diff --git a/packer_test/lib/plugin.go b/packer_test/lib/plugin.go
index c3a4b0fe7..28afb1adf 100644
--- a/packer_test/lib/plugin.go
+++ b/packer_test/lib/plugin.go
@@ -15,24 +15,29 @@ import (
 	"github.com/hashicorp/packer-plugin-sdk/plugin"
 )
 
-var compiledPlugins = struct {
+type compiledPlugins struct {
 	pluginVersions map[string]string
-	RWMutex        sync.RWMutex
-}{
-	pluginVersions: map[string]string{},
+	mutex          sync.Mutex
 }
 
-func StorePluginVersion(pluginVersion, path string) {
-	compiledPlugins.RWMutex.Lock()
-	defer compiledPlugins.RWMutex.Unlock()
-	compiledPlugins.pluginVersions[pluginVersion] = path
+func (ts *PackerTestSuite) StorePluginVersion(pluginVersion, path string) {
+	ts.compiledPlugins.mutex.Lock()
+	defer ts.compiledPlugins.mutex.Unlock()
+	if ts.compiledPlugins.pluginVersions == nil {
+		ts.compiledPlugins.pluginVersions = map[string]string{}
+	}
+
+	ts.compiledPlugins.pluginVersions[pluginVersion] = path
 }
 
-func LoadPluginVersion(pluginVersion string) (string, bool) {
-	compiledPlugins.RWMutex.RLock()
-	defer compiledPlugins.RWMutex.RUnlock()
+func (ts *PackerTestSuite) LoadPluginVersion(pluginVersion string) (string, bool) {
+	ts.compiledPlugins.mutex.Lock()
+	defer ts.compiledPlugins.mutex.Unlock()
+	if ts.compiledPlugins.pluginVersions == nil {
+		ts.compiledPlugins.pluginVersions = map[string]string{}
+	}
 
-	path, ok := compiledPlugins.pluginVersions[pluginVersion]
+	path, ok := ts.compiledPlugins.pluginVersions[pluginVersion]
 	return path, ok
 }
 
@@ -129,7 +134,7 @@ func (ts *PackerTestSuite) MakePluginDir(pluginVersions ...string) (pluginTempDi
 	}
 
 	for _, pluginVersion := range pluginVersions {
-		path, ok := LoadPluginVersion(pluginVersion)
+		path, ok := ts.LoadPluginVersion(pluginVersion)
 		if !ok {
 			err = fmt.Errorf("failed to get path to version %q, was it compiled?", pluginVersion)
 		}
diff --git a/packer_test/lib/suite.go b/packer_test/lib/suite.go
index f597c712c..2b8d10b7a 100644
--- a/packer_test/lib/suite.go
+++ b/packer_test/lib/suite.go
@@ -24,6 +24,13 @@ type PackerTestSuite struct {
 	// Since we don't necessarily want to manually compile Packer beforehand,
 	// we compile it on demand, and use this executable for the tests.
 	packerPath string
+	// compiledPlugins is the map of each compiled plugin to its path.
+	//
+	// This used to be global, but should be linked to the suite instead, as
+	// we may have multiple suites that exist, each with its own repo of
+	// plugins compiled for the purposes of the test, so as they all run
+	// within the same process space, they should be separate instances.
+	compiledPlugins compiledPlugins
 }
 
 func (ts *PackerTestSuite) buildPluginVersion(waitgroup *sync.WaitGroup, versionString string, t *testing.T) {
@@ -58,7 +65,7 @@ func (ts *PackerTestSuite) CompileTestPluginVersions(t *testing.T, versions ...s
 // though, deletion is the caller's responsibility.
 func (ts *PackerTestSuite) BuildSimplePlugin(versionString string, t *testing.T) string {
 	// Only build plugin binary if not already done beforehand
-	path, ok := LoadPluginVersion(versionString)
+	path, ok := ts.LoadPluginVersion(versionString)
 	if ok {
 		return path
 	}
@@ -81,7 +88,7 @@ func (ts *PackerTestSuite) BuildSimplePlugin(versionString string, t *testing.T)
 		t.Fatalf("failed to compile plugin binary: %s\ncompiler logs: %s", err, logs)
 	}
 
-	StorePluginVersion(v.String(), outBin)
+	ts.StorePluginVersion(v.String(), outBin)
 
 	return outBin
 }