diff --git a/blob.go b/blob.go
index b638c4f..c182e54 100644
--- a/blob.go
+++ b/blob.go
@@ -22,4 +22,3 @@ func (v Blob) Contents() []byte {
 	buffer := unsafe.Pointer(C.git_blob_rawcontent(v.ptr))
 	return C.GoBytes(buffer, size)
 }
-
diff --git a/checkout.go b/checkout.go
index 63637e2..e3471a0 100644
--- a/checkout.go
+++ b/checkout.go
@@ -10,6 +10,7 @@ git_checkout_opts git_checkout_opts_init() {
 import "C"
 import (
 	"os"
+	"runtime"
 )
 
 type CheckoutStrategy uint
@@ -35,10 +36,10 @@ const (
 
 type CheckoutOpts struct {
 	Strategy       CheckoutStrategy // Default will be a dry run
-	DisableFilters bool				// Don't apply filters like CRLF conversion
-	DirMode        os.FileMode		// Default is 0755
-	FileMode       os.FileMode		// Default is 0644 or 0755 as dictated by blob
-	FileOpenFlags  int				// Default is O_CREAT | O_TRUNC | O_WRONLY
+	DisableFilters bool             // Don't apply filters like CRLF conversion
+	DirMode        os.FileMode      // Default is 0755
+	FileMode       os.FileMode      // Default is 0644 or 0755 as dictated by blob
+	FileOpenFlags  int              // Default is O_CREAT | O_TRUNC | O_WRONLY
 }
 
 // Convert the CheckoutOpts struct to the corresponding C-struct
@@ -59,6 +60,9 @@ func (v *Repository) Checkout(opts *CheckoutOpts) error {
 	var copts C.git_checkout_opts
 	populateCheckoutOpts(&copts, opts)
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_checkout_head(v.ptr, &copts)
 	if ret < 0 {
 		return LastError()
@@ -72,6 +76,9 @@ func (v *Repository) CheckoutIndex(index *Index, opts *CheckoutOpts) error {
 	var copts C.git_checkout_opts
 	populateCheckoutOpts(&copts, opts)
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_checkout_index(v.ptr, index.ptr, &copts)
 	if ret < 0 {
 		return LastError()
diff --git a/commit.go b/commit.go
index cacaa33..498669e 100644
--- a/commit.go
+++ b/commit.go
@@ -9,8 +9,9 @@ extern int _go_git_treewalk(git_tree *tree, git_treewalk_mode mode, void *ptr);
 import "C"
 
 import (
-	"unsafe"
+	"runtime"
 	"time"
+	"unsafe"
 )
 
 // Commit
@@ -25,6 +26,9 @@ func (c Commit) Message() string {
 func (c Commit) Tree() (*Tree, error) {
 	var ptr *C.git_object
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	err := C.git_commit_tree(&ptr, c.ptr)
 	if err < 0 {
 		return nil, LastError()
@@ -48,12 +52,13 @@ func (c Commit) Committer() *Signature {
 }
 
 func (c *Commit) Parent(n uint) *Commit {
-	par := &Commit{}
-	ret := C.git_commit_parent(&par.ptr, c.ptr, C.uint(n))
+	var cobj *C.git_object
+	ret := C.git_commit_parent(&cobj, c.ptr, C.uint(n))
 	if ret != 0 {
 		return nil
 	}
-	return par
+
+	return allocObject(cobj).(*Commit)
 }
 
 func (c *Commit) ParentId(n uint) *Oid {
@@ -85,10 +90,10 @@ func newSignatureFromC(sig *C.git_signature) *Signature {
 // the offset in mintes, which is what git wants
 func (v *Signature) Offset() int {
 	_, offset := v.When.Zone()
-	return offset/60
+	return offset / 60
 }
 
-func (sig *Signature) toC() (*C.git_signature) {
+func (sig *Signature) toC() *C.git_signature {
 	var out *C.git_signature
 
 	name := C.CString(sig.Name)
diff --git a/config.go b/config.go
index dcad2a7..2aa073a 100644
--- a/config.go
+++ b/config.go
@@ -6,6 +6,7 @@ package git
 */
 import "C"
 import (
+	"runtime"
 	"unsafe"
 )
 
