Verify no render steps were added
+    assert len(rp.paths["in"]) == 0
+
+    # Verify no geometry
+    rp.render()
+    assert not rp.pattern.has_shapes()