diff --git a/branch.go b/branch.go
index 54b01fb..22b767e 100644
--- a/branch.go
+++ b/branch.go
@@ -96,7 +96,10 @@ func (repo *Repository) CreateBranch(branchName string, target *Commit, force bo
 	cBranchName := C.CString(branchName)
 	cForce := cbool(force)
 
-	cSignature := signature.toC()
+	cSignature, err := signature.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.git_signature_free(cSignature)
 
 	var cmsg *C.char
@@ -133,7 +136,10 @@ func (b *Branch) Move(newBranchName string, force bool, signature *Signature, ms
 	cNewBranchName := C.CString(newBranchName)
 	cForce := cbool(force)
 
-	cSignature := signature.toC()
+	cSignature, err := signature.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.git_signature_free(cSignature)
 
 	var cmsg *C.char
diff --git a/checkout.go b/checkout.go
index 06d010c..6eb6098 100644
--- a/checkout.go
+++ b/checkout.go
@@ -20,10 +20,10 @@ const (
 	CheckoutAllowConflicts            CheckoutStrategy = C.GIT_CHECKOUT_ALLOW_CONFLICTS              // Allow checkout to make safe updates even if conflicts are found
 	CheckoutRemoveUntracked           CheckoutStrategy = C.GIT_CHECKOUT_REMOVE_UNTRACKED             // Remove untracked files not in index (that are not ignored)
 	CheckoutRemoveIgnored             CheckoutStrategy = C.GIT_CHECKOUT_REMOVE_IGNORED               // Remove ignored files not in index
-	CheckotUpdateOnly                 CheckoutStrategy = C.GIT_CHECKOUT_UPDATE_ONLY                  // Only update existing files, don't create new ones
+	CheckoutUpdateOnly                CheckoutStrategy = C.GIT_CHECKOUT_UPDATE_ONLY                  // Only update existing files, don't create new ones
 	CheckoutDontUpdateIndex           CheckoutStrategy = C.GIT_CHECKOUT_DONT_UPDATE_INDEX            // Normally checkout updates index entries as it goes; this stops that
 	CheckoutNoRefresh                 CheckoutStrategy = C.GIT_CHECKOUT_NO_REFRESH                   // Don't refresh index/config/etc before doing checkout
-	CheckooutDisablePathspecMatch     CheckoutStrategy = C.GIT_CHECKOUT_DISABLE_PATHSPEC_MATCH       // Treat pathspec as simple list of exact match file paths
+	CheckoutDisablePathspecMatch      CheckoutStrategy = C.GIT_CHECKOUT_DISABLE_PATHSPEC_MATCH       // Treat pathspec as simple list of exact match file paths
 	CheckoutSkipUnmerged              CheckoutStrategy = C.GIT_CHECKOUT_SKIP_UNMERGED                // Allow checkout to skip unmerged files (NOT IMPLEMENTED)
 	CheckoutUserOurs                  CheckoutStrategy = C.GIT_CHECKOUT_USE_OURS                     // For unmerged files, checkout stage 2 from index (NOT IMPLEMENTED)
 	CheckoutUseTheirs                 CheckoutStrategy = C.GIT_CHECKOUT_USE_THEIRS                   // For unmerged files, checkout stage 3 from index (NOT IMPLEMENTED)
@@ -40,6 +40,19 @@ type CheckoutOpts struct {
 	TargetDirectory string           // Alternative checkout path to workdir
 }
 