@@ -18,6 +19,9 @@ func (c *Config) LookupInt32(name string) (v int32, err error) {
 	cname := C.CString(name)
 	defer C.free(unsafe.Pointer(cname))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_config_get_int32(&out, c.ptr, cname)
 	if ret < 0 {
 		return 0, LastError()
@@ -31,6 +35,9 @@ func (c *Config) LookupInt64(name string) (v int64, err error) {
 	cname := C.CString(name)
 	defer C.free(unsafe.Pointer(cname))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_config_get_int64(&out, c.ptr, cname)
 	if ret < 0 {
 		return 0, LastError()
@@ -44,6 +51,9 @@ func (c *Config) LookupString(name string) (v string, err error) {
 	cname := C.CString(name)
 	defer C.free(unsafe.Pointer(cname))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_config_get_string(&ptr, c.ptr, cname)
 	if ret < 0 {
 		return "", LastError()
@@ -59,6 +69,9 @@ func (c *Config) Set(name, value string) (err error) {
 	cvalue := C.CString(value)
 	defer C.free(unsafe.Pointer(cvalue))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_config_set_string(c.ptr, cname, cvalue)
 	if ret < 0 {
 		return LastError()
@@ -66,3 +79,8 @@ func (c *Config) Set(name, value string) (err error) {
 
 	return nil
 }
+
+func (c *Config) Free() {
+	runtime.SetFinalizer(c, nil)
+	C.git_config_free(c.ptr)
+}
diff --git a/git.go b/git.go
index c663d2e..406ecb7 100644
--- a/git.go
+++ b/git.go
@@ -9,6 +9,7 @@ import "C"
 import (
 	"bytes"
 	"errors"
+	"runtime"
 	"strings"
 	"unsafe"
 )
@@ -57,6 +58,9 @@ func NewOidFromString(s string) (*Oid, error) {
 	cs := C.CString(s)
 	defer C.free(unsafe.Pointer(cs))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	if C.git_oid_fromstr(o.toC(), cs) < 0 {
 		return nil, LastError()
 	}
@@ -109,6 +113,10 @@ func ShortenOids(ids []*Oid, minlen int) (int, error) {
 	defer C.git_oid_shorten_free(shorten)
 
 	var ret C.int
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	for _, id := range ids {
 		buf := make([]byte, 41)
 		C.git_oid_fmt((*C.char)(unsafe.Pointer(&buf[0])), id.toC())
@@ -162,6 +170,9 @@ func Discover(start string, across_fs bool, ceiling_dirs []string) (string, erro
 	retpath := (*C.git_buf)(C.malloc(C.GIT_PATH_MAX))
 	defer C.git_buf_free(retpath)
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	r := C.git_repository_discover(retpath, cstart, cbool(across_fs), ceildirs)
 
 	if r == 0 {
diff --git a/git_test.go b/git_test.go
index 52aea1d..5534240 100644
--- a/git_test.go
+++ b/git_test.go
@@ -1,8 +1,8 @@
 package git
 
 import (
-	"testing"
 	"io/ioutil"
+	"testing"
 	"time"
 )
 
@@ -14,7 +14,7 @@ func createTestRepo(t *testing.T) *Repository {
 	checkFatal(t, err)
 
 	tmpfile := "README"
-	err = ioutil.WriteFile(path + "/" + tmpfile, []byte("foo\n"), 0644)
+	err = ioutil.WriteFile(path+"/"+tmpfile, []byte("foo\n"), 0644)
 	checkFatal(t, err)
 
 	return repo
@@ -44,4 +44,3 @@ func seedTestRepo(t *testing.T, repo *Repository) (*Oid, *Oid) {
 
 	return commitId, treeId
 }
-
diff --git a/index.go b/index.go
index 4a69c1e..ac5148c 100644
--- a/index.go
+++ b/index.go
@@ -24,6 +24,9 @@ func (v *Index) AddByPath(path string) error {
 	cstr := C.CString(path)
 	defer C.free(unsafe.Pointer(cstr))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_index_add_bypath(v.ptr, cstr)
 	if ret < 0 {
 		return LastError()
@@ -34,6 +37,10 @@ func (v *Index) AddByPath(path string) error {
 
