diff --git a/cmd/seb/main.go b/cmd/seb/main.go
index c7fb584..fa24f72 100644
--- a/cmd/seb/main.go
+++ b/cmd/seb/main.go
@@ -55,8 +55,7 @@ var (
 
 func main() {
 	ops := buildbuild.NewGlobalOps()
-	// Disable BuildPlugin for now, it's too buggy on 1.8beta1
-	//ops.BuildPlugin = BuildPlugin
+	ops.BuildPlugin = BuildPlugin
 	flag.Usage = func() {
 		fmt.Fprintf(os.Stderr, "Usage: %s [options] [--] [<ninja-args>]\n", os.Args[0])
 		flag.PrintDefaults()
diff --git a/cmd/seb/plugin_dso.go b/cmd/seb/plugin_dso.go
index 4a70f77..4c6d268 100644
--- a/cmd/seb/plugin_dso.go
+++ b/cmd/seb/plugin_dso.go
@@ -1,6 +1,4 @@
-// Copyright 2018 Schibsted
-
-//+build go1.8
+// Copyright 2019 Schibsted
 
 package main
 
@@ -10,10 +8,14 @@ import (
 	"path"
 	"path/filepath"
 	"plugin"
+	"strings"
 
 	"github.com/schibsted/sebuild/pkg/buildbuild"
 )
 
+// BuildPlugin compiles a sebuild plugin in the given directory.
+// This function is in the main package primarily because early in the
+// plugin support it didn't work to load plugins from non-main packages.
 func BuildPlugin(ops *buildbuild.GlobalOps, ppath string) error {
 	binpath := path.Join(ops.Config.Buildpath, "obj/_plugins", ppath+".so")
 
@@ -26,12 +28,29 @@ func BuildPlugin(ops *buildbuild.GlobalOps, ppath string) error {
 	if err != nil {
 		return err
 	}
-	tmpdir := ops.TempDirWithPlugins([]string{ppath})
-	defer os.RemoveAll(tmpdir)
+
 	cmd := exec.Command("go", "build", "-buildmode=plugin", "-o", binabs)
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
-	cmd.Dir = tmpdir
+	cmd.Dir = ppath
+
+	cmd.Env = os.Environ()
+	for idx, str := range cmd.Env {
+		// Workaround weird go invocation of CC, it just picks the first word, ignoring others.
+		// Assume the last word not starting with - is the one we want
+		if strings.HasPrefix(str, "CC=") {
+			args := strings.Split(str[3:], " ")
+			var i int
+			for i = len(args) - 1; i > 0; i-- {
+				if len(args[i]) > 0 && args[i][0] != '-' {
+					break
+				}
+			}
+			cmd.Env[idx] = "CC=" + strings.Join(args[i:], " ")
+			break
+		}
+	}
+
 	err = cmd.Run()
 	if err != nil {
 		return err
diff --git a/cmd/seb/plugin_nodso.go b/cmd/seb/plugin_nodso.go
deleted file mode 100644
index 7119eb2..0000000
--- a/cmd/seb/plugin_nodso.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2018 Schibsted
-
-//+build !go1.8
-
-package main
-
-import "github.com/schibsted/sebuild/pkg/buildbuild"
-
-func BuildPlugin(ops *buildbuild.GlobalOps, ppath string) error {
-	// Return nil is ok since the plugin still won't be found in the parent code.
-	return nil
-}
diff --git a/internal/tools/gobuild.sh b/internal/tools/gobuild.sh
index 82e209a..05412d8 100755
--- a/internal/tools/gobuild.sh
+++ b/internal/tools/gobuild.sh
@@ -69,6 +69,13 @@ IFS="$orig_IFS"
 # Strip initial :
 GOPATH="${gopath:1}"
 
