diff --git a/core/build.sbt b/core/build.sbt
index eeeec35..7a45bf0 100644
--- a/core/build.sbt
+++ b/core/build.sbt
@@ -4,7 +4,7 @@ resolvers ++= Seq(
 
 libraryDependencies ++= {
   Seq(
-    "co.fs2"            %% "fs2-core" % "0.10.1",
-    "io.verizon.ermine" %% "parser"   % "0.5.8"
+    "co.fs2"            %% "fs2-core" % "1.0.0",
+    "io.verizon.ermine" %% "parser"   % "0.5.9"
   )
 }
diff --git a/core/src/main/scala/knobs/BaseConfig.scala b/core/src/main/scala/knobs/BaseConfig.scala
index 4f53366..616cc6c 100644
--- a/core/src/main/scala/knobs/BaseConfig.scala
+++ b/core/src/main/scala/knobs/BaseConfig.scala
@@ -17,9 +17,9 @@
 package knobs
 
 import cats._
-import cats.effect.Effect
+import cats.effect.ConcurrentEffect
 import cats.implicits._
-import fs2.async.Ref
+import cats.effect.concurrent.Ref
 
 /**
  * Global configuration data. This is the top-level config from which
@@ -41,12 +41,12 @@ case class BaseConfig[F[_]](paths: Ref[F, List[(Name, KnobsResource)]],
   def at(root: String)(implicit F: Functor[F]): F[Config] =
     cfgMap.get.map(Config(_).subconfig(root))
 
-  def reload(implicit F: Effect[F]): F[Unit] = for {
+  def reload(implicit F: ConcurrentEffect[F]): F[Unit] = for {
     ps <- paths.get
     mp <- loadFiles(ps.map(_._2)).flatMap(flatten(ps, _))
-    m  <- cfgMap.modify2(m => (mp, m))
+    m  <- cfgMap.modify(m => (mp, m))
     s  <- subs.get
-    _ <- notifySubscribers(m._2, mp, s)
+    _ <- notifySubscribers(m, mp, s)
   } yield ()
 }
 
diff --git a/core/src/main/scala/knobs/MutableConfig.scala b/core/src/main/scala/knobs/MutableConfig.scala
index 3a01be6..ff8165c 100644
--- a/core/src/main/scala/knobs/MutableConfig.scala
+++ b/core/src/main/scala/knobs/MutableConfig.scala
@@ -17,12 +17,11 @@
 package knobs
 
 import cats._
-import cats.effect.{Effect, Sync}
+import cats.effect.{Effect, Sync, Concurrent, ConcurrentEffect}
 import cats.implicits._
 import fs2.Stream
-import fs2.async.signalOf
+import fs2.concurrent.SignallingRef
 
-import scala.concurrent.ExecutionContext
 
 /** Mutable, reloadable, configuration data */
 case class MutableConfig[F[_]](root: String, base: BaseConfig[F]) {
@@ -41,23 +40,23 @@ case class MutableConfig[F[_]](root: String, base: BaseConfig[F]) {
    * just the local section. Any overridden properties set with `addProperties`
    * will disappear.
    */
-  def reload(implicit F: Effect[F]): F[Unit] = base.reload
+  def reload(implicit F: ConcurrentEffect[F]): F[Unit] = base.reload
 
   /**
    * Add additional files to this `MutableConfig`, causing it to be reloaded to
    * add their contents.
    */
-  def add(paths: List[KnobsResource])(implicit F: Effect[F]): F[Unit] =
+  def add(paths: List[KnobsResource])(implicit F: ConcurrentEffect[F]): F[Unit] =
     addGroups(paths.map(x => ("", x)))
 