 func (v *Index) WriteTree() (*Oid, error) {
 	oid := new(Oid)
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_index_write_tree(oid.toC(), v.ptr)
 	if ret < 0 {
 		return nil, LastError()
diff --git a/object.go b/object.go
index 090be1f..7834a1a 100644
--- a/object.go
+++ b/object.go
@@ -10,12 +10,12 @@ import "runtime"
 type ObjectType int
 
 const (
-	ObjectAny ObjectType = C.GIT_OBJ_ANY
-	ObjectBad            = C.GIT_OBJ_BAD
-	ObjectCommit         = C.GIT_OBJ_COMMIT
-	ObjectTree           = C.GIT_OBJ_TREE
-	ObjectBlob           = C.GIT_OBJ_BLOB
-	ObjectTag            = C.GIT_OBJ_TAG
+	ObjectAny    ObjectType = C.GIT_OBJ_ANY
+	ObjectBad               = C.GIT_OBJ_BAD
+	ObjectCommit            = C.GIT_OBJ_COMMIT
+	ObjectTree              = C.GIT_OBJ_TREE
+	ObjectBlob              = C.GIT_OBJ_BLOB
+	ObjectTag               = C.GIT_OBJ_TAG
 )
 
 type Object interface {
@@ -28,8 +28,8 @@ type gitObject struct {
 	ptr *C.git_object
 }
 
-func (t ObjectType) String() (string) {
-	switch (t) {
+func (t ObjectType) String() string {
+	switch t {
 	case ObjectAny:
 		return "Any"
 	case ObjectBad:
diff --git a/odb.go b/odb.go
index eaa7872..d5a54ac 100644
--- a/odb.go
+++ b/odb.go
@@ -8,9 +8,9 @@ extern int _go_git_odb_foreach(git_odb *db, void *payload);
 */
 import "C"
 import (
-	"unsafe"
 	"reflect"
 	"runtime"
+	"unsafe"
 )
 
 type Odb struct {
@@ -25,6 +25,10 @@ func (v *Odb) Exists(oid *Oid) bool {
 func (v *Odb) Write(data []byte, otype ObjectType) (oid *Oid, err error) {
 	oid = new(Oid)
 	hdr := (*reflect.SliceHeader)(unsafe.Pointer(&data))
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_odb_write(oid.toC(), v.ptr, unsafe.Pointer(hdr.Data), C.size_t(hdr.Len), C.git_otype(otype))
 
 	if ret < 0 {
@@ -36,6 +40,10 @@ func (v *Odb) Write(data []byte, otype ObjectType) (oid *Oid, err error) {
 
 func (v *Odb) Read(oid *Oid) (obj *OdbObject, err error) {
 	obj = new(OdbObject)
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_odb_read(&obj.ptr, v.ptr, oid.toC())
 	if ret < 0 {
 		return nil, LastError()
@@ -55,9 +63,9 @@ func odbForEachCb(id *C.git_oid, payload unsafe.Pointer) int {
 	select {
 	case ch <- oid:
 	case <-ch:
-			return -1
+		return -1
 	}
-	return 0;
+	return 0
 }
 
 func (v *Odb) forEachWrap(ch chan *Oid) {
@@ -161,7 +169,7 @@ func (stream *OdbReadStream) Free() {
 
 type OdbWriteStream struct {
 	ptr *C.git_odb_stream
-	Id Oid
+	Id  Oid
 }
 
 // Write writes to the stream
diff --git a/odb_test.go b/odb_test.go
index 3c7624c..fded782 100644
--- a/odb_test.go
+++ b/odb_test.go
@@ -32,4 +32,4 @@ func TestOdbStream(t *testing.T) {
 	if stream.Id.Cmp(expectedId) != 0 {
 		t.Fatal("Wrong data written")
 	}
-}
\ No newline at end of file
+}
diff --git a/packbuilder.go b/packbuilder.go
index c57b0d4..e628bd1 100644
--- a/packbuilder.go
+++ b/packbuilder.go
@@ -22,6 +22,10 @@ type Packbuilder struct {
 