+func checkoutOptionsFromC(c *C.git_checkout_options) CheckoutOpts {
+	opts := CheckoutOpts{}
+	opts.Strategy = CheckoutStrategy(c.checkout_strategy)
+	opts.DisableFilters = c.disable_filters != 0
+	opts.DirMode = os.FileMode(c.dir_mode)
+	opts.FileMode = os.FileMode(c.file_mode)
+	opts.FileOpenFlags = int(c.file_open_flags)
+	if c.target_directory != nil {
+		opts.TargetDirectory = C.GoString(c.target_directory)
+	}
+	return opts
+}
+
 func (opts *CheckoutOpts) toC() *C.git_checkout_options {
 	if opts == nil {
 		return nil
diff --git a/cherrypick.go b/cherrypick.go
new file mode 100644
index 0000000..afc1b7e
--- /dev/null
+++ b/cherrypick.go
@@ -0,0 +1,73 @@
+package git
+
+/*
+#include <git2.h>
+*/
+import "C"
+import (
+	"runtime"
+)
+
+type CherrypickOptions struct {
+	Version      uint
+	Mainline     uint
+	MergeOpts    MergeOptions
+	CheckoutOpts CheckoutOpts
+}
+
+func cherrypickOptionsFromC(c *C.git_cherrypick_options) CherrypickOptions {
+	opts := CherrypickOptions{
+		Version:      uint(c.version),
+		Mainline:     uint(c.mainline),
+		MergeOpts:    mergeOptionsFromC(&c.merge_opts),
+		CheckoutOpts: checkoutOptionsFromC(&c.checkout_opts),
+	}
+	return opts
+}
+
+func (opts *CherrypickOptions) toC() *C.git_cherrypick_options {
+	if opts == nil {
+		return nil
+	}
+	c := C.git_cherrypick_options{}
+	c.version = C.uint(opts.Version)
+	c.mainline = C.uint(opts.Mainline)
+	c.merge_opts = *opts.MergeOpts.toC()
+	c.checkout_opts = *opts.CheckoutOpts.toC()
+	return &c
+}
+
+func freeCherrypickOpts(ptr *C.git_cherrypick_options) {
+	if ptr == nil {
+		return
+	}
+	freeCheckoutOpts(&ptr.checkout_opts)
+}
+
+func DefaultCherrypickOptions() (CherrypickOptions, error) {
+	c := C.git_cherrypick_options{}
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	ecode := C.git_cherrypick_init_options(&c, C.GIT_CHERRYPICK_OPTIONS_VERSION)
+	if ecode < 0 {
+		return CherrypickOptions{}, MakeGitError(ecode)
+	}
+	defer freeCherrypickOpts(&c)
+	return cherrypickOptionsFromC(&c), nil
+}
+
+func (v *Repository) Cherrypick(commit *Commit, opts CherrypickOptions) error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	cOpts := opts.toC()
+	defer freeCherrypickOpts(cOpts)
+
+	ecode := C.git_cherrypick(v.ptr, commit.cast_ptr, cOpts)
+	if ecode < 0 {
+		return MakeGitError(ecode)
+	}
+	return nil
+}
diff --git a/cherrypick_test.go b/cherrypick_test.go
new file mode 100644
index 0000000..f06dbdd
--- /dev/null
+++ b/cherrypick_test.go
@@ -0,0 +1,83 @@
+package git
+
+import (
+	"io/ioutil"
+	"testing"
+)
+
+func checkout(t *testing.T, repo *Repository, commit *Commit) {
+	tree, err := commit.Tree()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = repo.CheckoutTree(tree, &CheckoutOpts{Strategy: CheckoutSafe})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = repo.SetHeadDetached(commit.Id(), commit.Author(), "checkout")
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+const content = "Herro, Worrd!"
+
+func readReadme(t *testing.T, repo *Repository) string {
+	bytes, err := ioutil.ReadFile(pathInRepo(repo, "README"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	return string(bytes)
+}
+
+func TestCherrypick(t *testing.T) {
+	repo := createTestRepo(t)
+	c1, _ := seedTestRepo(t, repo)
+	c2, _ := updateReadme(t, repo, content)
+
+	commit1, err := repo.LookupCommit(c1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	commit2, err := repo.LookupCommit(c2)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	checkout(t, repo, commit1)
+
+	if readReadme(t, repo) == content {
+		t.Fatalf("README has wrong content after checking out initial commit")
+	}
+
+	opts, err := DefaultCherrypickOptions()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = repo.Cherrypick(commit2, opts)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if readReadme(t, repo) != content {
+		t.Fatalf("README has wrong contents after cherry-picking")
+	}
+
+	state := repo.State()
+	if state != RepositoryStateCherrypick {
+		t.Fatal("Incorrect repository state: ", state)
+	}
+
+	err = repo.StateCleanup()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	state = repo.State()
+	if state != RepositoryStateNone {
+		t.Fatal("Incorrect repository state: ", state)
+	}
+}
diff --git a/commit.go b/commit.go
index 559a1bd..57e1a77 100644
--- a/commit.go
+++ b/commit.go
@@ -9,8 +9,6 @@ import "C"
 
