diff --git a/.github/workflows/conda_build_lib.yml b/.github/workflows/conda_build_lib.yml
index 2c020b03..66562252 100644
--- a/.github/workflows/conda_build_lib.yml
+++ b/.github/workflows/conda_build_lib.yml
@@ -34,11 +34,11 @@ jobs:
     steps:
 
       # This step checks out a copy of your repository.
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
           fetch-depth: 0
 
-      - uses: actions/setup-python@v6
+      - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
         with:
           python-version: 3.12
 
diff --git a/.github/workflows/conda_build_proj.yml b/.github/workflows/conda_build_proj.yml
index 3eecc934..117861a7 100644
--- a/.github/workflows/conda_build_proj.yml
+++ b/.github/workflows/conda_build_proj.yml
@@ -38,11 +38,11 @@ jobs:
     steps:
 
       # This step checks out a copy of your repository.
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
           fetch-depth: 0
 
-      - uses: actions/setup-python@v6
+      - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
         with:
           python-version: 3.12
 
diff --git a/.github/workflows/conda_build_win.yml b/.github/workflows/conda_build_win.yml
index 38d08dd8..b24ac6f6 100644
--- a/.github/workflows/conda_build_win.yml
+++ b/.github/workflows/conda_build_win.yml
@@ -30,11 +30,11 @@ jobs:
     steps:
 
       # This step checks out a copy of your repository.
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
           fetch-depth: 0
 
-      - uses: actions/setup-python@v6
+      - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
         with:
           python-version: 3.12
 
diff --git a/.github/workflows/docker_build.yml b/.github/workflows/docker_build.yml
index 319446ea..355c01ef 100644
--- a/.github/workflows/docker_build.yml
+++ b/.github/workflows/docker_build.yml
@@ -33,7 +33,7 @@ jobs:
     steps:
 
       # This step checks out a copy of your repository.
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
           fetch-depth: 0
 
@@ -45,11 +45,11 @@ jobs:
 
       # Setup docker build environment
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@bb05f3f5519dd87d3ba754cc423b652a5edd6d2c # v4.2.0
 
       # Login to GHCR (GitHub Container Registry) / Docker registry
       - name: Login to GHCR / Docker registry
-        uses: docker/login-action@v3
+        uses: docker/login-action@af1e73f918a031802d376d3c8bbc3fe56130a9b0 # v4.4.0
         with:
           registry: ghcr.io
           username: ${{ inputs.gh_username }}
@@ -57,7 +57,7 @@ jobs:
 
       # Build and push the docker image
       - name: Build and push image to GHCR / Docker registry
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@53b7df96c91f9c12dcc8a07bcb9ccacbed38856a # v7.3.0
         with:
           context: .
           file: ./docker/${{ inputs.docker_name }}/Dockerfile
diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index 90eea034..26e49ff9 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -23,11 +23,11 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
           fetch-depth: 0
 
-      - uses: actions/setup-python@v6
+      - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
         with:
           python-version: "3.12"
           cache: "pip"
@@ -41,7 +41,7 @@ jobs:
 
       - name: Upload Pages artifact
         if: github.event_name == 'push' && github.ref == 'refs/heads/main'
-        uses: actions/upload-pages-artifact@v5
+        uses: actions/upload-pages-artifact@fc324d3547104276b827a68afc52ff2a11cc49c9 # v5.0.0
         with:
           path: docs/_build/html
 
@@ -60,7 +60,7 @@ jobs:
       # can worsen a wedged Pages backend rather than help it recover.
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@v5
+        uses: actions/deploy-pages@cd2ce8fcbc39b97be8ca5fce6e763baed58fa128 # v5.0.0
         continue-on-error: true
 
       - name: Wait before retrying deploy
@@ -70,4 +70,4 @@ jobs:
       - name: Deploy to GitHub Pages (retry)
         id: deployment_retry
         if: steps.deployment.outcome == 'failure'
-        uses: actions/deploy-pages@v5
+        uses: actions/deploy-pages@cd2ce8fcbc39b97be8ca5fce6e763baed58fa128 # v5.0.0
diff --git a/.github/workflows/gen_release.yml b/.github/workflows/gen_release.yml
index 9db90d36..c2c1cdf9 100644
--- a/.github/workflows/gen_release.yml
+++ b/.github/workflows/gen_release.yml
@@ -28,11 +28,11 @@ jobs:
     if: startsWith(github.ref, 'refs/tags/')
     steps:
 
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
           fetch-depth: 0
 
-      - uses: actions/setup-python@v6
+      - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
         with:
           python-version: 3.12
 
diff --git a/.github/workflows/ruckus_ci.yml b/.github/workflows/ruckus_ci.yml
index 6ea7d02f..9eabbc5b 100644
--- a/.github/workflows/ruckus_ci.yml
+++ b/.github/workflows/ruckus_ci.yml
@@ -23,11 +23,11 @@ jobs:
     steps:
 
       # This step checks out a copy of your repository.
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
           fetch-depth: 0
 