 func (repo *Repository) NewPackbuilder() (*Packbuilder, error) {
 	builder := &Packbuilder{}
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_packbuilder_new(&builder.ptr, repo.ptr)
 	if ret != 0 {
 		return nil, LastError()
@@ -38,6 +42,10 @@ func (pb *Packbuilder) Free() {
 func (pb *Packbuilder) Insert(id *Oid, name string) error {
 	cname := C.CString(name)
 	defer C.free(unsafe.Pointer(cname))
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_packbuilder_insert(pb.ptr, id.toC(), cname)
 	if ret != 0 {
 		return LastError()
@@ -46,6 +54,9 @@ func (pb *Packbuilder) Insert(id *Oid, name string) error {
 }
 
 func (pb *Packbuilder) InsertCommit(id *Oid) error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_packbuilder_insert_commit(pb.ptr, id.toC())
 	if ret != 0 {
 		return LastError()
@@ -54,6 +65,9 @@ func (pb *Packbuilder) InsertCommit(id *Oid) error {
 }
 
 func (pb *Packbuilder) InsertTree(id *Oid) error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_packbuilder_insert_tree(pb.ptr, id.toC())
 	if ret != 0 {
 		return LastError()
@@ -68,6 +82,10 @@ func (pb *Packbuilder) ObjectCount() uint32 {
 func (pb *Packbuilder) WriteToFile(name string, mode os.FileMode) error {
 	cname := C.CString(name)
 	defer C.free(unsafe.Pointer(cname))
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_packbuilder_write(pb.ptr, cname, C.uint(mode.Perm()), nil, nil)
 	if ret != 0 {
 		return LastError()
@@ -92,7 +110,7 @@ func (pb *Packbuilder) Written() uint32 {
 }
 
 type packbuilderCbData struct {
-	ch chan<- []byte
+	ch   chan<- []byte
 	stop <-chan bool
 }
 
@@ -104,7 +122,7 @@ func packbuilderForEachCb(buf unsafe.Pointer, size C.size_t, payload unsafe.Poin
 
 	slice := C.GoBytes(buf, C.int(size))
 	select {
-	case <- stop:
+	case <-stop:
 		return -1
 	case ch <- slice:
 	}
diff --git a/reference.go b/reference.go
index 8060146..e067aa7 100644
--- a/reference.go
+++ b/reference.go
@@ -40,6 +40,9 @@ func (v *Reference) SetSymbolicTarget(target string, sig *Signature, msg string)
 	cmsg := C.CString(msg)
 	defer C.free(unsafe.Pointer(cmsg))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_reference_symbolic_set_target(&ptr, v.ptr, ctarget, csig, cmsg)
 	if ret < 0 {
 		return nil, LastError()
@@ -68,6 +71,9 @@ func (v *Reference) SetTarget(target *Oid, sig *Signature, msg string) (*Referen
 func (v *Reference) Resolve() (*Reference, error) {
 	var ptr *C.git_reference
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_reference_resolve(&ptr, v.ptr)
 	if ret < 0 {
 		return nil, LastError()
@@ -76,12 +82,18 @@ func (v *Reference) Resolve() (*Reference, error) {
 	return newReferenceFromC(ptr), nil
 }
 
-func (v *Reference) Rename(name string, force bool) (*Reference, error) {
+func (v *Reference) Rename(name string, force bool, logMsg string) (*Reference, error) {
 	var ptr *C.git_reference
 	cname := C.CString(name)
 	defer C.free(unsafe.Pointer(cname))
 