 import (
 	"runtime"
-	"time"
-	"unsafe"
 )
 
 // Commit
@@ -23,6 +21,10 @@ func (c Commit) Message() string {
 	return C.GoString(C.git_commit_message(c.cast_ptr))
 }
 
+func (c Commit) Summary() string {
+	return C.GoString(C.git_commit_summary(c.cast_ptr))
+}
+
 func (c Commit) Tree() (*Tree, error) {
 	var ptr *C.git_tree
 
@@ -68,49 +70,3 @@ func (c *Commit) ParentId(n uint) *Oid {
 func (c *Commit) ParentCount() uint {
 	return uint(C.git_commit_parentcount(c.cast_ptr))
 }
-
-// Signature
-
-type Signature struct {
-	Name  string
-	Email string
-	When  time.Time
-}
-
-func newSignatureFromC(sig *C.git_signature) *Signature {
-	// git stores minutes, go wants seconds
-	loc := time.FixedZone("", int(sig.when.offset)*60)
-	return &Signature{
-		C.GoString(sig.name),
-		C.GoString(sig.email),
-		time.Unix(int64(sig.when.time), 0).In(loc),
-	}
-}
-
-// the offset in mintes, which is what git wants
-func (v *Signature) Offset() int {
-	_, offset := v.When.Zone()
-	return offset / 60
-}
-
-func (sig *Signature) toC() *C.git_signature {
-
-	if sig == nil {
-		return nil
-	}
-
-	var out *C.git_signature
-
-	name := C.CString(sig.Name)
-	defer C.free(unsafe.Pointer(name))
-
-	email := C.CString(sig.Email)
-	defer C.free(unsafe.Pointer(email))
-
-	ret := C.git_signature_new(&out, name, email, C.git_time_t(sig.When.Unix()), C.int(sig.Offset()))
-	if ret < 0 {
-		return nil
-	}
-
-	return out
-}
diff --git a/git_test.go b/git_test.go
index 56adeed..b9cf0a9 100644
--- a/git_test.go
+++ b/git_test.go
@@ -57,6 +57,10 @@ func seedTestRepo(t *testing.T, repo *Repository) (*Oid, *Oid) {
 	return commitId, treeId
 }
 
+func pathInRepo(repo *Repository, name string) string {
+	return path.Join(path.Dir(path.Dir(repo.Path())), name)
+}
+
 func updateReadme(t *testing.T, repo *Repository, content string) (*Oid, *Oid) {
 	loc, err := time.LoadLocation("Europe/Berlin")
 	checkFatal(t, err)
@@ -67,7 +71,7 @@ func updateReadme(t *testing.T, repo *Repository, content string) (*Oid, *Oid) {
 	}
 
 	tmpfile := "README"
-	err = ioutil.WriteFile(path.Join(path.Dir(path.Dir(repo.Path())), tmpfile), []byte(content), 0644)
+	err = ioutil.WriteFile(pathInRepo(repo, tmpfile), []byte(content), 0644)
 	checkFatal(t, err)
 
 	idx, err := repo.Index()
diff --git a/object.go b/object.go
index 7428e0f..20cee85 100644
--- a/object.go
+++ b/object.go
@@ -25,12 +25,12 @@ type Object interface {
 }
 
 type gitObject struct {
-	ptr *C.git_object
+	ptr  *C.git_object
 	repo *Repository
 }
 