-      - uses: actions/setup-python@v6
+      - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
         with:
           python-version: 3.12
 
diff --git a/docs/how-to/index.rst b/docs/how-to/index.rst
index dd315b8f..7355c895 100644
--- a/docs/how-to/index.rst
+++ b/docs/how-to/index.rst
@@ -13,6 +13,7 @@ setting up a project for the first time, see
    vitis_hls
    vitis_aie
    ghdl_simulation
+   xsim_rogue_cosim
    cadence_genus
    synopsys_dc
    firmware_release
diff --git a/docs/how-to/xsim_rogue_cosim.rst b/docs/how-to/xsim_rogue_cosim.rst
new file mode 100644
index 00000000..fb367993
--- /dev/null
+++ b/docs/how-to/xsim_rogue_cosim.rst
@@ -0,0 +1,160 @@
+How to Run the Rogue Co-Simulation in Vivado XSIM
+===================================================
+
+**Goal:** Run the surf Rogue TCP/SideBand co-simulation inside Vivado xsim,
+either interactively in the GUI or in batch mode.
+
+The co-simulation HDL and C sources live in the **surf** submodule under
+``axi/simlink/``; ruckus provides only the build and simulate orchestration
+described here. Any ``axi/simlink/...`` path below is relative to the surf
+submodule root, not ruckus.
+
+.. note::
+
+   This flow is GUI-interactive/local only and requires a licensed Vivado
+   install. It has no CI coverage — verification is manual against a local
+   Vivado + Rogue environment.
+
+Prerequisites
+-------------
+
+- ``libzmq >= 4.1.0`` and ``pkg-config`` on the build machine.
+- A Rogue-environment Python shell for the peer script (it imports
+  ``pyrogue`` / ``rogue``).
+- Vivado 2023.1 or newer — the floor enforced by ``project.tcl``'s
+  ``VersionCheck``. The latest *tested* Vivado release is tracked centrally by
+  ``CheckVivadoVersion`` (see :doc:`../reference/tcl_api`), which warns when the
+  active Vivado is newer; this page intentionally does not restate a version.
+- A surf version that provides the ``axi/simlink/xsim/`` DPI backend. Older
+  surf (legacy ``axi/simlink/sim`` + ``src`` VHPI layout) is VCS-only; use
+  ``make vcs`` there.
+
+Makefile Setup
+--------------
+
+Add the following to your project ``Makefile``:
+
+.. code-block:: makefile
+
+   include $(TOP_DIR)/submodules/ruckus/system_vivado.mk
+
+No additional variables are required. The co-sim hook is registered
+unconditionally by ``project.tcl`` and is a fast no-op for any project that
+doesn't contain a Rogue co-sim source.
+
+.. note::
+
+   ``make xsim`` and ``make gui`` automatically select the surf xsim DPI-C
+   backend (they export ``RUCKUS_SIM_BACKEND=xsim``), so having Synopsys VCS
+   sourced in the same shell alongside Vivado — common in a combined setup
+   script — no longer misroutes the flow to the VCS/VHPI backend. Switching
+   between this xsim flow and ``make vcs`` in the same build directory swaps
+   the backend automatically; no ``make clean`` is needed.
+
+Steps
+-----
+
+1. **Launch the GUI (or run batch xsim):**
+
+   .. code-block:: bash
+
+      make gui
+
+   For a headless batch run, name the demo testbench and let the simulation
+   free-run so the peer can connect and drive it:
+
+   .. code-block:: bash
+
+      make xsim VIVADO_PROJECT_SIM=RogueTcpStreamXsimDemoTb
+
+   The batch path elaborates ``VIVADO_PROJECT_SIM`` (default ``$(PROJECT)``,
+   the synthesis top), so it must name the demo testbench. The run length is
+   ``VIVADO_PROJECT_SIM_TIME``, whose default ``all`` free-runs until the
+   testbench calls ``$finish``/``$stop`` or is interrupted. The demo
+   testbenches have neither, so the run does not self-terminate — background
+   it, wait for the ``Listening on ports N & N+1`` print, start the peer, then
+   stop the simulation once the peer reports its result. To bound a run
+   instead, pass a time value, e.g. ``VIVADO_PROJECT_SIM_TIME="1000 ns"``.
+
+   Either target triggers ruckus's pre-compile hook, which detects any of
+   ``RogueTcpStream.vhd``, ``RogueTcpMemory.vhd``, or ``RogueSideBand.vhd`` in
+   the simulation sources, builds the combined ``RogueTcpDpi.so`` via ``xsc``,
+   and binds it with ``-sv_lib RogueTcpDpi`` — no manual build step.
+
+2. **Watch the console for the build and bind:**
+