-	ret := C.git_reference_rename(&ptr, v.ptr, cname, cbool(force))
+	cLogMsg := C.CString(logMsg)
+	defer C.free(unsafe.Pointer(cLogMsg))
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	ret := C.git_reference_rename(&ptr, v.ptr, cname, cbool(force), nil, cLogMsg)
 
 	if ret < 0 {
 		return nil, LastError()
@@ -104,6 +116,9 @@ func (v *Reference) SymbolicTarget() string {
 }
 
 func (v *Reference) Delete() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_reference_delete(v.ptr)
 
 	if ret < 0 {
@@ -134,6 +149,10 @@ type ReferenceIterator struct {
 // NewReferenceIterator creates a new iterator over reference names
 func (repo *Repository) NewReferenceIterator() (*ReferenceIterator, error) {
 	var ptr *C.git_reference_iterator
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_reference_iterator_new(&ptr, repo.ptr)
 	if ret < 0 {
 		return nil, LastError()
@@ -151,6 +170,10 @@ func (repo *Repository) NewReferenceIteratorGlob(glob string) (*ReferenceIterato
 	cstr := C.CString(glob)
 	defer C.free(unsafe.Pointer(cstr))
 	var ptr *C.git_reference_iterator
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_reference_iterator_glob_new(&ptr, repo.ptr, cstr)
 	if ret < 0 {
 		return nil, LastError()
@@ -165,6 +188,10 @@ func (repo *Repository) NewReferenceIteratorGlob(glob string) (*ReferenceIterato
 // the returned error is git.ErrIterOver
 func (v *ReferenceIterator) NextName() (string, error) {
 	var ptr *C.char
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_reference_next_name(&ptr, v.ptr)
 	if ret == ITEROVER {
 		return "", ErrIterOver
diff --git a/reference_test.go b/reference_test.go
index ab62522..dd0c75d 100644
--- a/reference_test.go
+++ b/reference_test.go
@@ -52,7 +52,7 @@ func TestRefModification(t *testing.T) {
 		t.Fatalf("Wrong ref target")
 	}
 
-	_, err = tag.Rename("refs/tags/renamed", false)
+	_, err = tag.Rename("refs/tags/renamed", false, "")
 	checkFatal(t, err)
 	tag, err = repo.LookupReference("refs/tags/renamed")
 	checkFatal(t, err)
diff --git a/repository.go b/repository.go
index 31a2d05..27f200e 100644
--- a/repository.go
+++ b/repository.go
@@ -21,6 +21,9 @@ func OpenRepository(path string) (*Repository, error) {
 	cpath := C.CString(path)
 	defer C.free(unsafe.Pointer(cpath))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_repository_open(&repo.ptr, cpath)
 	if ret < 0 {
 		return nil, LastError()
@@ -36,6 +39,9 @@ func InitRepository(path string, isbare bool) (*Repository, error) {
 	cpath := C.CString(path)
 	defer C.free(unsafe.Pointer(cpath))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_repository_init(&repo.ptr, cpath, ucbool(isbare))
 	if ret < 0 {
 		return nil, LastError()
@@ -53,16 +59,24 @@ func (v *Repository) Free() {
 func (v *Repository) Config() (*Config, error) {
 	config := new(Config)
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_repository_config(&config.ptr, v.ptr)
 	if ret < 0 {
 		return nil, LastError()
 	}
 
+	runtime.SetFinalizer(config, (*Config).Free)
 	return config, nil
 }
 
 func (v *Repository) Index() (*Index, error) {
 	var ptr *C.git_index
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_repository_index(&ptr, v.ptr)
 	if ret < 0 {
 		return nil, LastError()
@@ -73,6 +87,10 @@ func (v *Repository) Index() (*Index, error) {
 
 func (v *Repository) lookupType(oid *Oid, t ObjectType) (Object, error) {
 	var ptr *C.git_object
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_object_lookup(&ptr, v.ptr, oid.toC(), C.git_otype(t))
 	if ret < 0 {
 		return nil, LastError()
@@ -117,6 +135,9 @@ func (v *Repository) LookupReference(name string) (*Reference, error) {
 	defer C.free(unsafe.Pointer(cname))
 	var ptr *C.git_reference
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ecode := C.git_reference_lookup(&ptr, v.ptr, cname)
 	if ecode < 0 {
 		return nil, LastError()
@@ -137,6 +158,9 @@ func (v *Repository) CreateReference(name string, oid *Oid, force bool, sig *Sig
 