-func (t ObjectType) String() (string) {
-	switch (t) {
+func (t ObjectType) String() string {
+	switch t {
 	case ObjectAny:
 		return "Any"
 	case ObjectBad:
@@ -71,7 +71,7 @@ func (o *gitObject) Free() {
 
 func allocObject(cobj *C.git_object, repo *Repository) Object {
 	obj := gitObject{
-		ptr: cobj,
+		ptr:  cobj,
 		repo: repo,
 	}
 
diff --git a/odb.go b/odb.go
index 19bb71c..ba03860 100644
--- a/odb.go
+++ b/odb.go
@@ -94,7 +94,7 @@ type OdbForEachCallback func(id *Oid) error
 
 type foreachData struct {
 	callback OdbForEachCallback
-	err error
+	err      error
 }
 
 //export odbForEachCb
@@ -111,9 +111,9 @@ func odbForEachCb(id *C.git_oid, payload unsafe.Pointer) int {
 }
 
 func (v *Odb) ForEach(callback OdbForEachCallback) error {
-	data := foreachData {
+	data := foreachData{
 		callback: callback,
-		err: nil,
+		err:      nil,
 	}
 
 	runtime.LockOSThread()
@@ -138,7 +138,7 @@ func (v *Odb) Hash(data []byte, otype ObjectType) (oid *Oid, err error) {
 	runtime.LockOSThread()
 	defer runtime.UnlockOSThread()
 
-	ret := C.git_odb_hash(oid.toC(), ptr, C.size_t(header.Len), C.git_otype(otype));
+	ret := C.git_odb_hash(oid.toC(), ptr, C.size_t(header.Len), C.git_otype(otype))
 	if ret < 0 {
 		return nil, MakeGitError(ret)
 	}
diff --git a/odb_test.go b/odb_test.go
index 14a3658..5e6b7ff 100644
--- a/odb_test.go
+++ b/odb_test.go
@@ -1,9 +1,9 @@
 package git
 
 import (
+	"errors"
 	"io"
 	"os"
-	"errors"
 	"testing"
 )
 
@@ -37,7 +37,7 @@ func TestOdbStream(t *testing.T) {
 
 func TestOdbHash(t *testing.T) {
 
-    repo := createTestRepo(t)
+	repo := createTestRepo(t)
 	defer os.RemoveAll(repo.Workdir())
 	_, _ = seedTestRepo(t, repo)
 
diff --git a/packbuilder.go b/packbuilder.go
index 7c94926..54a8390 100644
--- a/packbuilder.go
+++ b/packbuilder.go
@@ -128,7 +128,7 @@ func packbuilderForEachCb(buf unsafe.Pointer, size C.size_t, payload unsafe.Poin
 func (pb *Packbuilder) ForEach(callback PackbuilderForeachCallback) error {
 	data := packbuilderCbData{
 		callback: callback,
-		err: nil,
+		err:      nil,
 	}
 
 	runtime.LockOSThread()
diff --git a/reference.go b/reference.go
index 46436a6..ef12d0b 100644
--- a/reference.go
+++ b/reference.go
@@ -36,7 +36,10 @@ func (v *Reference) SetSymbolicTarget(target string, sig *Signature, msg string)
 	runtime.LockOSThread()
 	defer runtime.UnlockOSThread()
 
-	csig := sig.toC()
+	csig, err := sig.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.free(unsafe.Pointer(csig))
 
 	var cmsg *C.char
@@ -61,7 +64,10 @@ func (v *Reference) SetTarget(target *Oid, sig *Signature, msg string) (*Referen
 	runtime.LockOSThread()
 	defer runtime.UnlockOSThread()
 
-	csig := sig.toC()
+	csig, err := sig.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.free(unsafe.Pointer(csig))
 
 	var cmsg *C.char
@@ -99,7 +105,10 @@ func (v *Reference) Rename(name string, force bool, sig *Signature, msg string)
 	cname := C.CString(name)
 	defer C.free(unsafe.Pointer(cname))
 
