diff --git a/litex/build/openfpga/blinky.py b/litex/build/openfpga/blinky.py
index 4dd2d547a..cfa504680 100755
--- a/litex/build/openfpga/blinky.py
+++ b/litex/build/openfpga/blinky.py
@@ -34,7 +34,7 @@ clk      = platform.request("clk")
 led      = platform.request("led")
 module   = Module()
 module.clock_domains.cd_sys = ClockDomain("sys")
-module.cd_sys.clk.eq(clk)
+module.comb += module.cd_sys.clk.eq(clk)
 counter  = Signal(26)
 module.comb += led.eq(counter[25])
 module.sync += counter.eq(counter + 1)
diff --git a/litex/build/osfpga/__init__.py b/litex/build/osfpga/__init__.py
new file mode 100644
index 000000000..9b874d960
--- /dev/null
+++ b/litex/build/osfpga/__init__.py
@@ -0,0 +1 @@
+from litex.build.osfpga.platform import OSFPGAPlatform
diff --git a/litex/build/osfpga/blinky.py b/litex/build/osfpga/blinky.py
new file mode 100755
index 000000000..7c1054e0b
--- /dev/null
+++ b/litex/build/osfpga/blinky.py
@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+
+#
+# This file is part of LiteX.
+#
+# Copyright (c) 2022 Florent Kermarrec <florent@enjoy-digital.fr>
+# SPDX-License-Identifier: BSD-2-Clause
+
+import os
+
+from migen import *
+
+from litex.build.generic_platform import Pins
+from litex.build.osfpga import OSFPGAPlatform
+
+# Minimal Platform ---------------------------------------------------------------------------------
+
+_io = [
+    ("clk", 0, Pins(1)),
+    ("led", 0, Pins(1))
+]
+
+class Platform(OSFPGAPlatform):
+    def __init__(self):
+        OSFPGAPlatform.__init__(self, device=None, io=_io) # FIXME: Add device support.
+
+# Minimal Design -----------------------------------------------------------------------------------
+
+platform = Platform()
+clk      = platform.request("clk")
+led      = platform.request("led")
+module   = Module()
+module.clock_domains.cd_sys = ClockDomain("sys")
+module.comb += module.cd_sys.clk.eq(clk)
+counter  = Signal(26)
+module.comb += led.eq(counter[25])
+module.sync += counter.eq(counter + 1)
+
+# Build --------------------------------------------------------------------------------------------
+
+platform.build(module, build_name="blinky", run=True)
diff --git a/litex/build/osfpga/common.py b/litex/build/osfpga/common.py
new file mode 100644
index 000000000..45ff7e469
--- /dev/null
+++ b/litex/build/osfpga/common.py
@@ -0,0 +1,14 @@
+#
+# This file is part of LiteX.
+#
+# Copyright (c) 2022 Florent Kermarrec <florent@enjoy-digital.fr>
+# SPDX-License-Identifier: BSD-2-Clause
+
+from migen.fhdl.module import Module
+from migen.genlib.resetsync import AsyncResetSynchronizer
+
+from litex.build.io import *
+
+# OS-FPGA Special Overrides --------------------------------------------------------------------------
+
+osfpga_special_overrides = {}
diff --git a/litex/build/osfpga/foedag.py b/litex/build/osfpga/foedag.py
new file mode 100644
index 000000000..a84a718d2
--- /dev/null
+++ b/litex/build/osfpga/foedag.py
@@ -0,0 +1,137 @@
+#
+# This file is part of LiteX.
+#
+# Copyright (c) 2022 Florent Kermarrec <florent@enjoy-digital.fr>
+# SPDX-License-Identifier: BSD-2-Clause
+
+import os
+import sys
+import math
+import subprocess
+from shutil import which, copyfile
+
+from migen.fhdl.structure import _Fragment
+
+from litex.build.generic_platform import *
+from litex.build import tools
+
+# Timing Constraints (.sdc) ------------------------------------------------------------------------
+
+def _build_sdc(clocks, vns, build_name):
+    sdc = []
+    for clk, period in sorted(clocks.items(), key=lambda x: x[0].duid):
+        sdc.append(f"create_clock -name {vns.get_name(clk)} -period {str(period)} [get_ports {{{vns.get_name(clk)}}}]")
+    with open(f"{build_name}.sdc", "w") as f:
+        f.write("\n".join(sdc))
+
+# Script -------------------------------------------------------------------------------------------
+
+def _build_tcl(name, device, files, build_name):
+    tcl = []
+
+    # Create Design.
+    tcl.append(f"create_design {build_name}")
+
+    # Set Device.
+    # TODO (Use Macro for now).
+    tcl.append("set_macro P1=10  P2=20")
+
+    # Add Include Path.
+    # TODO.
