diff --git a/junctions/src/main/scala/atos.scala b/junctions/src/main/scala/atos.scala
new file mode 100644
index 00000000..ed2160a8
--- /dev/null
+++ b/junctions/src/main/scala/atos.scala
@@ -0,0 +1,286 @@
+package junctions
+
+import Chisel._
+import scala.math.max
+import cde.{Parameters, Field}
+
+trait HasAtosParameters extends HasNastiParameters {
+  // round up to a multiple of 32
+  def roundup(n: Int) = 32 * ((n - 1) / 32 + 1)
+
+  val atosUnionBits = max(nastiXDataBits + nastiWStrobeBits + 1,
+    nastiXIdBits + nastiXBurstBits +
+    nastiXSizeBits + nastiXLenBits + nastiXAddrBits)
+  val atosIdBits = nastiXIdBits
+  val atosTypBits = 2
+  val atosRespBits = nastiXRespBits
+  val atosDataBits = nastiXDataBits
+
+  val atosLenOffset = nastiXAddrBits
+  val atosSizeOffset = atosLenOffset + nastiXLenBits
+  val atosBurstOffset = atosSizeOffset + nastiXSizeBits
+  val atosIdOffset = atosBurstOffset + nastiXBurstBits
+  val atosStrobeOffset = nastiXDataBits
+  val atosLastOffset = atosStrobeOffset + nastiWStrobeBits
+
+  val atosRequestBits = roundup(atosTypBits + atosUnionBits)
+  val atosResponseBits = roundup(atosTypBits + atosIdBits + atosRespBits + atosDataBits + 1)
+  val atosRequestBytes = atosRequestBits / 8
+  val atosResponseBytes = atosResponseBits / 8
+  val atosRequestWords = atosRequestBytes / 4
+  val atosResponseWords = atosResponseBytes / 4
+}
+
+abstract class AtosModule(implicit val p: Parameters)
+  extends Module with HasAtosParameters
+abstract class AtosBundle(implicit val p: Parameters)
+  extends ParameterizedBundle()(p) with HasAtosParameters
+
+object AtosRequest {
+  def arType = UInt("b00")
+  def awType = UInt("b01")
+  def wType  = UInt("b10")
+
+  def apply(typ: UInt, union: UInt)(implicit p: Parameters): AtosRequest = {
+    val areq = Wire(new AtosRequest)
+    areq.typ := typ
+    areq.union := union
+    areq
+  }
+
+  def apply(ar: NastiReadAddressChannel)(implicit p: Parameters): AtosRequest =
+    apply(arType, Cat(ar.id, ar.burst, ar.size, ar.len, ar.addr))
+
+  def apply(aw: NastiWriteAddressChannel)(implicit p: Parameters): AtosRequest =
+    apply(awType, Cat(aw.id, aw.burst, aw.size, aw.len, aw.addr))
+
+  def apply(w: NastiWriteDataChannel)(implicit p: Parameters): AtosRequest =
+    apply(wType, Cat(w.last, w.strb, w.data))
+}
+
+class AtosRequest(implicit p: Parameters)
+    extends AtosBundle()(p) with Serializable {
+  val typ = UInt(width = atosTypBits)
+  val union = UInt(width = atosUnionBits)
+
+  def id(dummy: Int = 0) =
+    union(atosIdOffset + nastiXIdBits - 1, atosIdOffset)
+
+  def burst(dummy: Int = 0) =
+    union(atosIdOffset - 1, atosBurstOffset)
+
+  def size(dummy: Int = 0) =
+    union(atosBurstOffset - 1, atosSizeOffset)
+
+  def len(dummy: Int = 0) =
+    union(atosSizeOffset - 1, atosLenOffset)
+
+  def addr(dummy: Int = 0) =
+    union(atosLenOffset - 1, 0)
+
+  def data(dummy: Int = 0) =
+    union(nastiXDataBits - 1, 0)
+
+  def strb(dummy: Int = 0) =
+    union(atosLastOffset - 1, atosStrobeOffset)
+
+  def last(dummy: Int = 0) =
+    union(atosLastOffset)
+
+  def has_addr(dummy: Int = 0) =