   /**
    * Add additional files to named groups in this `MutableConfig`, causing it to be
    * reloaded to add their contents.
    */
-  def addGroups(paths: List[(Name, KnobsResource)])(implicit F: Effect[F]): F[Unit] = {
+  def addGroups(paths: List[(Name, KnobsResource)])(implicit F: ConcurrentEffect[F]): F[Unit] = {
     def fix[A](p: (String, A)) = (addDot(p._1), p._2)
     for {
-      _ <- base.paths.modify(prev => prev ++ paths.map(fix))
+      _ <- base.paths.update(prev => prev ++ paths.map(fix))
       _ <- base.reload
     } yield ()
   }
@@ -68,11 +67,11 @@ case class MutableConfig[F[_]](root: String, base: BaseConfig[F]) {
    * will be lost.
    */
   def addEnv(props: Env)(implicit F: Effect[F]): F[Unit] = for {
-    p <- base.cfgMap.modify2 { m =>
+    p <- base.cfgMap.modify { m =>
       val mp = m ++ props.map { case (k, v) => (root + k, v) }
       (mp, (m, mp))
     }
-    (_, (m, mp)) = p
+    (m, mp) = p
     subs <- base.subs.get
     _ <- notifySubscribers(m, mp, subs)
   } yield ()
@@ -156,20 +155,20 @@ case class MutableConfig[F[_]](root: String, base: BaseConfig[F]) {
    * Subscribe to notifications. The given handler will be invoked when any
    * change occurs to a configuration property that matches the pattern.
    */
-  def subscribe(p: Pattern, h: ChangeHandler[F])(implicit F: Apply[F]): F[Unit] =
-    base.subs.modify { map =>
+  def subscribe(p: Pattern, h: ChangeHandler[F]): F[Unit] =
+    base.subs.update { map =>
       map.get(p.local(root)) match {
         case None           => map + ((p.local(root), List(h)))
         case Some(existing) => map + ((p.local(root), existing ++ List(h)))
       }
-    }.void
+    }
 
   /**
    * A process that produces chages to the configuration properties that match
    * the given pattern
    */
-  def changes(p: Pattern)(implicit F: Effect[F], ec: ExecutionContext): Stream[F, (Name, Option[CfgValue])] = {
-    val signal = signalOf[F, (Name, Option[CfgValue])](("", None)) // TP: Not sure about the soundness of this default?
+  def changes(p: Pattern)(implicit F: Concurrent[F]): Stream[F, (Name, Option[CfgValue])] = {
+    val signal = SignallingRef[F, (Name, Option[CfgValue])](("", None)) // TP: Not sure about the soundness of this default?
 
     Stream.eval {
       for {
diff --git a/core/src/main/scala/knobs/Resource.scala b/core/src/main/scala/knobs/Resource.scala
index db0b856..8700ce3 100644
--- a/core/src/main/scala/knobs/Resource.scala
+++ b/core/src/main/scala/knobs/Resource.scala
@@ -25,7 +25,7 @@ import scala.collection.JavaConverters._
 
 import cats.Show
 import cats.data.NonEmptyVector
-import cats.effect.{Async, Effect, Sync}
+import cats.effect.{Async, Sync, Concurrent}
 import cats.implicits._
 import fs2.Stream
 
@@ -50,7 +50,7 @@ trait Resource[R] extends Show[R] {
 }
 
 trait Watchable[R] extends Resource[R] {
-  def watch[F[_]](path: Worth[R])(implicit F: Effect[F]): F[(List[Directive], Stream[F, Unit])]
+  def watch[F[_]](path: Worth[R])(implicit F: Concurrent[F]): F[(List[Directive], Stream[F, Unit])]
 }
 
 /** An existential resource. Equivalent to the (Haskell-style) type `exists r. Resource r ⇒ r` */
@@ -93,7 +93,7 @@ object FileResource {
    * Optionally creates a process to watch changes to the file and
    * reload any `MutableConfig` if it has changed.
    */
-  def apply(f: File, watched: Boolean = true)(implicit ec: ExecutionContext): ResourceBox = {
+  def apply(f: File, watched: Boolean = true): ResourceBox = {
     val _ = watched
     Watched(f.getCanonicalFile)
   }
@@ -102,7 +102,7 @@ object FileResource {
    * Creates a new resource that loads a configuration from a file.
    * Does not watch the file for changes or reload the config automatically.
    */
-  def unwatched(f: File)(implicit ec: ExecutionContext): ResourceBox = Resource.box(f.getCanonicalFile)
+  def unwatched(f: File): ResourceBox = Resource.box(f.getCanonicalFile)
 }
 
 object ClassPathResource {
@@ -152,7 +152,7 @@ object Resource {
 
   private val watchService: WatchService = FileSystems.getDefault.newWatchService
   private def watchStream[F[_]](implicit F: Async[F]): Stream[F, WatchEvent[_]] =
-    Stream.eval(F.shift(watchPool) *> F.delay(watchService.take)).flatMap(s =>
+    Stream.eval(Async.shift[F](watchPool) *> F.delay(watchService.take)).flatMap(s =>
       Stream.emits(s.pollEvents.asScala)).repeat
 
