diff --git a/boomer.go b/boomer.go
index eda4a4f2..29aa144c 100644
--- a/boomer.go
+++ b/boomer.go
@@ -9,27 +9,27 @@ import (
 	"github.com/httprunner/hrp/internal/ga"
 )
 
-func NewBoomer(spawnCount int, spawnRate float64) *hrpBoomer {
-	b := &hrpBoomer{
+func NewBoomer(spawnCount int, spawnRate float64) *HRPBoomer {
+	b := &HRPBoomer{
 		Boomer: boomer.NewStandaloneBoomer(spawnCount, spawnRate),
 		debug:  false,
 	}
 	return b
 }
 
-type hrpBoomer struct {
+type HRPBoomer struct {
 	*boomer.Boomer
 	debug bool
 }
 
 // SetDebug configures whether to log HTTP request and response content.
-func (b *hrpBoomer) SetDebug(debug bool) *hrpBoomer {
+func (b *HRPBoomer) SetDebug(debug bool) *HRPBoomer {
 	b.debug = debug
 	return b
 }
 
 // Run starts to run load test for one or multiple testcases.
-func (b *hrpBoomer) Run(testcases ...ITestCase) {
+func (b *HRPBoomer) Run(testcases ...ITestCase) {
 	event := ga.EventTracking{
 		Category: "RunLoadTests",
 		Action:   "hrp boom",
@@ -51,7 +51,7 @@ func (b *hrpBoomer) Run(testcases ...ITestCase) {
 	b.Boomer.Run(taskSlice...)
 }
 
-func (b *hrpBoomer) convertBoomerTask(testcase *TestCase) *boomer.Task {
+func (b *HRPBoomer) convertBoomerTask(testcase *TestCase) *boomer.Task {
 	hrpRunner := NewRunner(nil).SetDebug(b.debug)
 	config := testcase.Config.ToStruct()
 	return &boomer.Task{
diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index 4f2f8207..1f7d3a6f 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -2,7 +2,7 @@
 
 ## v0.3.1 (2021-12-30)
 
-- feat: set ulimit to 10240 before load testing
+- fix: set ulimit to 10240 before load testing
 - fix: concurrent map writes in load testing
 
 ## v0.3.0 (2021-12-24)
diff --git a/runner.go b/runner.go
index a1b9d108..260816a1 100644
--- a/runner.go
+++ b/runner.go
@@ -28,11 +28,11 @@ func Run(testcases ...ITestCase) error {
 }
 
 // NewRunner constructs a new runner instance.
-func NewRunner(t *testing.T) *hrpRunner {
+func NewRunner(t *testing.T) *HRPRunner {
 	if t == nil {
 		t = &testing.T{}
 	}
-	return &hrpRunner{
+	return &HRPRunner{
 		t:        t,
 		failfast: true,  // default to failfast
 		debug:    false, // default to turn off debug
@@ -45,7 +45,7 @@ func NewRunner(t *testing.T) *hrpRunner {
 	}
 }
 
-type hrpRunner struct {
+type HRPRunner struct {
 	t        *testing.T
 	failfast bool
 	debug    bool
@@ -53,21 +53,21 @@ type hrpRunner struct {
 }
 
 // SetFailfast configures whether to stop running when one step fails.
-func (r *hrpRunner) SetFailfast(failfast bool) *hrpRunner {
+func (r *HRPRunner) SetFailfast(failfast bool) *HRPRunner {
 	log.Info().Bool("failfast", failfast).Msg("[init] SetFailfast")
 	r.failfast = failfast
 	return r
 }
 
 // SetDebug configures whether to log HTTP request and response content.
-func (r *hrpRunner) SetDebug(debug bool) *hrpRunner {
+func (r *HRPRunner) SetDebug(debug bool) *HRPRunner {
 	log.Info().Bool("debug", debug).Msg("[init] SetDebug")
 	r.debug = debug
 	return r
 }
 
 // SetProxyUrl configures the proxy URL, which is usually used to capture HTTP packets for debugging.
-func (r *hrpRunner) SetProxyUrl(proxyUrl string) *hrpRunner {
+func (r *HRPRunner) SetProxyUrl(proxyUrl string) *HRPRunner {
 	log.Info().Str("proxyUrl", proxyUrl).Msg("[init] SetProxyUrl")
 	p, err := url.Parse(proxyUrl)
 	if err != nil {
@@ -82,7 +82,7 @@ func (r *hrpRunner) SetProxyUrl(proxyUrl string) *hrpRunner {
 }
 
 // Run starts to execute one or multiple testcases.
-func (r *hrpRunner) Run(testcases ...ITestCase) error {
+func (r *HRPRunner) Run(testcases ...ITestCase) error {
 	event := ga.EventTracking{
 		Category: "RunAPITests",
 		Action:   "hrp run",
@@ -106,7 +106,7 @@ func (r *hrpRunner) Run(testcases ...ITestCase) error {
 	return nil
 }
 
-func (r *hrpRunner) newCaseRunner(testcase *TestCase) *caseRunner {
+func (r *HRPRunner) newCaseRunner(testcase *TestCase) *caseRunner {
 	caseRunner := &caseRunner{
 		TestCase:  testcase,
 		hrpRunner: r,
@@ -119,7 +119,7 @@ func (r *hrpRunner) newCaseRunner(testcase *TestCase) *caseRunner {
 // each testcase has its own caseRunner instance and share session variables.
 type caseRunner struct {
 	*TestCase
-	hrpRunner        *hrpRunner
+	hrpRunner        *HRPRunner
 	sessionVariables map[string]interface{}
 	// transactions stores transaction timing info.
 	// key is transaction name, value is map of transaction type and time, e.g. start time and end time.