+   Confirm the ``pkg-config``/``xsc`` build messages appear with no errors,
+   and, after ``launch_simulation``/``run``, the module's one-time
+   ``Listening on ports N & N+1`` print — that is the ready-for-peer signal.
+
+3. **Start the matching Rogue peer script:**
+
+   .. code-block:: bash
+
+      python3 prbsLoopbackDemo.py
+
+   Run this in a separate terminal, pointed at the same host/port the demo
+   testbench is listening on. Ruckus and the DPI hook are entirely automatic
+   up to this point; starting the peer and, if switching modules, selecting
+   the desired top-level testbench in the target's ``ruckus.tcl``
+   (``set_property top``) are the only manual steps.
+
+4. **Observe the waveform:**
+
+   Data movement between the DPI adapter and the peer confirms the round
+   trip.
+
+Key Variables
+-------------
+
+.. list-table::
+   :header-rows: 1
+   :widths: 22 15 63
+
+   * - Variable
+     - Default
+     - Description
+   * - ``VIVADO_PROJECT_SIM``
+     - ``$(PROJECT)``
+     - Top module for Vivado simulation. Set to the demo testbench (e.g.
+       ``RogueTcpStreamXsimDemoTb``) for a batch ``make xsim`` co-sim run.
+   * - ``VIVADO_PROJECT_SIM_TIME``
+     - ``all``
+     - Simulation run length. The default ``all`` free-runs until the
+       testbench calls ``$finish``/``$stop`` or is interrupted — required for
+       co-sim so the external peer can drive the testbench. Pass a time value
+       (e.g. ``1000 ns``) to bound the run instead.
+
+There is no co-sim-specific variable — the DPI hook auto-registers and
+auto-detects, so the existing simulation variables above are the only ones
+relevant to this flow.
+
+Troubleshooting
+----------------
+
+**"libzmq package was not found"**
+   .. code-block:: text
+
+      libzmq package was not found
+      Please make sure that you have libzmq installed
+      or have sourced the necessary rogue setup scripts
+
+   Install libzmq, or source the Rogue setup scripts that put it on
+   ``PKG_CONFIG_PATH``, then re-run ``make gui``/``make xsim``.
+
+**"no axi/simlink/xsim/ DPI co-simulation backend" at compile**
+   The surf version in your project predates the xsim DPI backend (legacy
+   ``axi/simlink/sim`` + ``src`` VHPI layout). The Vivado xsim co-sim requires
+   a surf that provides ``axi/simlink/xsim/``. Use ``make vcs`` for VCS
+   co-simulation with that surf version, or update surf.
+
+**"DPI function ... not found" at elaboration**
+   The ``.so`` is stale, ``-sv_lib`` was not bound, or the module-detection
+   guard did not fire because none of the three Rogue ``.vhd`` files are
+   present in the simulation sources. Confirm the module's source is in the
+   sim compile order and re-run the build.
+
+**Waveform runs with no data movement**
+   The peer script has not connected. Confirm it is running against the
+   correct host/port pair and that push/pull directions are not swapped —
+   see the port table in ``axi/simlink/README.md`` in surf.
diff --git a/docs/reference/makefile_reference.rst b/docs/reference/makefile_reference.rst
index 480f2c09..5f5b6e6b 100644
--- a/docs/reference/makefile_reference.rst
+++ b/docs/reference/makefile_reference.rst
@@ -29,7 +29,7 @@ Targets
    * - ``dcp``
      - Synthesis + DCP export (sets ``SYNTH_DCP=1``). Exports the post-synthesis checkpoint.
    * - ``gui``
-     - Open the Vivado project in GUI mode.
+     - Open the Vivado project in GUI mode. Automatically detects and builds the Rogue TCP/SideBand co-simulation DPI library when present; see :doc:`../how-to/xsim_rogue_cosim`.
    * - ``interactive``
      - Open Vivado in TCL interactive mode.
    * - ``sources``
@@ -46,10 +46,8 @@ Targets
      - Generate PyRogue tarball.
    * - ``yaml``
      - Generate CPSW YAML tarball.
-   * - ``wis``
-     - Generate ``init_wis.tcl`` for Windows Vivado initialisation.
    * - ``xsim``
-     - Run Vivado XSIM simulation.
+     - Run Vivado XSIM simulation. Automatically detects and builds the Rogue TCP/SideBand co-simulation DPI library when present; see :doc:`../how-to/xsim_rogue_cosim`.
    * - ``vcs``
      - Generate VCS simulation scripts.
    * - ``msim``
@@ -298,15 +296,22 @@ Simulation Variables
 