+    typ === AtosRequest.arType || typ === AtosRequest.awType
+
+  def has_data(dummy: Int = 0) =
+    typ === AtosRequest.wType
+
+  def is_last(dummy: Int = 0) =
+    typ === AtosRequest.arType || (typ === AtosRequest.wType && last())
+
+  def nbytes: Int = atosRequestBytes
+}
+
+object AtosResponse {
+  def rType = UInt("b00")
+  def bType = UInt("b01")
+
+  def apply(typ: UInt, id: UInt, resp: UInt, data: UInt, last: Bool)
+      (implicit p: Parameters): AtosResponse = {
+    val aresp = Wire(new AtosResponse)
+    aresp.typ := typ
+    aresp.id := id
+    aresp.resp := resp
+    aresp.data := data
+    aresp.last := last
+    aresp
+  }
+
+  def apply(r: NastiReadDataChannel)(implicit p: Parameters): AtosResponse =
+    apply(rType, r.id, r.resp, r.data, r.last)
+
+  def apply(b: NastiWriteResponseChannel)(implicit p: Parameters): AtosResponse =
+    apply(bType, b.id, b.resp, UInt(0), Bool(false))
+}
+
+class AtosResponse(implicit p: Parameters)
+    extends AtosBundle()(p) with Serializable {
+  val typ = UInt(width = atosTypBits)
+  val id = UInt(width = atosIdBits)
+  val resp = UInt(width = atosRespBits)
+  val last = Bool()
+  val data = UInt(width = atosDataBits)
+
+  def has_data(dummy: Int = 0) = typ === AtosResponse.rType
+
+  def is_last(dummy: Int = 0) = !has_data() || last
+
+  def nbytes: Int = atosResponseBytes
+}
+
+class AtosIO(implicit p: Parameters) extends AtosBundle()(p) {
+  val req = Decoupled(new AtosRequest)
+  val resp = Decoupled(new AtosResponse).flip
+}
+
+class AtosRequestEncoder(implicit p: Parameters) extends AtosModule()(p) {
+  val io = new Bundle {
+    val ar = Decoupled(new NastiReadAddressChannel).flip
+    val aw = Decoupled(new NastiWriteAddressChannel).flip
+    val w  = Decoupled(new NastiWriteDataChannel).flip
+    val req = Decoupled(new AtosRequest)
+  }
+
+  val writing = Reg(init = Bool(false))
+
+  io.ar.ready := !writing && io.req.ready
+  io.aw.ready := !writing && !io.ar.valid && io.req.ready
+  io.w.ready  := writing && io.req.ready
+
+  io.req.valid := Mux(writing, io.w.valid, io.ar.valid || io.aw.valid)
+  io.req.bits := Mux(writing, AtosRequest(io.w.bits),
+    Mux(io.ar.valid, AtosRequest(io.ar.bits), AtosRequest(io.aw.bits)))
+
+  when (io.aw.fire()) { writing := Bool(true) }
+  when (io.w.fire() && io.w.bits.last) { writing := Bool(false) }
+}
+
+class AtosResponseDecoder(implicit p: Parameters) extends AtosModule()(p) {
+  val io = new Bundle {
+    val resp = Decoupled(new AtosResponse).flip
+    val b = Decoupled(new NastiWriteResponseChannel)
+    val r = Decoupled(new NastiReadDataChannel)
+  }
+
+  val is_b = io.resp.bits.typ === AtosResponse.bType
+  val is_r = io.resp.bits.typ === AtosResponse.rType
+
+  io.b.valid := io.resp.valid && is_b
+  io.b.bits := NastiWriteResponseChannel(
+    id = io.resp.bits.id,
+    resp = io.resp.bits.resp)
+
+  io.r.valid := io.resp.valid && is_r
+  io.r.bits := NastiReadDataChannel(
+    id = io.resp.bits.id,
+    data = io.resp.bits.data,
+    last = io.resp.bits.last,
+    resp = io.resp.bits.resp)
+
+  io.resp.ready := (is_b && io.b.ready) || (is_r && io.r.ready)
+}
+