   /** Construct a new boxed resource from a valid `Resource` */
@@ -222,7 +222,7 @@ object Resource {
     } yield watchStream.filter(_.context == f)
   }
 
-  implicit def fileResource(implicit ec: ExecutionContext): Watchable[File] = new Watchable[File] {
+  implicit def fileResource: Watchable[File] = new Watchable[File] {
     def resolve(r: File, child: String): File =
       new File(resolveName(r.getPath, child))
 
@@ -231,11 +231,11 @@ object Resource {
 
     override def show(r: File) = r.toString
 
-    def watch[F[_]](path: Worth[File])(implicit F: Effect[F]) = for {
+    def watch[F[_]](path: Worth[File])(implicit F: Concurrent[F]) = for {
       ds <- load(path)
       rs <- recursiveImports(path.worth, ds)
       es <- (path.worth :: rs).traverse(f => watchEvent(f.toPath))
-    } yield (ds, Stream.emits(es.map(_.map(_ => ()))).joinUnbounded)
+    } yield (ds, Stream.emits(es.map(_.map(_ => ()))).parJoinUnbounded)
   }
 
   implicit def uriResource: Resource[URI] = new Resource[URI] {
diff --git a/core/src/main/scala/knobs/package.scala b/core/src/main/scala/knobs/package.scala
index e2c766e..7172cb5 100644
--- a/core/src/main/scala/knobs/package.scala
+++ b/core/src/main/scala/knobs/package.scala
@@ -17,8 +17,7 @@
 import cats.effect._
 import cats.implicits._
 import fs2.Stream
-import fs2.async.Ref
-import scala.concurrent.ExecutionContext
+import cats.effect.concurrent.Ref
 
 package object knobs {
   import Resource._
@@ -55,9 +54,8 @@ package object knobs {
    * first time they are opened, so you can specify a file name such as
    * `"$(HOME)/myapp.cfg"`.
    */
-  def load[F[_]: Effect](files: List[KnobsResource],
-           pool: ExecutionContext = Resource.notificationPool): F[MutableConfig[F]] =
-    loadp(files.map(f => ("", f)), pool).map(MutableConfig("", _))
+  def load[F[_]: ConcurrentEffect](files: List[KnobsResource]): F[MutableConfig[F]] =
+    loadp(files.map(f => ("", f))).map(MutableConfig("", _))
 
   /**
    * Create an immutable `Config` from the contents of the named files. Throws an
@@ -67,22 +65,20 @@ package object knobs {
    * first time they are opened, so you can specify a file name such as
    * `"$(HOME)/myapp.cfg"`.
    */
-  def loadImmutable[F[_]: Effect](files: List[KnobsResource],
-                    pool: ExecutionContext = Resource.notificationPool): F[Config] =
+  def loadImmutable[F[_]: ConcurrentEffect](files: List[KnobsResource]): F[Config] =
     load(files.map(_.map {
       case WatchBox(b, w) => ResourceBox(b)(w)
       case x => x
-    }), pool).flatMap(_.immutable)
+    })).flatMap(_.immutable)
 
   /**
    * Create a `MutableConfig` from the contents of the named files, placing them
    * into named prefixes.
    */
-  def loadGroups[F[_]: Effect](files: List[(Name, KnobsResource)],
-                 pool: ExecutionContext = Resource.notificationPool): F[MutableConfig[F]] =
-    loadp(files, pool).map(MutableConfig("", _))
+  def loadGroups[F[_]: ConcurrentEffect](files: List[(Name, KnobsResource)]): F[MutableConfig[F]] =
+    loadp(files).map(MutableConfig("", _))
 
