diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b9a83196af..2031cb473d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -84,11 +84,9 @@ jobs:
         with:
           jvm: "zulu:17"
       - run: |
-          ./mill -i __.publishLocal &&\
           ./mill -i integration.test.jvm
         if: runner.os != 'Windows'
       - run: |
-          @call ./mill.bat -i __.publishLocal
           @call ./mill.bat -i integration.test.jvm
         shell: cmd
         if: runner.os == 'Windows'
@@ -127,11 +125,9 @@ jobs:
           if-no-files-found: error
           retention-days: 1
       - run: |
-          ./mill -i __.publishLocal &&\
           ./mill -i "integration.test.native"
         if: github.event_name == 'push' && runner.os != 'Windows'
       - run: |
-          ./mill.bat -i __.publishLocal
           ./mill.bat -i integration.test.native
         if: github.event_name == 'push' && runner.os == 'Windows'
         shell: bash
diff --git a/build.sc b/build.sc
index 21b745e904..10c67ea979 100644
--- a/build.sc
+++ b/build.sc
@@ -19,6 +19,8 @@ object Dependencies {
 
   def scalaVersions = Seq(scala212, scala213)
 
+  def serverScalaVersion = scala212
+
   def asmVersion         = "9.6"
   def coursierVersion    = "2.1.0-M6-53-gb4f448130"
   def graalvmVersion     = "22.2.0"
@@ -46,6 +48,7 @@ object Dependencies {
     ivy"com.github.plokhotnyuk.jsoniter-scala::jsoniter-scala-core:$jsoniterVersion"
   def jsoniterMacros =
     ivy"com.github.plokhotnyuk.jsoniter-scala::jsoniter-scala-macros:$jsoniterVersion"
+  def jsonrpc4s              = ivy"io.github.alexarchambault.bleep::jsonrpc4s:0.1.1"
   def junit                  = ivy"com.github.sbt:junit-interface:0.13.3"
   def libdaemonjvm           = ivy"io.github.alexarchambault.libdaemon::libdaemon:0.0.11"
   def libraryManagement      = ivy"org.scala-sbt::librarymanagement-ivy:1.9.3"
@@ -156,7 +159,11 @@ class Shared(val crossScalaVersion: String) extends BloopCrossSbtModule with Pub
     emptyZip()
   }
   def ivyDeps = super.ivyDeps() ++ Agg(
-    Dependencies.bsp4s.exclude(("com.github.plokhotnyuk.jsoniter-scala", "*")),
+    Dependencies.bsp4s
+      .exclude(("com.github.plokhotnyuk.jsoniter-scala", "*"))
+      .exclude(("me.vican.jorge", "jsonrpc4s_2.12"))
+      .exclude(("me.vican.jorge", "jsonrpc4s_2.13")),
+    Dependencies.jsonrpc4s,
     Dependencies.coursierInterface,
     Dependencies.jsoniterCore,
     Dependencies.log4j,
@@ -532,8 +539,8 @@ object `bloop-rifle` extends BloopCliModule {
          |
          |/** Build-time constants. Generated by mill. */
          |object Constants {
-         |  def bloopVersion = "${frontend(Dependencies.scala212).publishVersion()}"
-         |  def bloopScalaVersion = "${Dependencies.scala212}"
+         |  def bloopVersion = "${frontend(Dependencies.serverScalaVersion).publishVersion()}"
+         |  def bloopScalaVersion = "${Dependencies.serverScalaVersion}"
          |  def bspVersion = "${Dependencies.bsp4j.dep.version}"
          |}
          |""".stripMargin
@@ -607,6 +614,19 @@ object integration extends BloopCliModule {
       Dependencies.pprint
     )
 
+    private def repoRoot = os.pwd / "out" / "repo"
+    def localRepo = T {
+      val modules = Seq(
+        frontend(Dependencies.serverScalaVersion),
+        backend(Dependencies.serverScalaVersion),
+        shared(Dependencies.serverScalaVersion)
+      )
+      os.remove.all(repoRoot)
+      os.makeDir.all(repoRoot)
+      val tasks = modules.map(_.publishLocalNoFluff(repoRoot.toString))
+      define.Target.sequence(tasks)
+    }
+
     def forkEnv = super.forkEnv() ++ Seq(
       "BLOOP_CLI_TESTS_TMP_DIR" -> tmpDir()
     )
@@ -615,8 +635,10 @@ object integration extends BloopCliModule {
       def test(args: String*) = {
         val argsTask = T.task {
           val launcher = launcherTask().path
+          localRepo()
           val extraArgs = Seq(
-            s"-Dtest.bloop-cli.path=$launcher"
+            s"-Dtest.bloop-cli.path=$launcher",
+            s"-Dtest.bloop-cli.repo=$repoRoot"
           )
           args ++ extraArgs
         }
diff --git a/frontend/src/main/scala/bloop/bsp/BspServer.scala b/frontend/src/main/scala/bloop/bsp/BspServer.scala
index 23fc09e29e..23bc6682c1 100644
--- a/frontend/src/main/scala/bloop/bsp/BspServer.scala
+++ b/frontend/src/main/scala/bloop/bsp/BspServer.scala
@@ -163,6 +163,8 @@ object BspServer {
       case scala.util.Success(socket: ServerSocket) =>
         listenToConnection(handle, socket).onErrorRecover {
           case t =>
+            System.err.println("Exiting BSP server with:")
+            t.printStackTrace(System.err)
             state.withError(s"Exiting BSP server with ${t.getMessage}", t)
         }
       case scala.util.Failure(t: Throwable) =>
diff --git a/integration/test/src/bloop/cli/integration/BloopCliTests.scala b/integration/test/src/bloop/cli/integration/BloopCliTests.scala
index ef599a0bf5..8c3f8f08af 100644
--- a/integration/test/src/bloop/cli/integration/BloopCliTests.scala
+++ b/integration/test/src/bloop/cli/integration/BloopCliTests.scala
@@ -9,22 +9,21 @@ class BloopCliTests extends munit.FunSuite {
       val dirArgs = Seq[os.Shellable]("--daemon-dir", root / "daemon")
 
       os.proc(Launcher.launcher, "exit", dirArgs)
-        .call(cwd = root)
+        .call(cwd = root, stdin = os.Inherit, stdout = os.Inherit)
       val statusCheck0 = os.proc(Launcher.launcher, "status", dirArgs)
         .call(cwd = root)
         .out.trim()
       expect(statusCheck0 == "stopped")
 
-      val res = os.proc(Launcher.launcher, dirArgs, "about")
-        .call(cwd = root)
-      expect(res.out.text().startsWith("bloop v"))
+      os.proc(Launcher.launcher, dirArgs, "about")
+        .call(cwd = root, stdin = os.Inherit, stdout = os.Inherit, env = Launcher.extraEnv)
       val statusCheck1 = os.proc(Launcher.launcher, "status", dirArgs)
         .call(cwd = root)
         .out.trim()
       expect(statusCheck1 == "running")
 
       os.proc(Launcher.launcher, "exit", dirArgs)
-        .call(cwd = root)
+        .call(cwd = root, stdin = os.Inherit, stdout = os.Inherit)
       val statusCheck2 = os.proc(Launcher.launcher, "status", dirArgs)
         .call(cwd = root)
         .out.trim()
diff --git a/integration/test/src/bloop/cli/integration/BspTests.scala b/integration/test/src/bloop/cli/integration/BspTests.scala
new file mode 100644
index 0000000000..5f75c70a5c
--- /dev/null
+++ b/integration/test/src/bloop/cli/integration/BspTests.scala
@@ -0,0 +1,134 @@
+package bloop.cli.integration
+
+import java.net.{StandardProtocolFamily, UnixDomainSocketAddress}
+import java.nio.channels.SocketChannel
+import java.nio.charset.StandardCharsets
+import java.nio.ByteBuffer
+
+class BspTests extends munit.FunSuite {
+
+  test("no JSON junk in errors") {
+    TmpDir.fromTmpDir { root =>
+      val dirArgs = Seq[os.Shellable]("--daemon-dir", root / "daemon")
+      val bspFile = root / "bsp-socket"
+
+      val dummyMsg =
+        """{
+          |  "jsonrpc": "2.0",
+          |  "method": "workspace/buildTargetz",
+          |  "params": null,
+          |  "id": 2
+          |}""".stripMargin
+
+      var bspProc: os.SubProcess = null
+      var socket: SocketChannel  = null
+
+      try {
+        os.proc(Launcher.launcher, dirArgs, "about")
+          .call(cwd = root, stdin = os.Inherit, stdout = os.Inherit, env = Launcher.extraEnv)
+
+        bspProc =
+          os.proc(Launcher.launcher, dirArgs, "bsp", "--protocol", "local", "--socket", bspFile)
+            .spawn(cwd = root, stdin = os.Inherit, stdout = os.Inherit)
+
+        val addr         = UnixDomainSocketAddress.of(bspFile.toNIO)
+        var connected    = false
+        var attemptCount = 0
+
+        while (!connected && bspProc.isAlive() && attemptCount < 10) {
+          if (attemptCount > 0)
+            Thread.sleep(1000L)
+          attemptCount += 1
+
+          if (os.exists(bspFile)) {
+            socket = SocketChannel.open(StandardProtocolFamily.UNIX)
+            socket.connect(addr)
+            socket.finishConnect()
+            connected = true
+          }
+        }
+
+        if (!connected)
+          sys.error("Not connected to Bloop server via BSP :|")
+
+        def sendMsg(msg: String): Unit = {
+          val bytes = msg.getBytes(StandardCharsets.UTF_8)
+
+          def doWrite(buf: ByteBuffer): Unit =
+            if (buf.position() < buf.limit()) {
+              val written = socket.write(buf)
+              if (written == 0)
+                Thread.sleep(100L)
+              doWrite(buf)
+            }
+
+          doWrite(ByteBuffer.wrap(
+            (s"Content-Length: ${bytes.length}" + "\r\n\r\n").getBytes(StandardCharsets.UTF_8)
+          ))
+          doWrite(ByteBuffer.wrap(bytes))
+        }
+
+        sendMsg(dummyMsg)
+
+        val arr = Array.ofDim[Byte](10 * 1024)
+        val buf = ByteBuffer.wrap(arr)
+
+        // seems to do the job…
+        def doRead(buf: ByteBuffer, count: Int): Int = {
+          val read = socket.read(buf)
+          if (read <= 0 && count < 100) {
+            Thread.sleep(100L)
+            doRead(buf, count + 1)
+          }
+          else
+            read
+        }
+
+        val read = doRead(buf, 0)
+        assert(read > 0)
+
+        val resp = new String(arr, 0, read, StandardCharsets.UTF_8)
+
+        def validateJson(content: String): Boolean = {
+          assert(content.startsWith("{"))
+          assert(content.endsWith("}"))
+          val chars    = content.toCharArray
+          val objCount = Array.ofDim[Int](chars.length)
+          for (i <- 0 until chars.length) {
+            val previous = if (i == 0) 0 else objCount(i - 1)
+            val count    = previous + (if (chars(i) == '{') 1 else if (chars(i) == '}') -1 else 0)
+            objCount(i) = count
+          }
+          objCount.dropRight(1).forall(_ > 0)
+        }
+
+        resp.linesWithSeparators.toVector match {
+          case Seq(cl, empty, other @ _*)
+              if cl.startsWith("Content-Length:") && empty.trim.isEmpty =>
+            val json      = other.mkString
+            val validated = validateJson(json)
+            if (!validated)
+              pprint.err.log(json)
+            assert(validated, "Unexpected JSON response shape")
+          case _ =>
+            pprint.err.log(resp)
+            sys.error("Unexpected response shape")
+        }
+      }
+      finally {
+        if (socket != null)
+          socket.close()
+
+        if (bspProc != null) {
+          bspProc.waitFor(1000L)
+          if (bspProc.isAlive())
+            bspProc.close()
+
+          os.proc(Launcher.launcher, dirArgs, "exit")
+            .call(cwd = root, stdin = os.Inherit, stdout = os.Inherit, check = false)
+        }
+      }
+    }
+  }
+
+}
diff --git a/integration/test/src/bloop/cli/integration/Launcher.scala b/integration/test/src/bloop/cli/integration/Launcher.scala
index c2b824c4bd..436c15dd41 100644
--- a/integration/test/src/bloop/cli/integration/Launcher.scala
+++ b/integration/test/src/bloop/cli/integration/Launcher.scala
@@ -7,4 +7,14 @@ object Launcher {
     sys.error("test.bloop-cli.path not set")
   )
 
+  lazy val repoRoot = os.Path(sys.props.getOrElse(
+    "test.bloop-cli.repo",
+    sys.error("test.bloop-cli.repo not set")
+  ))
+
+  lazy val extraEnv =
+    Map(
+      "COURSIER_REPOSITORIES" -> s"ivy:${repoRoot.toNIO.toUri.toASCIIString}/[defaultPattern]|ivy2Local|central"
+    )
+
 }