 .. envvar:: VIVADO_PROJECT_SIM
 
-   Top module name for Vivado simulation.
+   Top module name for Vivado simulation. For a batch Rogue co-sim, set this to
+   the demo testbench (e.g. ``RogueTcpStreamXsimDemoTb``); see
+   :doc:`../how-to/xsim_rogue_cosim`.
 
    :default: ``$(PROJECT)``
 
 .. envvar:: VIVADO_PROJECT_SIM_TIME
 
-   Default simulation run time.
+   Simulation run length. The default ``all`` free-runs until the testbench
+   calls ``$finish``/``$stop`` or is interrupted; a testbench with neither
+   (and a free-running clock) never self-terminates, so a batch ``make xsim``
+   must be stopped manually. Pass a time value (e.g. ``1000 ns``) to bound the
+   run. ``all`` is required for the Rogue co-sim so the external peer can drive
+   the testbench — see :doc:`../how-to/xsim_rogue_cosim`.
 
-   :default: ``1000 ns``
+   :default: ``all``
 
 .. envvar:: SIM_CARGS_VERILOG
 
diff --git a/system_vivado.mk b/system_vivado.mk
index 16c20708..27010ee2 100644
--- a/system_vivado.mk
+++ b/system_vivado.mk
@@ -106,11 +106,18 @@ export USE_SEGMENTED_CONFIG = 0
 endif
 
 # Vivado Simulation Variables
+# When left undefined, the sim_1 top is auto-picked-up from the project
+# (i.e. the "set_property top ... [get_filesets sim_1]" in the target's
+# ruckus.tcl). Define VIVADO_PROJECT_SIM only to override that top.
 ifndef VIVADO_PROJECT_SIM
-export VIVADO_PROJECT_SIM = $(PROJECT)
+export VIVADO_PROJECT_SIM =
 endif
+# Default sim run length. "all" runs until the testbench calls finish/stop or
+# is interrupted; a time value (e.g. "1000 ns") runs that long. Testbenches
+# without a finish/stop free-run under "all", so a batch "make xsim" there must
+# be stopped manually.
 ifndef VIVADO_PROJECT_SIM_TIME
-export VIVADO_PROJECT_SIM_TIME = 1000 ns
+export VIVADO_PROJECT_SIM_TIME = all
 endif
 
 # Synthesis Variables
@@ -400,12 +407,13 @@ yaml : $(SOURCE_DEPEND)
 	@cd $(OUT_DIR); tclsh $(RUCKUS_DIR)/vivado/cpsw.tcl
 
 ###############################################################
-#### Vivado WIS ###############################################
+#### Rogue Co-Simulation Backend ##############################
 ###############################################################
-.PHONY : wis
-wis : $(SOURCE_DEPEND)
-	$(call ACTION_HEADER,"Generating init_wis.tcl file for Windows OS")
-	@cd $(OUT_DIR); vivado -mode batch -source $(RUCKUS_DIR)/vivado/wis.tcl
+# Tell surf/axi/simlink/ruckus.tcl which Rogue co-sim backend the invoked
+# target wants. Target-specific + exported so it propagates to the shared
+# $(SOURCE_DEPEND) prerequisite recipe and into the vivado subprocess.
+xsim gui : export RUCKUS_SIM_BACKEND := xsim
+vcs      : export RUCKUS_SIM_BACKEND := vcs
 
 ###############################################################
 #### Vivado XSIM Simulation ###################################
diff --git a/vivado/gui.tcl b/vivado/gui.tcl
index 20384c87..5c7253da 100644
--- a/vivado/gui.tcl
+++ b/vivado/gui.tcl
@@ -18,6 +18,30 @@ source -quiet $::env(RUCKUS_DIR)/vivado/proc.tcl
 source -quiet $::env(RUCKUS_DIR)/vivado/properties.tcl
 source -quiet $::env(RUCKUS_DIR)/vivado/messages.tcl
 