+class AtosClientConverter(implicit p: Parameters) extends AtosModule()(p) {
+  val io = new Bundle {
+    val nasti = (new NastiIO).flip
+    val atos = new AtosIO
+  }
+
+  val req_enc = Module(new AtosRequestEncoder)
+  req_enc.io.ar <> io.nasti.ar
+  req_enc.io.aw <> io.nasti.aw
+  req_enc.io.w  <> io.nasti.w
+  io.atos.req <> req_enc.io.req
+
+  val resp_dec = Module(new AtosResponseDecoder)
+  resp_dec.io.resp <> io.atos.resp
+  io.nasti.b <> resp_dec.io.b
+  io.nasti.r <> resp_dec.io.r
+}
+
+class AtosRequestDecoder(implicit p: Parameters) extends AtosModule()(p) {
+  val io = new Bundle {
+    val req = Decoupled(new AtosRequest).flip
+    val ar = Decoupled(new NastiReadAddressChannel)
+    val aw = Decoupled(new NastiWriteAddressChannel)
+    val w  = Decoupled(new NastiWriteDataChannel)
+  }
+
+  val is_ar = io.req.bits.typ === AtosRequest.arType
+  val is_aw = io.req.bits.typ === AtosRequest.awType
+  val is_w  = io.req.bits.typ === AtosRequest.wType
+
+  io.ar.valid := io.req.valid && is_ar
+  io.ar.bits := NastiReadAddressChannel(
+    id = io.req.bits.id(),
+    addr = io.req.bits.addr(),
+    size = io.req.bits.size(),
+    len = io.req.bits.len(),
+    burst = io.req.bits.burst())
+
+  io.aw.valid := io.req.valid && is_aw
+  io.aw.bits := NastiWriteAddressChannel(
+    id = io.req.bits.id(),
+    addr = io.req.bits.addr(),
+    size = io.req.bits.size(),
+    len = io.req.bits.len(),
+    burst = io.req.bits.burst())
+
+  io.w.valid := io.req.valid && is_w
+  io.w.bits := NastiWriteDataChannel(
+    data = io.req.bits.data(),
+    strb = io.req.bits.strb(),
+    last = io.req.bits.last())
+
+  io.req.ready := (io.ar.ready && is_ar) ||
+                  (io.aw.ready && is_aw) ||
+                  (io.w.ready  && is_w)
+}
+
+class AtosResponseEncoder(implicit p: Parameters) extends AtosModule()(p) {
+  val io = new Bundle {
+    val b = Decoupled(new NastiWriteResponseChannel).flip
+    val r = Decoupled(new NastiReadDataChannel).flip
+    val resp = Decoupled(new AtosResponse)
+  }
+
+  val locked = Reg(init = Bool(false))
+
+  io.resp.valid := (io.b.valid && !locked) || io.r.valid
+  io.resp.bits := Mux(io.r.valid,
+    AtosResponse(io.r.bits), AtosResponse(io.b.bits))
+
+  io.b.ready := !locked && !io.r.valid && io.resp.ready
+  io.r.ready := io.resp.ready
+
+  when (io.r.fire() && !io.r.bits.last) { locked := Bool(true) }
+  when (io.r.fire() && io.r.bits.last) { locked := Bool(false) }
+}
+
+class AtosManagerConverter(implicit p: Parameters) extends AtosModule()(p) {
+  val io = new Bundle {
+    val atos = (new AtosIO).flip
+    val nasti = new NastiIO
+  }
+
+  val req_dec = Module(new AtosRequestDecoder)
+  val resp_enc = Module(new AtosResponseEncoder)
+
+  req_dec.io.req <> io.atos.req
+  io.atos.resp <> resp_enc.io.resp
+
+  io.nasti.ar <> req_dec.io.ar
+  io.nasti.aw <> req_dec.io.aw
+  io.nasti.w  <> req_dec.io.w
+
+  resp_enc.io.b <> io.nasti.b
+  resp_enc.io.r <> io.nasti.r
+}
diff --git a/junctions/src/main/scala/stream.scala b/junctions/src/main/scala/stream.scala
index a0380eb5..2b577272 100644
--- a/junctions/src/main/scala/stream.scala
+++ b/junctions/src/main/scala/stream.scala