-	csig := sig.toC()
+	csig, err := sig.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.free(unsafe.Pointer(csig))
 
 	var cmsg *C.char
diff --git a/remote.go b/remote.go
index 2684c20..84750d3 100644
--- a/remote.go
+++ b/remote.go
@@ -604,7 +604,10 @@ func (o *Remote) Fetch(refspecs []string, sig *Signature, msg string) error {
 
 	var csig *C.git_signature = nil
 	if sig != nil {
-		csig = sig.toC()
+		csig, err := sig.toC()
+		if err != nil {
+			return err
+		}
 		defer C.free(unsafe.Pointer(csig))
 	}
 
@@ -696,7 +699,10 @@ func (o *Remote) Ls(filterRefs ...string) ([]RemoteHead, error) {
 func (o *Remote) Push(refspecs []string, opts *PushOptions, sig *Signature, msg string) error {
 	var csig *C.git_signature = nil
 	if sig != nil {
-		csig = sig.toC()
+		csig, err := sig.toC()
+		if err != nil {
+			return err
+		}
 		defer C.free(unsafe.Pointer(csig))
 	}
 
diff --git a/repository.go b/repository.go
index 7760c3a..7fac277 100644
--- a/repository.go
+++ b/repository.go
@@ -210,7 +210,10 @@ func (v *Repository) SetHead(refname string, sig *Signature, msg string) error {
 	cname := C.CString(refname)
 	defer C.free(unsafe.Pointer(cname))
 
-	csig := sig.toC()
+	csig, err := sig.toC()
+	if err != nil {
+		return err
+	}
 	defer C.free(unsafe.Pointer(csig))
 
 	var cmsg *C.char
@@ -230,7 +233,10 @@ func (v *Repository) SetHead(refname string, sig *Signature, msg string) error {
 }
 
 func (v *Repository) SetHeadDetached(id *Oid, sig *Signature, msg string) error {
-	csig := sig.toC()
+	csig, err := sig.toC()
+	if err != nil {
+		return err
+	}
 	defer C.free(unsafe.Pointer(csig))
 
 	var cmsg *C.char
@@ -253,7 +259,10 @@ func (v *Repository) CreateReference(name string, id *Oid, force bool, sig *Sign
 	cname := C.CString(name)
 	defer C.free(unsafe.Pointer(cname))
 
-	csig := sig.toC()
+	csig, err := sig.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.free(unsafe.Pointer(csig))
 
 	var cmsg *C.char
@@ -284,7 +293,10 @@ func (v *Repository) CreateSymbolicReference(name, target string, force bool, si
 	ctarget := C.CString(target)
 	defer C.free(unsafe.Pointer(ctarget))
 
-	csig := sig.toC()
+	csig, err := sig.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.free(unsafe.Pointer(csig))
 
 	var cmsg *C.char
@@ -352,10 +364,16 @@ func (v *Repository) CreateCommit(
 		parentsarg = &cparents[0]
 	}
 
-	authorSig := author.toC()
+	authorSig, err := author.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.git_signature_free(authorSig)
 
-	committerSig := committer.toC()
+	committerSig, err := committer.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.git_signature_free(committerSig)
 
 	runtime.LockOSThread()
@@ -384,7 +402,10 @@ func (v *Repository) CreateTag(
 	cmessage := C.CString(message)
 	defer C.free(unsafe.Pointer(cmessage))
 
-	taggerSig := tagger.toC()
+	taggerSig, err := tagger.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.git_signature_free(taggerSig)
 
 	ctarget := commit.gitObject.ptr
@@ -546,10 +567,16 @@ func (v *Repository) CreateNote(
 		defer C.free(unsafe.Pointer(cref))
 	}
 
-	authorSig := author.toC()
+	authorSig, err := author.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.git_signature_free(authorSig)
 
-	committerSig := committer.toC()
+	committerSig, err := committer.toC()
+	if err != nil {
+		return nil, err
+	}
 	defer C.git_signature_free(committerSig)
 
 	cnote := C.CString(note)
@@ -601,10 +628,16 @@ func (v *Repository) RemoveNote(ref string, author, committer *Signature, id *Oi
 		defer C.free(unsafe.Pointer(cref))
 	}
 
