diff --git a/da.go b/da.go
index 175406c..63b821a 100644
--- a/da.go
+++ b/da.go
@@ -6,27 +6,19 @@ type DA interface {
 	//
 	// Error should be returned if ID is not formatted properly, there is no Blob for given ID or any other client-level
 	// error occurred (dropped connection, timeout, etc).
-	Get(id ID) (Blob, error)
+	Get(ids []ID) ([]Blob, error)
 
 	// Commit creates a Commitment for the given Blob.
-	Commit(blob Blob) (Commitment, error)
+	Commit(blobs []Blob) ([]Commitment, error)
 
 	// Submit submits a Blob to Data Availability layer.
 	//
 	// This method is synchronous. Upon successful submission to Data Availability layer, it returns ID identifying blob
 	// in DA and Proof of inclusion.
-	Submit(blob Blob) (ID, Proof, error)
+	Submit(blobs []Blob) ([]ID, []Proof, error)
 
 	// Validate validates Commitment against Proof. This should be possible without retrieving Blob.
-	Validate(commit Commitment, proof Proof) (bool, error)
-}
-
-// BatchDA is a batched version of DA interface.
-type BatchDA interface {
-	Get(ids []ID) ([]Blob, error)
-	Commit(blobs []Blob) ([]Commitment, error)
-	Submit(blobs []Blob) ([]ID, []Proof, error)
-	Validate(commits []Commitment, proofs []Proof) ([]bool, error)
+	Validate(commits []ID, proofs []Proof) ([]bool, error)
 }
 
 // Blob is the data submitted/received from DA interface.
diff --git a/da_test.go b/da_test.go
index f24e1a5..ff0d3f6 100644
--- a/da_test.go
+++ b/da_test.go
@@ -18,21 +18,25 @@ func TestDummyDA(t *testing.T) {
 	})
 }
 
+// TODO(tzdybal): how to get rid of this?!
+type Blob = da.Blob
+type ID = da.ID
+
 func ExecuteDATest(t *testing.T, da da.DA) {
 	msg1 := []byte("message 1")
 	msg2 := []byte("message 2")
 
-	id1, proof1, err := da.Submit(msg1)
+	id1, proof1, err := da.Submit([]Blob{msg1})
 	assert.NoError(t, err)
 	assert.NotEmpty(t, id1)
 	assert.NotEmpty(t, proof1)
 
-	id2, proof2, err := da.Submit(msg2)
+	id2, proof2, err := da.Submit([]Blob{msg2})
 	assert.NoError(t, err)
 	assert.NotEmpty(t, id2)
 	assert.NotEmpty(t, proof2)
 
-	id3, proof3, err := da.Submit(msg1)
+	id3, proof3, err := da.Submit([]Blob{msg1})
 	assert.NoError(t, err)
 	assert.NotEmpty(t, id3)
 	assert.NotEmpty(t, proof3)
@@ -42,31 +46,40 @@ func ExecuteDATest(t *testing.T, da da.DA) {
 
 	ret, err := da.Get(id1)
 	assert.NoError(t, err)
-	assert.Equal(t, msg1, ret)
+	assert.Equal(t, []Blob{msg1}, ret)
 
-	commitment1, err := da.Commit(msg1)
+	commitment1, err := da.Commit([]Blob{msg1})
 	assert.NoError(t, err)
 	assert.NotEmpty(t, commitment1)
 
-	commitment2, err := da.Commit(msg2)
+	commitment2, err := da.Commit([]Blob{msg2})
 	assert.NoError(t, err)
 	assert.NotEmpty(t, commitment2)
 
-	ok, err := da.Validate(commitment1, proof1)
+	oks, err := da.Validate(commitment1, proof1)
 	assert.NoError(t, err)
-	assert.True(t, ok)
+	assert.NotEmpty(t, oks)
+	for _, ok := range oks {
+		assert.True(t, ok)
+	}
 
-	ok, err = da.Validate(commitment1, proof2)
+	oks, err = da.Validate(commitment1, proof2)
 	assert.NoError(t, err)
-	assert.False(t, ok)
+	assert.NotEmpty(t, oks)
+	for _, ok := range oks {
+		assert.False(t, ok)
+	}
 
-	ok, err = da.Validate(commitment2, proof1)
+	oks, err = da.Validate(commitment2, proof1)
 	assert.NoError(t, err)
-	assert.False(t, ok)
+	assert.NotEmpty(t, oks)
+	for _, ok := range oks {
+		assert.False(t, ok)
+	}
 }
 
 func CheckErrors(t *testing.T, da da.DA) {
-	blob, err := da.Get([]byte("invalid"))
+	blob, err := da.Get([]ID{[]byte("invalid")})
 	assert.Error(t, err)
 	assert.Empty(t, blob)
 }
diff --git a/dummy_test.go b/dummy_test.go
index 4e4bb64..3a6bb2d 100644
--- a/dummy_test.go
+++ b/dummy_test.go
@@ -30,28 +30,51 @@ func NewDummyDA() *DummyDA {
 	return da
 }
 
-func (d *DummyDA) Get(id da.ID) (da.Blob, error) {
-	blob, ok := d.data[string(id)]
-	if !ok {
-		return nil, errors.New("no blob for given ID")
+var _ da.DA = &DummyDA{}
+
+func (d *DummyDA) Get(ids []da.ID) ([]da.Blob, error) {
+	blobs := make([]da.Blob, len(ids))
+	for i, id := range ids {
+		blob, ok := d.data[string(id)]
+		if !ok {
+			return nil, errors.New("no blob for given ID")
+		}
+		blobs[i] = blob
 	}
-	return blob, nil
+	return blobs, nil
 }
 
-func (d *DummyDA) Commit(blob da.Blob) (da.Commitment, error) {
-	return d.getHash(blob), nil
+func (d *DummyDA) Commit(blobs []da.Blob) ([]da.Commitment, error) {
+	commits := make([]da.Commitment, len(blobs))
+	for i, blob := range blobs {
+		commits[i] = d.getHash(blob)
+	}
+	return commits, nil
 }
 
-func (d *DummyDA) Submit(blob da.Blob) (da.ID, da.Proof, error) {
-	id := d.nextID()
-	proof := d.getProof(id, blob)
+func (d *DummyDA) Submit(blobs []da.Blob) ([]da.ID, []da.Proof, error) {
+	ids := make([]da.ID, len(blobs))
+	proofs := make([]da.Proof, len(blobs))
+	for i, blob := range blobs {
+		id := d.nextID()
+		ids[i] = id
+		proofs[i] = d.getProof(id, blob)
+
+		d.data[string(id)] = blob
+	}
 
-	d.data[string(id)] = blob
-	return id, proof, nil
+	return ids, proofs, nil
 }
 
-func (d *DummyDA) Validate(commit da.Commitment, proof da.Proof) (bool, error) {
-	return ed25519.Verify(d.pubKey, commit, proof), nil
+func (d *DummyDA) Validate(ids []da.ID, proofs []da.Proof) ([]bool, error) {
+	if len(ids) != len(proofs) {
+		return nil, errors.New("number of IDs doesn't equal to number of proofs")
+	}
+	results := make([]bool, len(ids))
+	for i := 0; i < len(ids); i++ {
+		results[i] = ed25519.Verify(d.pubKey, ids[i], proofs[i])
+	}
+	return results, nil
 }
 
 func (d *DummyDA) nextID() []byte {