+
+    # Add Sources.
+    for f, typ, lib in files:
+        tcl.append(f"add_design_file {f}")
+
+    # Set Top Module.
+    tcl.append(f"set_top_module {build_name}")
+
+    # Add Timings Constraints.
+    tcl.append(f"add_constraint_file {build_name}.sdc")
+
+    # Run.
+    tcl.append("synth")
+    tcl.append("packing")
+    tcl.append("place")
+    tcl.append("route")
+    tcl.append("sta")
+    tcl.append("power")
+    tcl.append("bitstream")
+
+    # Generate .tcl.
+    with open("build.tcl", "w") as f:
+        f.write("\n".join(tcl))
+
+# FOEDAGToolchain -----------------------------------------------------------------------------------
+
+class FOEDAGToolchain:
+    attr_translate = {}
+
+    def __init__(self):
+        self.clocks  = dict()
+
+    def build(self, platform, fragment,
+        build_dir  = "build",
+        build_name = "top",
+        run        = True,
+        **kwargs):
+
+        # Create build directory.
+        cwd = os.getcwd()
+        os.makedirs(build_dir, exist_ok=True)
+        os.chdir(build_dir)
+
+        # Finalize design
+        if not isinstance(fragment, _Fragment):
+            fragment = fragment.get_fragment()
+        platform.finalize(fragment)
+
+        # Generate verilog
+        v_output = platform.get_verilog(fragment, name=build_name, **kwargs)
+        named_sc, named_pc = platform.resolve_signals(v_output.ns)
+        v_file = build_name + ".v"
+        v_output.write(v_file)
+        platform.add_source(v_file)
+
+        # Generate constraints file.
+        # IOs.
+        # TODO.
+
+        # Timings (.sdc)
+        _build_sdc(
+            clocks     = self.clocks,
+            vns        = v_output.ns,
+            build_name = build_name,
+        )
+
+        # Generate build script (.tcl)
+        script = _build_tcl(
+            name       = platform.devicename,
+            device     = platform.device,
+            files      = platform.sources,
+            build_name = build_name,
+        )
+
+        # Run
+        if run:
+            foedag_sh = "foedag"
+            if which(foedag_sh) is None:
+                msg = "Unable to find FOEDAG toolchain, please:\n"
+                msg += "- Add FOEDAG toolchain to your $PATH."
+                raise OSError(msg)
+
+            if subprocess.call([foedag_sh, "--batch", "--script", "build.tcl"]) != 0:
+                raise OSError("Error occured during FOEDAG's script execution.")
+
+        os.chdir(cwd)
+
+        return v_output.ns
+
+    def add_period_constraint(self, platform, clk, period):
+        clk.attr.add("keep")
+        period = math.floor(period*1e3)/1e3 # round to lowest picosecond
+        if clk in self.clocks:
+            if period != self.clocks[clk]:
+                raise ValueError("Clock already constrained to {:.2f}ns, new constraint to {:.2f}ns"
+                    .format(self.clocks[clk], period))
+        self.clocks[clk] = period
diff --git a/litex/build/osfpga/platform.py b/litex/build/osfpga/platform.py
new file mode 100644
index 000000000..6412bd1b8
--- /dev/null
+++ b/litex/build/osfpga/platform.py
@@ -0,0 +1,38 @@
+#
+# This file is part of LiteX.
+#
+# Copyright (c) 2022 Florent Kermarrec <florent@enjoy-digital.fr>
+# SPDX-License-Identifier: BSD-2-Clause
+
+import os
+
+from litex.build.generic_platform import GenericPlatform
+from litex.build.osfpga import common, foedag
+
+# OSFPGAPlatform -----------------------------------------------------------------------------------
+
+class OSFPGAPlatform(GenericPlatform):
+    bitstream_ext = ".bin"
+
+    def __init__(self, device, *args, toolchain="foedag", devicename=None, **kwargs):
+        GenericPlatform.__init__(self, device, *args, **kwargs)
+        self.devicename = devicename
+        if toolchain == "foedag":
+            self.toolchain = foedag.FOEDAGToolchain()
+        else:
+            raise ValueError(f"Unknown toolchain {toolchain}")
+
+    def get_verilog(self, *args, special_overrides=dict(), **kwargs):
+        so = dict(common.osfpga_special_overrides)
+        so.update(special_overrides)
+        return GenericPlatform.get_verilog(self, *args,
+            special_overrides = so,
+            attr_translate    = self.toolchain.attr_translate,
+            **kwargs)
+
+    def build(self, *args, **kwargs):
+        return self.toolchain.build(self, *args, **kwargs)
+
+    def add_period_constraint(self, clk, period):
+        if clk is None: return
+        self.toolchain.add_period_constraint(self, clk, period)