 	var ptr *C.git_reference
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ecode := C.git_reference_create(&ptr, v.ptr, cname, oid.toC(), cbool(force), csig, cmsg)
 	if ecode < 0 {
 		return nil, LastError()
@@ -158,6 +182,9 @@ func (v *Repository) CreateSymbolicReference(name, target string, force bool, si
 	cmsg := C.CString(msg)
 	defer C.free(unsafe.Pointer(cmsg))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	var ptr *C.git_reference
 
 	ecode := C.git_reference_symbolic_create(&ptr, v.ptr, cname, ctarget, cbool(force), csig, cmsg)
@@ -170,6 +197,10 @@ func (v *Repository) CreateSymbolicReference(name, target string, force bool, si
 
 func (v *Repository) Walk() (*RevWalk, error) {
 	walk := new(RevWalk)
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ecode := C.git_revwalk_new(&walk.ptr, v.ptr)
 	if ecode < 0 {
 		return nil, LastError()
@@ -210,10 +241,13 @@ func (v *Repository) CreateCommit(
 	committerSig := committer.toC()
 	defer C.git_signature_free(committerSig)
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_commit_create(
 		oid.toC(), v.ptr, cref,
 		authorSig, committerSig,
-		nil, cmsg, tree.ptr, C.int(nparents), parentsarg)
+		nil, cmsg, tree.ptr, C.size_t(nparents), parentsarg)
 
 	if ret < 0 {
 		return nil, LastError()
@@ -229,6 +263,10 @@ func (v *Odb) Free() {
 
 func (v *Repository) Odb() (odb *Odb, err error) {
 	odb = new(Odb)
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	if ret := C.git_repository_odb(&odb.ptr, v.ptr); ret < 0 {
 		return nil, LastError()
 	}
@@ -253,6 +291,9 @@ func (repo *Repository) SetWorkdir(workdir string, updateGitlink bool) error {
 	cstr := C.CString(workdir)
 	defer C.free(unsafe.Pointer(cstr))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	if C.git_repository_set_workdir(repo.ptr, cstr, cbool(updateGitlink)) < 0 {
 		return LastError()
 	}
@@ -261,9 +302,14 @@ func (repo *Repository) SetWorkdir(workdir string, updateGitlink bool) error {
 
 func (v *Repository) TreeBuilder() (*TreeBuilder, error) {
 	bld := new(TreeBuilder)
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	if ret := C.git_treebuilder_create(&bld.ptr, nil); ret < 0 {
 		return nil, LastError()
 	}
+	runtime.SetFinalizer(bld, (*TreeBuilder).Free)
 
 	bld.repo = v
 	return bld, nil
@@ -274,6 +320,10 @@ func (v *Repository) RevparseSingle(spec string) (Object, error) {
 	defer C.free(unsafe.Pointer(cspec))
 
 	var ptr *C.git_object
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ecode := C.git_revparse_single(&ptr, v.ptr, cspec)
 	if ecode < 0 {
 		return nil, LastError()
diff --git a/submodule.go b/submodule.go
index 903d784..cf422d2 100644
--- a/submodule.go
+++ b/submodule.go
@@ -8,6 +8,7 @@ extern int _go_git_visit_submodule(git_repository *repo, void *fct);
 */
 import "C"
 import (
+	"runtime"
 	"unsafe"
 )
 
@@ -58,7 +59,8 @@ const (
 type SubmoduleRecurse int
 
 const (
-	SubmoduleRecurseNo       SubmoduleRecurse = C.GIT_SUBMODULE_RECURSE_NO
+	SubmoduleRecurseReset    SubmoduleRecurse = C.GIT_SUBMODULE_RECURSE_RESET
+	SubmoduleRecurseNo                        = C.GIT_SUBMODULE_RECURSE_NO
 	SubmoduleRecurseYes                       = C.GIT_SUBMODULE_RECURSE_YES
 	SubmoduleRecurseOndemand                  = C.GIT_SUBMODULE_RECURSE_ONDEMAND
 )
@@ -74,6 +76,10 @@ func (repo *Repository) LookupSubmodule(name string) (*Submodule, error) {
 	defer C.free(unsafe.Pointer(cname))
 
