diff --git a/commit.go b/commit.go
index cacaa33..c633e2d 100644
--- a/commit.go
+++ b/commit.go
@@ -9,8 +9,8 @@ extern int _go_git_treewalk(git_tree *tree, git_treewalk_mode mode, void *ptr);
 import "C"
 
 import (
-	"unsafe"
 	"time"
+	"unsafe"
 )
 
 // Commit
@@ -48,12 +48,13 @@ 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 +86,10 @@ 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..7235716 100644
--- a/config.go
+++ b/config.go
@@ -6,6 +6,7 @@ package git
 */
 import "C"
 import (
+	"runtime"
 	"unsafe"
 )
 
@@ -66,3 +67,8 @@ 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/repository.go b/repository.go
index 34df0aa..5540a0c 100644
--- a/repository.go
+++ b/repository.go
@@ -6,8 +6,8 @@ package git
 */
 import "C"
 import (
-	"unsafe"
 	"runtime"
+	"unsafe"
 )
 
 // Repository
@@ -58,6 +58,7 @@ func (v *Repository) Config() (*Config, error) {
 		return nil, LastError()
 	}
 
+	runtime.SetFinalizer(config, (*Config).Free)
 	return config, nil
 }
 
@@ -180,7 +181,7 @@ func (v *Repository) CreateCommit(
 	var cparents []*C.git_commit = nil
 	var parentsarg **C.git_commit = nil
 
-	nparents:= len(parents)
+	nparents := len(parents)
 	if nparents > 0 {
 		cparents = make([]*C.git_commit, nparents)
 		for i, v := range parents {
@@ -226,7 +227,7 @@ func (repo *Repository) Path() string {
 	return C.GoString(C.git_repository_path(repo.ptr))
 }
 
-func (repo *Repository) IsBare() (bool) {
+func (repo *Repository) IsBare() bool {
 	return C.git_repository_is_bare(repo.ptr) != 0
 }
 
@@ -249,6 +250,7 @@ func (v *Repository) TreeBuilder() (*TreeBuilder, error) {
 	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