diff --git a/src/main/scala/example/ConfigMixins.scala b/src/main/scala/example/ConfigMixins.scala
new file mode 100644
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+++ b/src/main/scala/example/ConfigMixins.scala
@@ -0,0 +1,170 @@
+package example
+
+import chisel3._
+import freechips.rocketchip.config.{Parameters, Config}
+import freechips.rocketchip.subsystem.{WithRoccExample, WithNMemoryChannels, WithNBigCores, WithRV32}
+import freechips.rocketchip.diplomacy.{LazyModule, ValName}
+import freechips.rocketchip.devices.tilelink.BootROMParams
+import freechips.rocketchip.tile.XLen
+import testchipip._
+import sifive.blocks.devices.gpio._
+
+/**
+ * TODO: Why do we need this?
+ */
+object ConfigValName {
+  implicit val valName = ValName("TestHarness")
+}
+import ConfigValName._
+
+// -----------------------
+// Common Parameter Mixins
+// -----------------------
+
+/**
+ * Class to specify where the BootRom file is (from `rebar` top)
+ */
+class WithBootROM extends Config((site, here, up) => {
+  case BootROMParams => BootROMParams(
+    contentFileName = s"./bootrom/bootrom.rv${site(XLen)}.img")
+})
+
+/**
+ * Class to add in GPIO
+ */
+class WithGPIO extends Config((site, here, up) => {
+  case PeripheryGPIOKey => List(
+    GPIOParams(address = 0x10012000, width = 4, includeIOF = false))
+})
+
+// ----------------------------------------
+// Rocket Top Level System Parameter Mixins
+// ----------------------------------------
+
+/**
+ * Class to specify a "plain" top level rocket-chip system
+ */
+class WithNormalRocketTop extends Config((site, here, up) => {
+  case BuildRocketTop => (clock: Clock, reset: Bool, p: Parameters) => {
+    Module(LazyModule(new RocketTop()(p)).module)
+  }
+})
+
+/**
+ * Class to specify a top level rocket-chip system with PWM
+ */
+class WithPWMRocketTop extends Config((site, here, up) => {
+  case BuildRocketTop => (clock: Clock, reset: Bool, p: Parameters) =>
+    Module(LazyModule(new RocketTopWithPWMTL()(p)).module)
+})
+
+/**
+ * Class to specify a top level rocket-chip system with a PWM AXI4
+ */
+class WithPWMAXI4RocketTop extends Config((site, here, up) => {
+  case BuildRocketTop => (clock: Clock, reset: Bool, p: Parameters) =>
+    Module(LazyModule(new RocketTopWithPWMAXI4()(p)).module)
+})
+
+/**
+ * Class to specify a top level rocket-chip system with a block device
+ */
+class WithBlockDeviceModelRocketTop extends Config((site, here, up) => {
+  case BuildRocketTop => (clock: Clock, reset: Bool, p: Parameters) => {
+    val top = Module(LazyModule(new RocketTopWithBlockDevice()(p)).module)
+    top.connectBlockDeviceModel()
+    top
+  }
+})
+
+/**
+ * Class to specify a top level rocket-chip system with a simulator block device
+ */
+class WithSimBlockDeviceRocketTop extends Config((site, here, up) => {
+  case BuildRocketTop => (clock: Clock, reset: Bool, p: Parameters) => {
+    val top = Module(LazyModule(new RocketTopWithBlockDevice()(p)).module)
+    top.connectSimBlockDevice(clock, reset)
+    top
+  }
+})
+
+/**
+ * Class to specify a top level rocket-chip system with GPIO
+ */
+class WithGPIORocketTop extends Config((site, here, up) => {
+  case BuildRocketTop => (clock: Clock, reset: Bool, p: Parameters) => {
+    val top = Module(LazyModule(new RocketTopWithGPIO()(p)).module)
+    for (gpio <- top.gpio) {
+      for (pin <- gpio.pins) {
+        pin.i.ival := false.B
+      }
+    }
+    top
+  }
+})
+
+// --------------------------------------
+// BOOM Top Level System Parameter Mixins
+// --------------------------------------
+
+/**
+ * Class to specify a "plain" top level BOOM system
+ */
+class WithNormalBoomTop extends Config((site, here, up) => {
+  case BuildBoomTop => (clock: Clock, reset: Bool, p: Parameters) => {
+    Module(LazyModule(new BoomTop()(p)).module)
+  }
+})
+
+/**
+ * Class to specify a top level BOOM system with PWM
+ */
+class WithPWMBoomTop extends Config((site, here, up) => {
+  case BuildBoomTop => (clock: Clock, reset: Bool, p: Parameters) =>
+    Module(LazyModule(new BoomTopWithPWMTL()(p)).module)
+})
+
+/**
+ * Class to specify a top level BOOM system with a PWM AXI4
+ */
+class WithPWMAXI4BoomTop extends Config((site, here, up) => {
+  case BuildBoomTop => (clock: Clock, reset: Bool, p: Parameters) =>
+    Module(LazyModule(new BoomTopWithPWMAXI4()(p)).module)
+})
+
+/**
+ * Class to specify a top level BOOM system with a block device
+ */
+class WithBlockDeviceModelBoomTop extends Config((site, here, up) => {
+  case BuildBoomTop => (clock: Clock, reset: Bool, p: Parameters) => {
+    val top = Module(LazyModule(new BoomTopWithBlockDevice()(p)).module)
+    top.connectBlockDeviceModel()
+    top
+  }
+})
+
+/**
+ * Class to specify a top level BOOM system with a simulator block device
+ */
+class WithSimBlockDeviceBoomTop extends Config((site, here, up) => {
+  case BuildBoomTop => (clock: Clock, reset: Bool, p: Parameters) => {
+    val top = Module(LazyModule(new BoomTopWithBlockDevice()(p)).module)
+    top.connectSimBlockDevice(clock, reset)
+    top
+  }
+})
+
+/**
+ * Class to specify a top level BOOM system with GPIO
+ */
+class WithGPIOBoomTop extends Config((site, here, up) => {
+  case BuildBoomTop => (clock: Clock, reset: Bool, p: Parameters) => {
+    val top = Module(LazyModule(new BoomTopWithGPIO()(p)).module)
+    for (gpio <- top.gpio) {
+      for (pin <- gpio.pins) {
+        pin.i.ival := false.B
+      }
+    }
+    top
+  }
+})