+########################################################
+## Rogue co-sim GUI-path environment setup.
+## The interactive "Run Simulation" freezes the xsim subprocess environment
+## when launch_simulation starts -- which is earlier than the
+## xsim.compile.tcl.pre hook (vivado/run/pre/xsim.tcl) fires -- so setting
+## LD_PRELOAD from that hook is too late for the GUI. Set it here at GUI
+## startup, before the user launches a simulation, so the xsim subprocess
+## inherits it. Mirrors the batch simulate path in vivado/xsim.tcl and is
+## guarded on the Rogue xsim backend, so it is a no-op for non-Rogue projects.
+########################################################
+if { [RogueSimSources xsim] != "" } {
+   # GLIBCXX runtime fix: LD_PRELOAD a libstdc++ new enough for the co-sim's
+   # libzmq (see RoguePreloadLibStdCpp).
+   RoguePreloadLibStdCpp
+   # LD_LIBRARY_PATH parity so the interactively launched xsim subprocess
+   # finds RogueTcpDpi.so at runtime, mirroring vivado/xsim.tcl.
+   set simOutDir "${OUT_DIR}/${VIVADO_PROJECT}.sim/sim_1/behav/xsim"
+   if { [info exists ::env(LD_LIBRARY_PATH)] } {
+      set ::env(LD_LIBRARY_PATH) "${simOutDir}:$::env(LD_LIBRARY_PATH)"
+   } else {
+      set ::env(LD_LIBRARY_PATH) "${simOutDir}"
+   }
+}
+
 # Update the bitstream post script
 if { [isVersal] } {
    set_property STEPS.WRITE_DEVICE_IMAGE.TCL.POST ${RUCKUS_DIR}/vivado/run/post/gui_write.tcl [get_runs impl_1]
diff --git a/vivado/proc/sim_management.tcl b/vivado/proc/sim_management.tcl
index 6a85d287..e059e05e 100644
--- a/vivado/proc/sim_management.tcl
+++ b/vivado/proc/sim_management.tcl
@@ -95,3 +95,77 @@ proc MsimCompleteMessage {dirPath rogueSim} {
    puts "\t\$ ./sim_msim.sh"
    puts "********************************************************\n\n"
 }
+
+## Return the Rogue co-sim source files (RogueTcpStream/Memory/SideBand) in the
+## simulation fileset, or "" if none -- the shared detector for whether a
+## project uses the Rogue co-sim. Pass "vcs" to surface the get_files warning
+## when absent, or "xsim" to suppress it (the xsim pre-compile hook runs for
+## every xsim project, so a non-Rogue project must stay quiet). Called from
+## vivado/vcs.tcl, vivado/xsim.tcl, vivado/sources.tcl, vivado/run/pre/xsim.tcl.
+proc RogueSimSources {backend} {
+   set rogueFiles {RogueTcpStream.vhd RogueTcpMemory.vhd RogueSideBand.vhd}
+   if { ${backend} == "vcs" } {
+      return [get_files -compile_order sources -used_in simulation ${rogueFiles}]
+   } else {
+      return [get_files -quiet -compile_order sources -used_in simulation ${rogueFiles}]
+   }
+}
+
+## Verify libzmq >= 4.1.0 is available via pkg-config for the Rogue co-sim,
+## printing a clear diagnostic and exiting on failure. Called by the VCS flow
+## (vivado/vcs.tcl) and the xsim pre-compile hook (vivado/run/pre/xsim.tcl).
+proc RogueCheckLibZmq {} {
+   set err_ret [catch {exec pkg-config --exists {libzmq >= 4.1.0} --print-errors} libzmq]
+   if { ${libzmq} != "" } {
+      puts "\n\n\n\n\n********************************************************"
+      if { [string match "*Package libzmq was not found*" ${libzmq}] == 1 } {
+         puts "libzmq package was not found"
+         puts "Please make sure that you have libzmq installed"
+         puts "or have sourced the necessary rogue setup scripts"
+      } else {
+         puts ${libzmq}
+      }
+      puts "********************************************************\n\n\n\n\n"
+      exit -1
+   }
+}
+
+## LD_PRELOAD a libstdc++.so.6 new enough for the Rogue xsim co-sim's libzmq.
+## Vivado's loader wrapper prepends its bundled libstdc++ (e.g. GLIBCXX 3.4.25
+## in 2025.2) to LD_LIBRARY_PATH, which is too old for a libzmq built against a
+## newer GCC. LD_PRELOAD takes precedence over LD_LIBRARY_PATH, so it forces the
+## newer GLIBCXX regardless of the loader's path injection (a plain
+## LD_LIBRARY_PATH prepend would lose to the loader). Called from both the GUI
+## pre-compile hook (vivado/run/pre/xsim.tcl) and the batch simulate path
+## (vivado/xsim.tcl). Exits with an error if no suitable libstdc++ is found.
+proc RoguePreloadLibStdCpp {} {
+   set candidates {}
+   # 1) libstdc++ from the prefix that ships libzmq (most ABI-consistent)
+   if { [catch {exec pkg-config --variable=libdir libzmq} zmqLibDir] == 0 && ${zmqLibDir} != "" } {
+      lappend candidates ${zmqLibDir}/libstdc++.so.6
+   }
+   # 2) active gcc's libstdc++ (distro-layout agnostic)
+   if { [catch {exec gcc -print-file-name=libstdc++.so.6} gccLib] == 0 && [file exists ${gccLib}] } {
+      lappend candidates ${gccLib}
+   }
+   # 3) common system locations: RHEL/Rocky, then Debian/Ubuntu
+   lappend candidates /usr/lib64/libstdc++.so.6
+   lappend candidates /usr/lib/x86_64-linux-gnu/libstdc++.so.6
+   # Prepend the first existing candidate, preserving any existing LD_PRELOAD
+   foreach lib ${candidates} {
+      if { [file exists ${lib}] } {
+         if { [info exists ::env(LD_PRELOAD)] && $::env(LD_PRELOAD) != "" } {
+            set ::env(LD_PRELOAD) "${lib}:$::env(LD_PRELOAD)"
+         } else {
+            set ::env(LD_PRELOAD) ${lib}
+         }
+         return
+      }
+   }
+   # Fail loudly rather than let the sim die with an opaque GLIBCXX loader error
+   puts "\n\n\n\n\n********************************************************"
+   puts "ERROR: no libstdc++.so.6 with a modern GLIBCXX found for the Rogue xsim co-sim."
+   puts "Install a newer libstdc++ or source the rogue setup scripts, then retry."
+   puts "********************************************************\n\n\n\n\n"
+   exit -1
+}
diff --git a/vivado/project.tcl b/vivado/project.tcl
index 6491f0f3..da888acd 100644
--- a/vivado/project.tcl
+++ b/vivado/project.tcl
@@ -70,6 +70,13 @@ if { [VersionCompare 2014.2] <= 0 } {
    set_property xsim.unifast false        [get_filesets sim_1]
 
    set_property -name {xsim.compile.xvlog.more_options} -value {-d SIM_SPEED_UP} -objects [get_filesets sim_1]
+
+   # Register the DPI pre-compile hook unconditionally. The
+   # Rogue co-sim guard lives in the hook script itself, so this is a
+   # safe no-op for non-Rogue xsim projects. Registered here (not in
+   # xsim.tcl) because project.tcl is the only ruckus script sourced
+   # by both "make gui" and "make xsim" ahead of launch_simulation.
+   set_property -name {xsim.compile.tcl.pre} -value ${RUCKUS_DIR}/vivado/run/pre/xsim.tcl -objects [get_filesets sim_1]
 }
 