-  private [knobs] def loadFiles[F[_]: Effect](paths: List[KnobsResource]): F[Loaded[F]] = {
+  private [knobs] def loadFiles[F[_]: ConcurrentEffect](paths: List[KnobsResource]): F[Loaded[F]] = {
     def go(seen: Loaded[F], path: KnobsResource): F[Loaded[F]] = {
       def notSeen(n: KnobsResource): Boolean = seen.get(n).isEmpty
       for {
@@ -98,16 +94,15 @@ package object knobs {
   }
 
   private [knobs] def loadp[F[_]](
-    paths: List[(Name, KnobsResource)],
-    pool: ExecutionContext = Resource.notificationPool)(implicit F: Effect[F]): F[BaseConfig[F]] = {
-      implicit val implicitPool = pool
+    paths: List[(Name, KnobsResource)]
+  )(implicit F: ConcurrentEffect[F]): F[BaseConfig[F]] = {
       for {
         loaded <- loadFiles(paths.map(_._2))
-        p <- Ref(paths)
-        m <- flatten(paths, loaded).flatMap(Ref(_))
-        s <- Ref(Map[Pattern, List[ChangeHandler[F]]]())
+        p <- Ref[F].of(paths)
+        m <- flatten(paths, loaded).flatMap(Ref[F].of(_))
+        s <- Ref[F].of(Map[Pattern, List[ChangeHandler[F]]]())
         bc = BaseConfig(paths = p, cfgMap = m, subs = s)
-        ticks = Stream.emits(loaded.values.map(_._2).toSeq).joinUnbounded
+        ticks = Stream.emits(loaded.values.map(_._2).toSeq).parJoinUnbounded
         _ <- F.delay(F.runAsync(ticks.evalMap(_ => bc.reload).compile.drain)(_ => IO.unit).unsafeRunSync)
       } yield bc
     }
@@ -222,7 +217,7 @@ package object knobs {
       implicitly[Resource[R]].load(Required(r)).flatMap(dds =>
         recursiveImports(r, dds))))
 
-  private [knobs] def loadOne[F[_]: Effect](path: KnobsResource): F[(List[Directive], Stream[F, Unit])] = {
+  private [knobs] def loadOne[F[_]: ConcurrentEffect](path: KnobsResource): F[(List[Directive], Stream[F, Unit])] = {
     val box = path.worth
     val r: box.R = box.resource
     box.watchable match {
diff --git a/core/src/test/scala/knobs/FileWatcherTest.scala b/core/src/test/scala/knobs/FileWatcherTest.scala
index 00800fb..415ac9c 100644
--- a/core/src/test/scala/knobs/FileWatcherTest.scala
+++ b/core/src/test/scala/knobs/FileWatcherTest.scala
@@ -16,28 +16,32 @@
 //: ----------------------------------------------------------------------------
 package knobs
 
-import fs2.async.Ref
-import java.nio.file.{ Files, Paths }
+
+import cats.effect.concurrent._
+import java.nio.file.{Files, Paths}
 import java.util.concurrent.CountDownLatch
+
 import org.scalacheck._
 import org.scalacheck.Prop._
-import scala.concurrent.ExecutionContext.Implicits.global
-
 import cats.effect.IO
 
+import scala.concurrent.ExecutionContext
+
 object FileWatcherTests extends Properties("FileWatch") {
 
+  implicit val cs = IO.contextShift(ExecutionContext.global)
+
   property("file watch") = {
     val mutantUri = Thread.currentThread.getContextClassLoader.getResource("mutant.cfg").toURI
     val mutantPath = Paths.get(mutantUri)
     val latch = new CountDownLatch(1)
     val prg = for {
-      ref <- Ref[IO, String]("")
+      ref <- Ref.of[IO, String]("")
       _   <- IO(Files.write(mutantPath, "foo = \"bletch\"\n".getBytes))
       cfg <- load[IO](List(Required(FileResource(mutantPath.toFile))))
       _ <- cfg.subscribe(Exact("foo"), {
         case ("foo", Some(t: CfgText)) =>
-          ref.setSync(t.pretty).flatMap(_ => IO(latch.countDown))
+          ref.set(t.pretty).flatMap(_ => IO(latch.countDown))
         case _ => {
           IO(latch.countDown)
         }
diff --git a/core/src/test/scala/knobs/Test.scala b/core/src/test/scala/knobs/Test.scala
index df57cef..5769461 100644
--- a/core/src/test/scala/knobs/Test.scala
+++ b/core/src/test/scala/knobs/Test.scala
@@ -18,11 +18,14 @@ package knobs
 
 import org.scalacheck._
 import Prop._
-import scala.concurrent.duration._
 
+import scala.concurrent.duration._
 import cats.effect.IO
 import cats.implicits._
 