 	sub := new(Submodule)
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_lookup(&sub.ptr, repo.ptr, cname)
 	if ret < 0 {
 		return nil, LastError()
@@ -92,6 +98,9 @@ func SubmoduleVisitor(csub unsafe.Pointer, name string, cfct unsafe.Pointer) int
 }
 
 func (repo *Repository) ForeachSubmodule(cbk SubmoduleCbk) error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C._go_git_visit_submodule(repo.ptr, unsafe.Pointer(&cbk))
 	if ret < 0 {
 		return LastError()
@@ -106,6 +115,10 @@ func (repo *Repository) AddSubmodule(url, path string, use_git_link bool) (*Subm
 	defer C.free(unsafe.Pointer(cpath))
 
 	sub := new(Submodule)
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_add_setup(&sub.ptr, repo.ptr, curl, cpath, cbool(use_git_link))
 	if ret < 0 {
 		return nil, LastError()
@@ -114,6 +127,9 @@ func (repo *Repository) AddSubmodule(url, path string, use_git_link bool) (*Subm
 }
 
 func (sub *Submodule) FinalizeAdd() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_add_finalize(sub.ptr)
 	if ret < 0 {
 		return LastError()
@@ -122,6 +138,9 @@ func (sub *Submodule) FinalizeAdd() error {
 }
 
 func (sub *Submodule) AddToIndex(write_index bool) error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_add_to_index(sub.ptr, cbool(write_index))
 	if ret < 0 {
 		return LastError()
@@ -130,6 +149,9 @@ func (sub *Submodule) AddToIndex(write_index bool) error {
 }
 
 func (sub *Submodule) Save() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_save(sub.ptr)
 	if ret < 0 {
 		return LastError()
@@ -162,6 +184,9 @@ func (sub *Submodule) SetUrl(url string) error {
 	curl := C.CString(url)
 	defer C.free(unsafe.Pointer(curl))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_set_url(sub.ptr, curl)
 	if ret < 0 {
 		return LastError()
@@ -229,6 +254,9 @@ func (sub *Submodule) SetFetchRecurseSubmodules(recurse SubmoduleRecurse) error
 }
 
 func (sub *Submodule) Init(overwrite bool) error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_init(sub.ptr, cbool(overwrite))
 	if ret < 0 {
 		return LastError()
@@ -237,6 +265,9 @@ func (sub *Submodule) Init(overwrite bool) error {
 }
 
 func (sub *Submodule) Sync() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_sync(sub.ptr)
 	if ret < 0 {
 		return LastError()
@@ -246,6 +277,10 @@ func (sub *Submodule) Sync() error {
 
 func (sub *Submodule) Open() (*Repository, error) {
 	repo := new(Repository)
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_open(&repo.ptr, sub.ptr)
 	if ret < 0 {
 		return nil, LastError()
@@ -254,6 +289,9 @@ func (sub *Submodule) Open() (*Repository, error) {
 }
 
 func (sub *Submodule) Reload() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_reload(sub.ptr)
 	if ret < 0 {
 		return LastError()
@@ -262,6 +300,9 @@ func (sub *Submodule) Reload() error {
 }
 
 func (repo *Repository) ReloadAllSubmodules() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_submodule_reload_all(repo.ptr)
 	if ret < 0 {
 		return LastError()
diff --git a/tree.go b/tree.go
index 3abd31c..2e7eae6 100644
--- a/tree.go
+++ b/tree.go
@@ -14,13 +14,14 @@ import (
 )
 
 type Filemode int
+
 const (
-	FilemodeNew   Filemode = C.GIT_FILEMODE_NEW
-	FilemodeTree           = C.GIT_FILEMODE_TREE
-	FilemodeBlob           = C.GIT_FILEMODE_BLOB
-	FilemodeBlobExecutable = C.GIT_FILEMODE_BLOB_EXECUTABLE
-	FilemodeLink           = C.GIT_FILEMODE_LINK
-	FilemodeCommit         = C.GIT_FILEMODE_COMMIT
+	FilemodeNew            Filemode = C.GIT_FILEMODE_NEW
+	FilemodeTree                    = C.GIT_FILEMODE_TREE
+	FilemodeBlob                    = C.GIT_FILEMODE_BLOB
+	FilemodeBlobExecutable          = C.GIT_FILEMODE_BLOB_EXECUTABLE
+	FilemodeLink                    = C.GIT_FILEMODE_LINK
+	FilemodeCommit                  = C.GIT_FILEMODE_COMMIT
 )
 