+# If we have an explicit GOPATH then disable go modules.
+# Probably will want to drop support for GOPATH quite soon, but that should be
+# a major release so it will have to wait for that.
+if [ -n "$GOPATH" ]; then
+	export GO111MODULE=off
+fi
+
 if [ -z "$mode" ]; then
 	mode="prog"
 fi
@@ -82,9 +89,6 @@ if [ "$mode" = "bench" ]; then
 	exec go test $GOBUILD_FLAGS $GOBUILD_TEST_FLAGS $PKG -bench $4
 fi
 if [ "$mode" = "cover_html" ]; then
-	# If we have a GOPATH then disable go modules or go 1.11 might fail
-	# to find the package due to assuming it to on based on $PWD.
-	[ -n "$GOPATH" ] && export GO111MODULE=off
 	exec go tool cover -html=$IN -o "$OUT"
 fi
 
diff --git a/pkg/buildbuild/config.go b/pkg/buildbuild/config.go
index e2bb38d..5bfd884 100644
--- a/pkg/buildbuild/config.go
+++ b/pkg/buildbuild/config.go
@@ -308,12 +308,7 @@ func (ops *GlobalOps) StartupPlugins(srcdir string, s *Scanner, flavors []string
 		}
 	}
 	if len(missingPlugins) > 0 {
-		ops.MaybeReExec()
-		if !ops.Options.Quiet {
-			fmt.Fprintf(os.Stderr, "Plugins not compiled: %s\n", strings.Join(missingPlugins, " "))
-		}
-		ops.RecompileWithPlugins()
-		ops.ReExec()
+		panic("Failed to load plugins: " + strings.Join(missingPlugins, ", "))
 	}
 
 	return ops.ParseDescriptorEnd
diff --git a/pkg/buildbuild/globalops.go b/pkg/buildbuild/globalops.go
index b864dab..d671934 100644
--- a/pkg/buildbuild/globalops.go
+++ b/pkg/buildbuild/globalops.go
@@ -8,10 +8,8 @@ package buildbuild
 import (
 	"log"
 	"os"
-	"os/exec"
 	"path/filepath"
 	"strings"
-	"syscall"
 )
 
 // Global build configuration.
@@ -164,17 +162,6 @@ func (ops *GlobalOps) RegisterGlob(srcdir, src string) {
 	}
 }
 
-func (ops *GlobalOps) ReExec() {
-	if _, ok := os.LookupEnv("BUILDTOOLDIR"); !ok {
-		btp := BuildtoolDir()
-		os.Setenv("BUILDTOOLDIR", btp)
-	}
-	binpath := filepath.Join(ops.Config.Buildpath, "obj", "_build_build")
-	if err := syscall.Exec(binpath, os.Args, syscall.Environ()); err != nil {
-		panic(err)
-	}
-}
-
 type PluginDep struct {
 	ppath string
 	os.FileInfo
@@ -217,46 +204,6 @@ func (ops *GlobalOps) PluginDeps() (deps []PluginDep) {
 	return
 }
 
-func (ops *GlobalOps) MaybeReExec() {
-	binpath := filepath.Join(ops.Config.Buildpath, "obj", "_build_build")
-	if binpath == os.Args[0] {
-		return
-	}
-	theirinfo, err := os.Stat(binpath)
-	if err != nil {
-		// If they don't exist then we proceed ourselves.
-		return
-	}
-	me, err := exec.LookPath(os.Args[0])
-	if err != nil {
-		var tmp error
-		me, tmp = filepath.EvalSymlinks("/proc/self/exe")
-		if tmp != nil {
-			// Return the original error, /proc/self is just a fallback.
-			panic(err)
-		}
-	}
-	if me == binpath {
-		return
-	}
-	myinfo, err := os.Stat(me)
-	if err != nil {
-		panic(err)
-	}
-	if !theirinfo.ModTime().After(myinfo.ModTime()) {
-		// If we're newer than them, then we can't trust them to be up to date.
-		return
-	}
-	// Check plugins as well.
-	deps := ops.PluginDeps()
-	for _, pi := range deps {
-		if !theirinfo.ModTime().After(pi.ModTime()) {
-			return
-		}
-	}
-	ops.ReExec()
-}
-
 func NormalizePath(basedir, p string) string {
 	if !strings.HasPrefix(p, ".") {
 		return p
diff --git a/test/exts/ext.go b/test/exts/ext.go
index 8b22c97..d7d34a6 100644
--- a/test/exts/ext.go
+++ b/test/exts/ext.go
@@ -1,6 +1,6 @@
 // Copyright 2018 Schibsted
 
-package exts
+package main
 
 import (
 	"strings"