@@ -87,3 +87,96 @@ class NastiIOStreamIOConverter(w: Int)(implicit p: Parameters) extends Module {
 
   when (io.nasti.b.fire()) { write_resp := Bool(false) }
 }
+
+class StreamNarrower(win: Int, wout: Int) extends Module {
+  require(win > wout, "Stream narrower input width must be larger than input width")
+  require(win % wout == 0, "Stream narrower input width must be multiple of output width")
+
+  val io = new Bundle {
+    val in = Decoupled(new StreamChannel(win)).flip
+    val out = Decoupled(new StreamChannel(wout))
+  }
+
+  val n_pieces = win / wout
+  val buffer = Reg(Bits(width = win))
+  val (piece_idx, pkt_done) = Counter(io.out.fire(), n_pieces)
+  val pieces = Vec.tabulate(n_pieces) { i => buffer(wout * (i + 1) - 1, wout * i) }
+  val last_piece = (piece_idx === UInt(n_pieces - 1))
+  val sending = Reg(init = Bool(false))
+  val in_last = Reg(Bool())
+
+  when (io.in.fire()) {
+    buffer := io.in.bits.data
+    in_last := io.in.bits.last
+    sending := Bool(true)
+  }
+  when (pkt_done) { sending := Bool(false) }
+
+  io.out.valid := sending
+  io.out.bits.data := pieces(piece_idx)
+  io.out.bits.last := in_last && last_piece
+  io.in.ready := !sending
+}
+
+class StreamExpander(win: Int, wout: Int) extends Module {
+  require(win < wout, "Stream expander input width must be smaller than input width")
+  require(wout % win == 0, "Stream narrower output width must be multiple of input width")
+
+  val io = new Bundle {
+    val in = Decoupled(new StreamChannel(win)).flip
+    val out = Decoupled(new StreamChannel(wout))
+  }
+
+  val n_pieces = wout / win
+  val buffer = Reg(Vec(n_pieces, UInt(width = win)))
+  val last = Reg(Bool())
+  val collecting = Reg(init = Bool(true))
+  val (piece_idx, pkt_done) = Counter(io.in.fire(), n_pieces)
+
+  when (io.in.fire()) { buffer(piece_idx) := io.in.bits.data }
+  when (pkt_done) { last := io.in.bits.last; collecting := Bool(false) }
+  when (io.out.fire()) { collecting := Bool(true) }
+
+  io.in.ready := collecting
+  io.out.valid := !collecting
+  io.out.bits.data := buffer.toBits
+  io.out.bits.last := last
+}
+
+object StreamUtils {
+  def connectStreams(a: StreamIO, b: StreamIO) {
+    a.in <> b.out
+    b.in <> a.out
+  }
+}
+
+trait Serializable {
+  def nbytes: Int
+}
+
+class Serializer[T <: Data with Serializable](typ: T) extends Module {
+  val io = new Bundle {
+    val in = Decoupled(typ).flip
+    val out = Decoupled(new StreamChannel(8))
+  }
+
+  val narrower = Module(new StreamNarrower(typ.nbytes * 8, 8))
+  narrower.io.in.bits.data := io.in.bits.toBits
+  narrower.io.in.bits.last := Bool(true)
+  narrower.io.in.valid := io.in.valid
+  io.in.ready := narrower.io.in.ready
+  io.out <> narrower.io.out
+}
+
+class Deserializer[T <: Data with Serializable](typ: T) extends Module {
+  val io = new Bundle {
+    val in = Decoupled(new StreamChannel(8)).flip
+    val out = Decoupled(typ)
+  }
+
+  val expander = Module(new StreamExpander(8, 8 * typ.nbytes))
+  expander.io.in <> io.in
+  io.out.valid := expander.io.out.valid
+  io.out.bits := typ.cloneType.fromBits(expander.io.out.bits.data)
+  expander.io.out.ready := io.out.ready
+}