-	authorSig := author.toC()
+	authorSig, err := author.toC()
+	if err != nil {
+		return err
+	}
 	defer C.git_signature_free(authorSig)
 
-	committerSig := committer.toC()
+	committerSig, err := committer.toC()
+	if err != nil {
+		return err
+	}
 	defer C.git_signature_free(committerSig)
 
 	runtime.LockOSThread()
@@ -630,3 +663,36 @@ func (v *Repository) DefaultNoteRef() (string, error) {
 
 	return C.GoString(ptr), nil
 }
+
+type RepositoryState int
+
+const (
+	RepositoryStateNone                 RepositoryState = C.GIT_REPOSITORY_STATE_NONE
+	RepositoryStateMerge                RepositoryState = C.GIT_REPOSITORY_STATE_MERGE
+	RepositoryStateRevert               RepositoryState = C.GIT_REPOSITORY_STATE_REVERT
+	RepositoryStateCherrypick           RepositoryState = C.GIT_REPOSITORY_STATE_CHERRYPICK
+	RepositoryStateBisect               RepositoryState = C.GIT_REPOSITORY_STATE_BISECT
+	RepositoryStateRebase               RepositoryState = C.GIT_REPOSITORY_STATE_REBASE
+	RepositoryStateRebaseInteractive    RepositoryState = C.GIT_REPOSITORY_STATE_REBASE_INTERACTIVE
+	RepositoryStateRebaseMerge          RepositoryState = C.GIT_REPOSITORY_STATE_REBASE_MERGE
+	RepositoryStateApplyMailbox         RepositoryState = C.GIT_REPOSITORY_STATE_APPLY_MAILBOX
+	RepositoryStateApplyMailboxOrRebase RepositoryState = C.GIT_REPOSITORY_STATE_APPLY_MAILBOX_OR_REBASE
+)
+
+func (r *Repository) State() RepositoryState {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	return RepositoryState(C.git_repository_state(r.ptr))
+}
+
+func (r *Repository) StateCleanup() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	cErr := C.git_repository_state_cleanup(r.ptr)
+	if cErr < 0 {
+		return MakeGitError(cErr)
+	}
+	return nil
+}
diff --git a/signature.go b/signature.go
new file mode 100644
index 0000000..0518387
--- /dev/null
+++ b/signature.go
@@ -0,0 +1,73 @@
+package git
+
+/*
+#include <git2.h>
+*/
+import "C"
+import (
+	"runtime"
+	"time"
+	"unsafe"
+)
+
+type Signature struct {
+	Name  string
+	Email string
+	When  time.Time
+}
+
+func newSignatureFromC(sig *C.git_signature) *Signature {
+	// git stores minutes, go wants seconds
+	loc := time.FixedZone("", int(sig.when.offset)*60)
+	return &Signature{
+		C.GoString(sig.name),
+		C.GoString(sig.email),
+		time.Unix(int64(sig.when.time), 0).In(loc),
+	}
+}
+
+// the offset in mintes, which is what git wants
+func (v *Signature) Offset() int {
+	_, offset := v.When.Zone()
+	return offset / 60
+}
+
+func (sig *Signature) toC() (*C.git_signature, error) {
+	if sig == nil {
+		return nil, nil
+	}
+
+	var out *C.git_signature
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	name := C.CString(sig.Name)
+	defer C.free(unsafe.Pointer(name))
+
+	email := C.CString(sig.Email)
+	defer C.free(unsafe.Pointer(email))
+
+	ret := C.git_signature_new(&out, name, email, C.git_time_t(sig.When.Unix()), C.int(sig.Offset()))
+	if ret < 0 {
+		return nil, MakeGitError(ret)
+	}
+
+	return out, nil
+}
+
+func (repo *Repository) DefaultSignature() (*Signature, error) {
+	var out *C.git_signature
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	cErr := C.git_signature_default(&out, repo.ptr)
+	if cErr < 0 {
+		return nil, MakeGitError(cErr)
+	}
+
+	defer C.git_signature_free(out)
+
+	return newSignatureFromC(out), nil
+}
diff --git a/status.go b/status.go
index c849aca..3f5a06d 100644
--- a/status.go
+++ b/status.go
@@ -45,7 +45,7 @@ func statusEntryFromC(statusEntry *C.git_status_entry) StatusEntry {
 		indexToWorkdir = diffDeltaFromC(statusEntry.index_to_workdir)
 	}
 
-	return StatusEntry {
+	return StatusEntry{
 		Status:         Status(statusEntry.status),
 		HeadToIndex:    headToIndex,
 		IndexToWorkdir: indexToWorkdir,
@@ -96,20 +96,20 @@ func (statusList *StatusList) EntryCount() (int, error) {
 type StatusOpt int
 
 const (
-	StatusOptIncludeUntracked           StatusOpt = C.GIT_STATUS_OPT_INCLUDE_UNTRACKED
-	StatusOptIncludeIgnored             StatusOpt = C.GIT_STATUS_OPT_INCLUDE_IGNORED
-	StatusOptIncludeUnmodified          StatusOpt = C.GIT_STATUS_OPT_INCLUDE_UNMODIFIED
-	StatusOptExcludeSubmodules          StatusOpt = C.GIT_STATUS_OPT_EXCLUDE_SUBMODULES
-	StatusOptRecurseUntrackedDirs       StatusOpt = C.GIT_STATUS_OPT_RECURSE_UNTRACKED_DIRS
-	StatusOptDisablePathspecMatch       StatusOpt = C.GIT_STATUS_OPT_DISABLE_PATHSPEC_MATCH
-	StatusOptRecurseIgnoredDirs         StatusOpt = C.GIT_STATUS_OPT_RECURSE_IGNORED_DIRS
-	StatusOptRenamesHeadToIndex         StatusOpt = C.GIT_STATUS_OPT_RENAMES_HEAD_TO_INDEX
-	StatusOptRenamesIndexToWorkdir      StatusOpt = C.GIT_STATUS_OPT_RENAMES_INDEX_TO_WORKDIR
-	StatusOptSortCaseSensitively        StatusOpt = C.GIT_STATUS_OPT_SORT_CASE_SENSITIVELY
-	StatusOptSortCaseInsensitively      StatusOpt = C.GIT_STATUS_OPT_SORT_CASE_INSENSITIVELY
-	StatusOptRenamesFromRewrites        StatusOpt = C.GIT_STATUS_OPT_RENAMES_FROM_REWRITES
-	StatusOptNoRefresh                  StatusOpt = C.GIT_STATUS_OPT_NO_REFRESH
-	StatusOptUpdateIndex                StatusOpt = C.GIT_STATUS_OPT_UPDATE_INDEX
+	StatusOptIncludeUntracked      StatusOpt = C.GIT_STATUS_OPT_INCLUDE_UNTRACKED
+	StatusOptIncludeIgnored        StatusOpt = C.GIT_STATUS_OPT_INCLUDE_IGNORED
+	StatusOptIncludeUnmodified     StatusOpt = C.GIT_STATUS_OPT_INCLUDE_UNMODIFIED
+	StatusOptExcludeSubmodules     StatusOpt = C.GIT_STATUS_OPT_EXCLUDE_SUBMODULES
+	StatusOptRecurseUntrackedDirs  StatusOpt = C.GIT_STATUS_OPT_RECURSE_UNTRACKED_DIRS
+	StatusOptDisablePathspecMatch  StatusOpt = C.GIT_STATUS_OPT_DISABLE_PATHSPEC_MATCH
+	StatusOptRecurseIgnoredDirs    StatusOpt = C.GIT_STATUS_OPT_RECURSE_IGNORED_DIRS
+	StatusOptRenamesHeadToIndex    StatusOpt = C.GIT_STATUS_OPT_RENAMES_HEAD_TO_INDEX
+	StatusOptRenamesIndexToWorkdir StatusOpt = C.GIT_STATUS_OPT_RENAMES_INDEX_TO_WORKDIR
+	StatusOptSortCaseSensitively   StatusOpt = C.GIT_STATUS_OPT_SORT_CASE_SENSITIVELY
+	StatusOptSortCaseInsensitively StatusOpt = C.GIT_STATUS_OPT_SORT_CASE_INSENSITIVELY
+	StatusOptRenamesFromRewrites   StatusOpt = C.GIT_STATUS_OPT_RENAMES_FROM_REWRITES
+	StatusOptNoRefresh             StatusOpt = C.GIT_STATUS_OPT_NO_REFRESH
+	StatusOptUpdateIndex           StatusOpt = C.GIT_STATUS_OPT_UPDATE_INDEX
 )
 
 type StatusShow int
@@ -173,7 +173,6 @@ func (v *Repository) StatusList(opts *StatusOptions) (*StatusList, error) {
 	return newStatusListFromC(ptr), nil
 }
 
-
 func (v *Repository) StatusFile(path string) (Status, error) {
 	var statusFlags C.uint
 	cPath := C.CString(path)
diff --git a/status_test.go b/status_test.go
index 4be4824..d18fca1 100644
--- a/status_test.go
+++ b/status_test.go
@@ -12,6 +12,11 @@ func TestStatusFile(t *testing.T) {
 	defer repo.Free()
 	defer os.RemoveAll(repo.Workdir())
 
+	state := repo.State()
+	if state != RepositoryStateNone {
+		t.Fatal("Incorrect repository state: ", state)
+	}
+
 	err := ioutil.WriteFile(path.Join(path.Dir(repo.Workdir()), "hello.txt"), []byte("Hello, World"), 0644)
 	checkFatal(t, err)
 
diff --git a/submodule.go b/submodule.go
index 6923c61..7c6c922 100644
--- a/submodule.go
+++ b/submodule.go
@@ -318,7 +318,10 @@ func (repo *Repository) ReloadAllSubmodules(force bool) error {
 
 func (sub *Submodule) Update(init bool, opts *SubmoduleUpdateOptions) error {
 	var copts C.git_submodule_update_options
-	populateSubmoduleUpdateOptions(&copts, opts)
+	err := populateSubmoduleUpdateOptions(&copts, opts)
+	if err != nil {
+		return err
+	}
 
 	runtime.LockOSThread()
 	defer runtime.UnlockOSThread()
@@ -331,15 +334,22 @@ func (sub *Submodule) Update(init bool, opts *SubmoduleUpdateOptions) error {
 	return nil
 }
 
-func populateSubmoduleUpdateOptions(ptr *C.git_submodule_update_options, opts *SubmoduleUpdateOptions) {
+func populateSubmoduleUpdateOptions(ptr *C.git_submodule_update_options, opts *SubmoduleUpdateOptions) error {
 	C.git_submodule_update_init_options(ptr, C.GIT_SUBMODULE_UPDATE_OPTIONS_VERSION)
 
 	if opts == nil {
-		return
+		return nil
 	}
 
 	populateCheckoutOpts(&ptr.checkout_opts, opts.CheckoutOpts)
 	populateRemoteCallbacks(&ptr.remote_callbacks, opts.RemoteCallbacks)
 	ptr.clone_checkout_strategy = C.uint(opts.CloneCheckoutStrategy)
-	ptr.signature = opts.Signature.toC()
+
+	sig, err := opts.Signature.toC()
+	if err != nil {
+		return err
+	}
+	ptr.signature = sig
+
+	return nil
 }
diff --git a/tag_test.go b/tag_test.go
index 5ebd53d..126cf6e 100644
--- a/tag_test.go
+++ b/tag_test.go
@@ -2,8 +2,8 @@ package git
 
 import (
 	"os"
-	"time"
 	"testing"
+	"time"
 )
 
 func TestCreateTag(t *testing.T) {