+import scala.concurrent.ExecutionContext
+
+
 object Test extends Properties("Knobs") {
 
   // TODO remove when available in Scalacheck
@@ -30,6 +33,8 @@ object Test extends Properties("Knobs") {
   private implicit val arbFiniteDuration: Arbitrary[FiniteDuration] = Arbitrary(
     Gen.chooseNum(Long.MinValue + 1, Long.MaxValue).map(Duration.fromNanos))
 
+  implicit val cs = IO.contextShift(ExecutionContext.global)
+
   def withLoad[A](files: List[KnobsResource])(
     t: MutableConfig[IO] => IO[A]): IO[A] = for {
       mb <- load[IO](files)
diff --git a/typesafe/build.sbt b/typesafe/build.sbt
index e4ce45b..c1f3c5c 100644
--- a/typesafe/build.sbt
+++ b/typesafe/build.sbt
@@ -1,2 +1,2 @@
 // 1.3.0 is out but it depends on java 1.8.
-libraryDependencies += "com.typesafe" % "config" % "1.2.1"
+libraryDependencies += "com.typesafe" % "config" % "1.3.3"
diff --git a/version.sbt b/version.sbt
index c0c0702..b8b4128 100644
--- a/version.sbt
+++ b/version.sbt
@@ -1 +1 @@
-version in ThisBuild := "6.0.0-SNAPSHOT"
+version in ThisBuild := "7.0.0-SNAPSHOT"
diff --git a/zookeeper/build.sbt b/zookeeper/build.sbt
index 615f38f..1743371 100644
--- a/zookeeper/build.sbt
+++ b/zookeeper/build.sbt
@@ -1,4 +1,4 @@
 libraryDependencies ++= Seq(
-  "org.apache.curator" % "curator-framework" % "2.8.0",
-  "org.apache.curator" % "curator-test" % "2.8.0" % "test"
+  "org.apache.curator" % "curator-framework" % "4.0.1",
+  "org.apache.curator" % "curator-test" % "4.0.1" % "test"
 )
diff --git a/zookeeper/src/main/scala/knobs/Zookeeper.scala b/zookeeper/src/main/scala/knobs/Zookeeper.scala
index fa3464c..4c8bab9 100644
--- a/zookeeper/src/main/scala/knobs/Zookeeper.scala
+++ b/zookeeper/src/main/scala/knobs/Zookeeper.scala
@@ -22,12 +22,11 @@ import org.apache.curator.retry._
 import org.apache.zookeeper.WatchedEvent
 import org.apache.zookeeper.Watcher.Event.EventType._
 
-import scala.concurrent.ExecutionContext
-
-import cats.effect.{Async, Effect, Sync}
+import cats.effect.{Async, Sync, ConcurrentEffect, Concurrent}
 import cats.implicits._
 import fs2.Stream
 
+
 /**
  * A ZNode contains a `path` to a node in the ZooKeeper tree
  * provided by the given `client`. The `client` is assumed to be started.
@@ -56,7 +55,7 @@ object ZooKeeper {
       } catch { case e: Exception => k(Left(e)) }
     }).repeat
 
-  implicit def zkResource(implicit ec: ExecutionContext): Watchable[ZNode] = new Watchable[ZNode] {
+  implicit def zkResource: Watchable[ZNode] = new Watchable[ZNode] {
     def resolve(r: ZNode, child: Path): ZNode =
       r.copy(path = Resource.resolveName(r.path, child))
     def load[F[_]](node: Worth[ZNode])(implicit F: Sync[F]) = {
@@ -65,18 +64,18 @@ object ZooKeeper {
         new String(c.getData.forPath(path).map(_.toChar))
       })
     }
-    def watch[F[_]](node: Worth[ZNode])(implicit F: Effect[F]) = for {
+    def watch[F[_]](node: Worth[ZNode])(implicit F: Concurrent[F]) = for {
       ds <- load(node)
       rs <- recursiveImports(node.worth, ds)
       reloads <- F.delay { Stream.emits(node.worth +: rs).map {
         case ZNode(c, path) => watchEvent(c, path).map(_ => ())
       }}
-    } yield (ds, reloads.joinUnbounded)
+    } yield (ds, reloads.parJoinUnbounded)
 
     def show(t: ZNode): String = t.toString
   }
 
-  private def doZK[F[_]](config: List[KnobsResource])(implicit F: Effect[F], ec: ExecutionContext): F[(ResourceBox, CuratorFramework)] = {
+  private def doZK[F[_]](config: List[KnobsResource])(implicit F: ConcurrentEffect[F]): F[(ResourceBox, CuratorFramework)] = {
 
     val retryPolicy = new ExponentialBackoffRetry(1000, 3)
 
@@ -113,7 +112,7 @@ object ZooKeeper {
    * } yield () }.run
    * ```
    */
-  def withDefault[F[_]](k: ResourceBox => F[Unit])(implicit F: Effect[F], ec: ExecutionContext): F[Unit] = safe(k)
+  def withDefault[F[_]](k: ResourceBox => F[Unit])(implicit F: ConcurrentEffect[F]): F[Unit] = safe(k)
 
   /**
    * IO-based API. Works just like `withDefault` except it loads configuration from
@@ -130,9 +129,9 @@ object ZooKeeper {
    * } yield () }.run
    * ```
    */
-  def fromResource[F[_]](customConfig: List[KnobsResource])(k: ResourceBox => F[Unit])(implicit F: Effect[F], ec: ExecutionContext): F[Unit] = safe(k, customConfig)
+   def fromResource[F[_]](customConfig: List[KnobsResource])(k: ResourceBox => F[Unit])(implicit F: ConcurrentEffect[F]): F[Unit] = safe(k, customConfig)
 
-  protected def safe[F[_]](k: ResourceBox => F[Unit], config: List[KnobsResource] = null)(implicit F: Effect[F], ec: ExecutionContext): F[Unit] = for {
+  protected def safe[F[_]](k: ResourceBox => F[Unit], config: List[KnobsResource] = null)(implicit F: ConcurrentEffect[F]): F[Unit] = for {
     p <- doZK(config)
     (box, c) = p
     _ <- k(box)
diff --git a/zookeeper/src/test/scala/knobs/ZookeeperTest.scala b/zookeeper/src/test/scala/knobs/ZookeeperTest.scala
index 6654eb7..bbc319d 100644
--- a/zookeeper/src/test/scala/knobs/ZookeeperTest.scala
+++ b/zookeeper/src/test/scala/knobs/ZookeeperTest.scala
@@ -18,19 +18,23 @@ package knobs
 
 import Resource._
 import cats.effect.IO
-import fs2.async.Ref
+import cats.effect.concurrent.Ref
 import java.util.concurrent.CountDownLatch
+
 import org.apache.curator.framework._
 import org.apache.curator.retry._
 import org.apache.curator.test._
 import org.scalacheck.Prop._
 import org.scalacheck._
-import scala.concurrent.ExecutionContext.Implicits.global
+
+import scala.concurrent.ExecutionContext
 
 object ZooKeeperTests extends Properties("ZooKeeper") {
 
   val retryPolicy = new ExponentialBackoffRetry(1000, 3)
 
+  implicit val cs = IO.contextShift(ExecutionContext.global)
+
   import ZooKeeper._
 
   property("load config") = {
@@ -56,12 +60,12 @@ object ZooKeeperTests extends Properties("ZooKeeper") {
     c.create.forPath("/knobs.cfg", "foo = 10\n".toArray.map(_.toByte))
     val latch = new CountDownLatch(1)
     val prg = for {
-      ref <- Ref[IO, Int](0)
+      ref <- Ref.of[IO, Int](0)
       cfg <- load[IO](List(Required(Watched(ZNode(c, "/knobs.cfg")))))
       n1 <- cfg.require[Int]("foo")
       _ <- cfg.subscribe(Exact("foo"), {
         case ("foo", Some(CfgNumber(n))) =>
-          ref.setSync(n.toInt).flatMap(_ => IO(latch.countDown))
+          ref.set(n.toInt).flatMap(_ => IO(latch.countDown))
         case _ => IO(latch.countDown)
       })
       _ <- IO(Thread.sleep(1000))