 # Enable general project multi-threading
diff --git a/vivado/run/pre/xsim.tcl b/vivado/run/pre/xsim.tcl
new file mode 100644
index 00000000..717c9303
--- /dev/null
+++ b/vivado/run/pre/xsim.tcl
@@ -0,0 +1,105 @@
+##############################################################################
+## This file is an addition to the 'SLAC Firmware Standard Library'.
+## It is subject to the license terms in the LICENSE.txt file found in the
+## top-level directory of this distribution and at:
+##    https://confluence.slac.stanford.edu/display/ppareg/LICENSE.html.
+## No part of 'SLAC Firmware Standard Library', including this file,
+## may be copied, modified, propagated, or distributed except according to
+## the terms contained in the LICENSE.txt file.
+##############################################################################
+
+## \file vivado/run/pre/xsim.tcl
+# \brief Vivado xsim pre-compile hook (xsim.compile.tcl.pre, registered
+# unconditionally by project.tcl). Detects the Rogue TCP/SideBand co-sim
+# sources, builds their DPI shared library via xsc, and binds it to xelab.
+# This script IS the guard: a non-Rogue xsim project is a fast no-op.
+# Fires for both "make gui" -> Run Simulation and "make xsim" (batch),
+# since project.tcl runs ahead of both launch paths.
+
+########################################################
+## Custom procs. Sourced before the guard (so the guard can use them) because
+## this compile hook may run in a fresh Tcl interpreter without proc.tcl.
+########################################################
+source -quiet $::env(RUCKUS_DIR)/vivado/proc/sim_management.tcl
+
+########################################################
+## Guard: only act when a Rogue co-sim source is present
+########################################################
+set rogueSimPath [RogueSimSources xsim]
+if { ${rogueSimPath} == "" } {
+   return
+}
+
+########################################################
+## Locate the surf axi/simlink/xsim/ build directory (../xsim/ sibling of the
+## detected RogueTcpStream.vhd, mirroring vcs.tcl's ../vcs/ resolution). Older
+## surf predates the xsim DPI backend (legacy axi/simlink/sim + src VHPI
+## layout) and has no xsim/ directory: the Vivado xsim Rogue co-sim cannot run
+## there. Fail fast with a clear pointer to "make vcs" instead of dying later
+## on a missing Makefile or an elaboration error.
+########################################################
+set simTbDirName [file dirname [lindex ${rogueSimPath} 0]]
+set simLinkDir ${simTbDirName}/../xsim/
+if { ![file exists ${simLinkDir}] } {
+   puts "*********************************************************************"
+   puts "ERROR: this surf has no axi/simlink/xsim/ DPI co-simulation backend."
+   puts "  Rogue co-sim source found: [file normalize [lindex ${rogueSimPath} 0]]"
+   puts "  The Vivado xsim (DPI-C) Rogue co-simulation requires a surf version"
+   puts "  that provides axi/simlink/xsim/. Use 'make vcs' for VCS co-simulation"
+   puts "  with this (older) surf version."
+   puts "*********************************************************************"
+   exit -1
+}
+
+########################################################
+## Version lock: the Rogue xsim DPI co-sim requires Vivado 2023.1+ (older xsc
+## link drivers cannot resolve the host multiarch crt/libs for RogueTcpDpi.so).
+## Sourced/checked only inside this Rogue-only path, so a non-Rogue xsim
+## project on an older Vivado is completely unaffected. Covers both
+## "make gui" -> Run Simulation and "make xsim", since this hook fires for both.
+########################################################
+source -quiet $::env(RUCKUS_DIR)/vivado/proc/project_management.tcl
+if { [VersionCheck 2023.1] < 0 } {
+   exit -1
+}
+
+########################################################
+## Check the zeromq library exists and its version
+########################################################
+RogueCheckLibZmq
+
+########################################################
+## Vivado's current working directory at compile-hook time
+## is the simulation run directory; stage the built .so there
+########################################################
+set simOutDir [pwd]
+
+########################################################
+## Build RogueTcpDpi.so via xsc (axi/simlink/xsim/Makefile)
+########################################################
+cd ${simLinkDir}
+exec make
+exec cp -f [glob -directory ${simLinkDir} *.so] ${simOutDir}/.
+exec make clean
+cd $::env(PROJ_DIR)
+
+########################################################
+## GLIBCXX runtime fix fallback: LD_PRELOAD a libstdc++ new enough for the
+## co-sim's libzmq (see RoguePreloadLibStdCpp). This compile-stage hook fires
+## after launch_simulation has already frozen the xsim subprocess environment,
+## so the effective fix is applied earlier: vivado/gui.tcl for the interactive
+## "Run Simulation" path and vivado/xsim.tcl for the batch path. This call is
+## kept as belt-and-suspenders for any flow that reaches the hook first.
+########################################################
+RoguePreloadLibStdCpp
+
+########################################################
+## The xelab "-sv_lib RogueTcpStream" binding is intentionally NOT set here.
+## Vivado builds elaborate.sh from xsim.elaborate.xelab.more_options at
+## launch_simulation start -- BEFORE this compile-stage (xsim.compile.tcl.pre)
+## hook runs -- so a set_property here never reaches the xelab command line.
+## The binding is registered at project-generation time in vivado/sources.tcl
+## (guarded on the xsim RogueTcpStream backend) so it persists into the .xpr
+## and is baked into the generated elaborate.sh. This hook only builds and
+## stages RogueTcpDpi.so, which must exist before elaboration.
+########################################################
diff --git a/vivado/sources.tcl b/vivado/sources.tcl
index 8c33a278..76c7b307 100644
--- a/vivado/sources.tcl
+++ b/vivado/sources.tcl
@@ -86,8 +86,9 @@ close ${out}
 set_property top ${PROJECT} [current_fileset]
 # set_property top "glbl"     [get_filesets sim_1]
 
-# If VIVADO_PROJECT_SIM variable exist, set as sim top
-if { [info exists ::env(VIVADO_PROJECT_SIM)] } {
+# If VIVADO_PROJECT_SIM is defined, use it to override the sim_1 top
+# (otherwise keep the top set by the target's ruckus.tcl)
+if { $::env(VIVADO_PROJECT_SIM) != "" } {
     set_property top ${VIVADO_PROJECT_SIM} [get_filesets sim_1]
 }
 
@@ -112,6 +113,28 @@ if { [get_files -of_objects [get_filesets {constrs_1}]] != "" } {
    set_property PATH_MODE AbsoluteFirst [get_files -of_objects [get_filesets {constrs_1}]]
 }
 
+# Bind the Rogue TCP/SideBand DPI shared library for Vivado xsim co-simulation.
+# This MUST run at project-generation time: after the simulation backend
+# sources are loaded (so the guard resolves) and before launch_simulation
+# generates elaborate.sh. Setting xsim.elaborate.xelab.more_options from the
+# xsim.compile.tcl.pre hook is too late -- elaborate.sh is already generated.
+# Guarded on the xsim Rogue backends, so it is a no-op for non-Rogue
+# projects and for the GHDL/VCS simulation backends.
+set rogueXsimSrc ""
+foreach rogueFile [RogueSimSources xsim] {
+   if { [string match {*/xsim/RogueTcpStream.vhd} ${rogueFile}] ||
+        [string match {*/xsim/RogueTcpMemory.vhd} ${rogueFile}] ||
+        [string match {*/xsim/RogueSideBand.vhd}  ${rogueFile}] } {
+      set rogueXsimSrc ${rogueFile}
+   }
+}
+if { ${rogueXsimSrc} != "" } {
+   set xelabOpt [get_property {xsim.elaborate.xelab.more_options} [get_filesets sim_1]]
+   if { [string first {-sv_lib RogueTcpDpi} ${xelabOpt}] == -1 } {
+      set_property -name {xsim.elaborate.xelab.more_options} -value "${xelabOpt} -sv_lib RogueTcpDpi" -objects [get_filesets sim_1]
+   }
+}
+
 # Check if we can upgrade IP cores
 if { $::IP_LIST != "" } {
    foreach ipPntr $::IP_LIST {
diff --git a/vivado/vcs.tcl b/vivado/vcs.tcl
index 4b90f0f4..647f54cf 100644
--- a/vivado/vcs.tcl
+++ b/vivado/vcs.tcl
@@ -255,26 +255,14 @@ export_simulation -force -absolute_path -simulator vcs -include ${include} -defi
 ## Build the simlink directory (required for softrware co-simulation)
 #####################################################################################################
 
-set rogueSimPath [get_files -compile_order sources -used_in simulation {RogueTcpStream.vhd RogueTcpMemory.vhd RogueSideBand.vhd}]
+set rogueSimPath [RogueSimSources vcs]
 if { ${rogueSimPath} != "" } {
 
    # Set the flag true
    set rogueSimEn true
 
    # Check the zeromq library exists and its version
-   set err_ret [catch {exec pkg-config --exists {libzmq >= 4.1.0} --print-errors} libzmq]
-   if { ${libzmq} != "" } {
-      puts "\n\n\n\n\n********************************************************"
-      if { [string match "*Package libzmq was not found*" ${libzmq}] == 1 } {
-         puts "libzmq package was not found"
-         puts "Please make sure that you have libzmq installed"
-         puts "or have sourced the necessary rogue setup scripts"
-      } else {
-         puts ${libzmq}
-      }
-      puts "********************************************************\n\n\n\n\n"
-      exit -1
-   }
+   RogueCheckLibZmq
 