 type Tree struct {
@@ -28,9 +29,9 @@ type Tree struct {
 }
 
 type TreeEntry struct {
-	Name string
-	Id  *Oid
-	Type ObjectType
+	Name     string
+	Id       *Oid
+	Type     ObjectType
 	Filemode int
 }
 
@@ -62,6 +63,9 @@ func (t Tree) EntryByPath(path string) (*TreeEntry, error) {
 	defer C.free(unsafe.Pointer(cpath))
 	var entry *C.git_tree_entry
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_tree_entry_bypath(&entry, t.ptr, cpath)
 	if ret < 0 {
 		return nil, LastError()
@@ -96,6 +100,9 @@ func CallbackGitTreeWalk(_root unsafe.Pointer, _entry unsafe.Pointer, ptr unsafe
 }
 
 func (t Tree) Walk(callback TreeWalkCallback) error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	err := C._go_git_treewalk(
 		t.ptr,
 		C.GIT_TREEWALK_PRE,
@@ -110,7 +117,7 @@ func (t Tree) Walk(callback TreeWalkCallback) error {
 }
 
 type TreeBuilder struct {
-	ptr *C.git_treebuilder
+	ptr  *C.git_treebuilder
 	repo *Repository
 }
 
@@ -119,10 +126,13 @@ func (v *TreeBuilder) Free() {
 	C.git_treebuilder_free(v.ptr)
 }
 
-func (v *TreeBuilder) Insert(filename string, id *Oid, filemode int) (error) {
+func (v *TreeBuilder) Insert(filename string, id *Oid, filemode int) error {
 	cfilename := C.CString(filename)
 	defer C.free(unsafe.Pointer(cfilename))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	err := C.git_treebuilder_insert(nil, v.ptr, cfilename, id.toC(), C.git_filemode_t(filemode))
 	if err < 0 {
 		return LastError()
@@ -133,6 +143,10 @@ func (v *TreeBuilder) Insert(filename string, id *Oid, filemode int) (error) {
 
 func (v *TreeBuilder) Write() (*Oid, error) {
 	oid := new(Oid)
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	err := C.git_treebuilder_write(oid.toC(), v.repo.ptr, v.ptr)
 
 	if err < 0 {
diff --git a/walk.go b/walk.go
index 9fc4094..6f702f1 100644
--- a/walk.go
+++ b/walk.go
@@ -8,16 +8,18 @@ import "C"
 
 import (
 	"io"
+	"runtime"
 )
 
 // RevWalk
 
 type SortType uint
+
 const (
-	SortNone SortType = C.GIT_SORT_NONE
-	SortTopological   = C.GIT_SORT_TOPOLOGICAL
-	SortTime          = C.GIT_SORT_TIME
-	SortReverse       = C.GIT_SORT_REVERSE
+	SortNone        SortType = C.GIT_SORT_NONE
+	SortTopological          = C.GIT_SORT_TOPOLOGICAL
+	SortTime                 = C.GIT_SORT_TIME
+	SortReverse              = C.GIT_SORT_REVERSE
 )
 
 type RevWalk struct {
@@ -34,6 +36,9 @@ func (v *RevWalk) Push(id *Oid) {
 }
 
 func (v *RevWalk) PushHead() (err error) {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ecode := C.git_revwalk_push_head(v.ptr)
 	if ecode < 0 {
 		err = LastError()
@@ -43,6 +48,9 @@ func (v *RevWalk) PushHead() (err error) {
 }
 
 func (v *RevWalk) Next(oid *Oid) (err error) {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	ret := C.git_revwalk_next(oid.toC(), v.ptr)
 	switch {
 	case ret == ITEROVER: