diff --git a/acltree/acltree.go b/acltree/acltree.go
index e8d9872e..c4d936f6 100644
--- a/acltree/acltree.go
+++ b/acltree/acltree.go
@@ -3,16 +3,9 @@ package acltree
 import (
 	"github.com/anytypeio/go-anytype-infrastructure-experiments/account"
 	"github.com/anytypeio/go-anytype-infrastructure-experiments/thread"
+	"github.com/anytypeio/go-anytype-infrastructure-experiments/util/keys"
 )
 
-func BuildACLTree(t thread.Thread, acc *account.AccountData) (ACLTree, error) {
-	// build tree from thread
-	// validate snapshot
-	// build aclstate -> filter tree
-	// return ACLTree(aclstate+)
-	return nil, nil
-}
-
 type AddResultSummary int
 
 const (
@@ -31,9 +24,128 @@ type AddResult struct {
 
 type ACLTree interface {
 	ACLState() *ACLState
-	AddChanges(changes ...*Change) (AddResult, error)
+	AddContent(changeContent *ChangeContent) (*Change, error)
+	AddChanges(changes ...*Change) (AddResult, error) // TODO: Make change as interface
 	Heads() []string
 	Iterate(func(change *Change) bool)
 	IterateFrom(string, func(change *Change) bool)
-	HasChange(change *Change)
+	HasChange(change *Change) bool
+}
+
+type aclTree struct {
+	thread      thread.Thread
+	accountData *account.AccountData
+
+	fullTree *Tree
+	aclState *ACLState
+
+	treeBuilder       *treeBuilder
+	aclTreeBuilder    *aclTreeBuilder
+	aclStateBuilder   *aclStateBuilder
+	snapshotValidator *snapshotValidator
+}
+
+func BuildACLTree(t thread.Thread, acc *account.AccountData) (ACLTree, error) {
+	decoder := keys.NewEd25519Decoder()
+	aclTreeBuilder := newACLTreeBuilder(t, decoder)
+	treeBuilder := newTreeBuilder(t, decoder)
+	snapshotValidator := newSnapshotValidator(decoder, acc)
+	aclStateBuilder := newACLStateBuilder(decoder, acc)
+
+	aclTree := &aclTree{
+		thread:            t,
+		accountData:       acc,
+		fullTree:          nil,
+		aclState:          nil,
+		treeBuilder:       treeBuilder,
+		aclTreeBuilder:    aclTreeBuilder,
+		aclStateBuilder:   aclStateBuilder,
+		snapshotValidator: snapshotValidator,
+	}
+	err := aclTree.rebuildFromThread(false)
+	if err != nil {
+		return nil, err
+	}
+
+	return aclTree, nil
+}
+
+func (a *aclTree) rebuildFromThread(fromStart bool) error {
+	var aclTree *Tree
+
+	a.treeBuilder.init()
+	a.aclTreeBuilder.init()
+
+	var err error
+	a.fullTree, err = a.treeBuilder.build(fromStart)
+	if err != nil {
+		return err
+	}
+
+	// TODO: remove this from context as this is used only to validate snapshot
+	aclTree, err = a.aclTreeBuilder.build()
+	if err != nil {
+		return err
+	}
+
+	if !fromStart {
+		err = a.snapshotValidator.init(aclTree)
+		if err != nil {
+			return err
+		}
+
+		valid, err := a.snapshotValidator.validateSnapshot(a.fullTree.root)
+		if err != nil {
+			return err
+		}
+		if !valid {
+			return a.rebuildFromThread(true)
+		}
+	}
+	err = a.aclStateBuilder.init(a.fullTree)
+	if err != nil {
+		return err
+	}
+
+	a.aclState, err = a.aclStateBuilder.build()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (a *aclTree) ACLState() *ACLState {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (a *aclTree) AddContent(changeContent *ChangeContent) (*Change, error) {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (a *aclTree) AddChanges(changes ...*Change) (AddResult, error) {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (a *aclTree) Heads() []string {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (a *aclTree) Iterate(f func(change *Change) bool) {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (a *aclTree) IterateFrom(s string, f func(change *Change) bool) {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (a *aclTree) HasChange(change *Change) bool {
+	//TODO implement me
+	panic("implement me")
 }
diff --git a/acltree/change.go b/acltree/change.go
index 7af0e511..0973d55e 100644
--- a/acltree/change.go
+++ b/acltree/change.go
@@ -2,11 +2,18 @@ package acltree
 
 import (
 	"fmt"
+	"github.com/gogo/protobuf/proto"
 
 	"github.com/anytypeio/go-anytype-infrastructure-experiments/aclchanges/pb"
 	"github.com/textileio/go-threads/crypto/symmetric"
 )
 
+type ChangeContent struct {
+	ChangesData proto.Marshaler
+	ACLData     *pb.ACLChangeACLData
+	Id          string // TODO: this is just for testing, because id should be created automatically from content
+}
+
 // Change is an abstract type for all types of changes
 type Change struct {
 	Next                    []*Change
diff --git a/acltree/tree.go b/acltree/tree.go
index 288929d2..6b4525e9 100644
--- a/acltree/tree.go
+++ b/acltree/tree.go
@@ -15,7 +15,7 @@ const (
 	Nothing
 )
 
-// TODO: consider abstracting into separate package with iterator
+// TODO: consider abstracting into separate package with iterator, remove
 type Tree struct {
 	root        *Change
 	headIds     []string