    # Create the setup environment script: C-SHELL
    set envScript [open ${simTbOutDir}/setup_env.csh  w]
diff --git a/vivado/wis.tcl b/vivado/wis.tcl
deleted file mode 100644
index fa942823..00000000
--- a/vivado/wis.tcl
+++ /dev/null
@@ -1,96 +0,0 @@
-##############################################################################
-# This file is part of 'SLAC Firmware Standard Library'.
-# It is subject to the license terms in the LICENSE.txt file found in the
-# top-level directory of this distribution and at:
-#    https://confluence.slac.stanford.edu/display/ppareg/LICENSE.html.
-# No part of 'SLAC Firmware Standard Library', including this file,
-# may be copied, modified, propagated, or distributed except according to
-# the terms contained in the LICENSE.txt file.
-##############################################################################
-
-## \file vivado/wis.tcl
-# \brief Creates a tcl script that copies the current values of the KotoDpm project's
-# Linux OS environment variables. The purpose of the init.tcl output script is to
-# properly establish the environment variables within the Windows version of Vivado without the need
-# to first load Cygwin. This is useful because while using Vivado with Cygwin, Vivado runs roughly 2x slower.
-
-# Get variables and procedures
-source -quiet $::env(RUCKUS_DIR)/vivado/env_var.tcl
-source -quiet $::env(RUCKUS_DIR)/vivado/proc.tcl
-
-# Open the project
-open_project -quiet ${VIVADO_PROJECT}
-
-# create and open output file
-set fp [open init_wis.tcl w]
-
-########################################################
-## Declare a list of Linux environment variables to copy to script
-########################################################
-# SLAC Project Variables
-set     linuxVars "PRJ_PART"
-lappend linuxVars "PROJECT"
-lappend linuxVars "PRJ_VERSION"
-lappend linuxVars "PROJ_DIR"
-lappend linuxVars "TOP_DIR"
-lappend linuxVars "IMAGES_DIR"
-lappend linuxVars "OUT_DIR"
-lappend linuxVars "SYN_DIR"
-lappend linuxVars "IMPL_DIR"
-lappend linuxVars "VIVADO_DIR"
-lappend linuxVars "VIVADO_PROJECT"
-lappend linuxVars "VIVADO_VERSION"
-lappend linuxVars "RUCKUS_DIR"
-
-# SLAC Vivado SDK Variables
-lappend linuxVars "SDK_PRJ"
-lappend linuxVars "SDK_LIB"
-lappend linuxVars "SDK_ELF"
-
-# Partial Reconfiguration Variables
-lappend linuxVars "RECONFIG_CHECKPOINT"
-lappend linuxVars "RECONFIG_ENDPOINT"
-lappend linuxVars "RECONFIG_PBLOCK"
-
-# Set GIT variables
-lappend linuxVars "GIT_BYPASS"
-lappend linuxVars "GIT_STATUS"
-lappend linuxVars "GIT_HASH_LONG"
-lappend linuxVars "GIT_HASH_SHORT"
-lappend linuxVars "GIT_HASH_MSG"
-
-# Set Non-Environmental variables
-lappend linuxVars "vivado_cmd"
-
-########################################################
-## Copy list to tcl script
-########################################################
-# Create fp header
-puts $fp "## Script Generation Information"
-
-# Report Vivado version
-puts $fp "# Vivado version: [version -short]"
-
-# Report OS Information
-puts $fp "# Script generated by mother OS: $tcl_platform(os) $tcl_platform(osVersion)"
-
-# Report user information
-puts $fp "# Generated by user: $tcl_platform(user)"
-
-# Report general build string
-puts $fp "# Build String: $env(BUILD_STRING)"
-
-# write matching environment variables to file
-puts $fp " "
-puts $fp "# Set Environment Variables"
-for {set i 0} {$i < [llength $linuxVars]} {incr i} {
-    if {[info exists env([lindex $linuxVars $i])]} {
-            puts $fp "set env([lindex $linuxVars $i]) $env([lindex $linuxVars $i])"
-    }
-}
-
-# Close the file
-close $fp
-
-# Close the project
-close_project
diff --git a/vivado/xsim.tcl b/vivado/xsim.tcl
index 2d421920..a656fb83 100644
--- a/vivado/xsim.tcl
+++ b/vivado/xsim.tcl
@@ -48,6 +48,39 @@ if { [CheckPrjConfig sim_1] != true } {
 generate_target -quiet {simulation} [get_ips]
 export_ip_user_files -no_script
 
+########################################################
+## Rogue co-sim batch-path env parity. The guard
+## + xsc build + -sv_lib injection live in run/pre/xsim.tcl
+## (registered by project.tcl); this is belt-and-suspenders
+## only for the batch xsim subprocess -- no duplicate build.
+########################################################
+set rogueSimPath [RogueSimSources xsim]
+if { ${rogueSimPath} != "" } {
+
+   # Version lock: the Rogue xsim DPI co-sim requires Vivado 2023.1+ (see
+   # vivado/run/pre/xsim.tcl). Fail fast on the "make xsim" batch path, before
+   # launch_simulation. Only reached when the co-sim is used, so a non-Rogue
+   # xsim project on an older Vivado is unaffected.
+   if { [VersionCheck 2023.1] < 0 } {
+      exit -1
+   }
+
+   # GLIBCXX runtime fix for the batch xsim subprocess: LD_PRELOAD a libstdc++
+   # new enough for the co-sim's libzmq (see RoguePreloadLibStdCpp). The GUI
+   # path applies the same fix from vivado/run/pre/xsim.tcl.
+   RoguePreloadLibStdCpp
+
+   # LD_LIBRARY_PATH parity so a script-launched xsim subprocess
+   # finds libRogueTcpStream.so at runtime, mirroring vcs.tcl's
+   # setup_env LD_LIBRARY_PATH prepend
+   set simOutDir "${OUT_DIR}/${VIVADO_PROJECT}.sim/sim_1/behav/xsim"
+   if { [info exists ::env(LD_LIBRARY_PATH)] } {
+      set ::env(LD_LIBRARY_PATH) "${simOutDir}:$::env(LD_LIBRARY_PATH)"
+   } else {
+      set ::env(LD_LIBRARY_PATH) "${simOutDir}"
+   }
+}
+
 ########################################################
 ## Simulate Process
 ########################################################
@@ -55,7 +88,11 @@ set sim_rc [catch {
 
    # Set sim properties
    set_property target_simulator XSim [current_project]
-   set_property top ${VIVADO_PROJECT_SIM} [get_filesets sim_1]
+   # Only override the sim_1 top when VIVADO_PROJECT_SIM is explicitly defined;
+   # otherwise keep the top auto-picked-up from the target's ruckus.tcl
+   if { ${VIVADO_PROJECT_SIM} != "" } {
+      set_property top ${VIVADO_PROJECT_SIM} [get_filesets sim_1]
+   }
    set_property top_lib xil_defaultlib [get_filesets sim_1]
 
    # Launch the xsim