diff --git a/codex/codex_test.go b/codex/codex_test.go
index ae973c2..d0cb91f 100644
--- a/codex/codex_test.go
+++ b/codex/codex_test.go
@@ -3,8 +3,7 @@ package codex
 import "testing"
 
 func TestCodexVersion(t *testing.T) {
-	start := false
-	node := newCodexNode(t, start)
+	node := newCodexNode(t, withNoStart())
 
 	version, err := node.Version()
 	if err != nil {
@@ -18,8 +17,7 @@ func TestCodexVersion(t *testing.T) {
 }
 
 func TestCodexRevision(t *testing.T) {
-	start := false
-	node := newCodexNode(t, start)
+	node := newCodexNode(t, withNoStart())
 
 	revision, err := node.Revision()
 	if err != nil {
@@ -33,8 +31,7 @@ func TestCodexRevision(t *testing.T) {
 }
 
 func TestCodexRepo(t *testing.T) {
-	start := true
-	node := newCodexNode(t, start)
+	node := newCodexNode(t)
 
 	repo, err := node.Repo()
 	if err != nil {
@@ -48,8 +45,7 @@ func TestCodexRepo(t *testing.T) {
 }
 
 func TestSpr(t *testing.T) {
-	start := true
-	node := newCodexNode(t, start)
+	node := newCodexNode(t)
 
 	spr, err := node.Spr()
 	if err != nil {
@@ -63,8 +59,7 @@ func TestSpr(t *testing.T) {
 }
 
 func TestPeerId(t *testing.T) {
-	start := true
-	node := newCodexNode(t, start)
+	node := newCodexNode(t)
 
 	peerId, err := node.PeerId()
 	if err != nil {
diff --git a/codex/debug_test.go b/codex/debug_test.go
index af9d5af..9355347 100644
--- a/codex/debug_test.go
+++ b/codex/debug_test.go
@@ -8,8 +8,7 @@ import (
 )
 
 func TestDebug(t *testing.T) {
-	start := true
-	codex := newCodexNode(t, start)
+	codex := newCodexNode(t)
 
 	info, err := codex.Debug()
 	if err != nil {
diff --git a/codex/download_test.go b/codex/download_test.go
index 0827da3..19c2855 100644
--- a/codex/download_test.go
+++ b/codex/download_test.go
@@ -1,28 +1,13 @@
 package codex
 
 import (
-	"bytes"
 	"os"
 	"strings"
 	"testing"
 )
 
-func uploadHelper(t *testing.T, codex *CodexNode) (string, int) {
-	t.Helper()
-
-	buf := bytes.NewBuffer([]byte("Hello World!"))
-	len := buf.Len()
-	cid, err := codex.UploadReader(UploadOptions{filepath: "hello.txt"}, buf)
-	if err != nil {
-		t.Fatalf("Error happened during upload: %v\n", err)
-	}
-
-	return cid, len
-}
-
 func TestDownloadStream(t *testing.T) {
-	start := true
-	codex := newCodexNode(t, start)
+	codex := newCodexNode(t)
 	cid, len := uploadHelper(t, codex)
 
 	f, err := os.Create("testdata/hello.downloaded.txt")
@@ -59,7 +44,7 @@ func TestDownloadStream(t *testing.T) {
 		t.Fatalf("UploadReader progress callback total bytes %d but expected %d", totalBytes, len)
 	}
 
-	data, err := os.ReadFile("testdata/hello.writer.txt")
+	data, err := os.ReadFile("testdata/hello.downloaded.writer.txt")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -70,8 +55,7 @@ func TestDownloadStream(t *testing.T) {
 }
 
 func TestDownloadStreamWithAutosize(t *testing.T) {
-	start := true
-	codex := newCodexNode(t, start)
+	codex := newCodexNode(t)
 	cid, len := uploadHelper(t, codex)
 
 	totalBytes := 0
@@ -101,9 +85,17 @@ func TestDownloadStreamWithAutosize(t *testing.T) {
 	}
 }
 
+func TestDownloadStreamWithNotExisting(t *testing.T) {
+	codex := newCodexNode(t, withBlockRetries(1))
+
+	opt := DownloadStreamOptions{}
+	if err := codex.DownloadStream("bafybeihdwdcefgh4dqkjv67uzcmw7ojee6xedzdetojuzjevtenxquvyku", opt); err == nil {
+		t.Fatal("Error expected when downloading non-existing cid")
+	}
+}
+
 func TestDownloadManual(t *testing.T) {
-	start := true
-	codex := newCodexNode(t, start)
+	codex := newCodexNode(t)
 	cid, _ := uploadHelper(t, codex)
 
 	if err := codex.DownloadInit(cid, DownloadInitOptions{}); err != nil {
@@ -126,3 +118,38 @@ func TestDownloadManual(t *testing.T) {
 		t.Fatalf("Error when cancelling the download %s", err)
 	}
 }
+
+func TestDownloadManifest(t *testing.T) {
+	codex := newCodexNode(t)
+	cid, _ := uploadHelper(t, codex)
+
+	manifest, err := codex.DownloadManifest(cid)
+	if err != nil {
+		t.Fatal("Error when downloading manifest:", err)
+	}
+
+	if manifest.Cid != cid {
+		t.Errorf("expected cid %q, got %q", cid, manifest.Cid)
+	}
+}
+
+func TestDownloadManifestWithNotExistingCid(t *testing.T) {
+	codex := newCodexNode(t, withBlockRetries(1))
+
+	manifest, err := codex.DownloadManifest("bafybeihdwdcefgh4dqkjv67uzcmw7ojee6xedzdetojuzjevtenxquvyku")
+	if err == nil {
+		t.Fatal("Error when downloading manifest:", err)
+	}
+
+	if manifest.Cid != "" {
+		t.Errorf("expected empty cid, got %q", manifest.Cid)
+	}
+}
+
+func TestDownloadInitWithNotExistingCid(t *testing.T) {
+	codex := newCodexNode(t, withBlockRetries(1))
+
+	if err := codex.DownloadInit("bafybeihdwdcefgh4dqkjv67uzcmw7ojee6xedzdetojuzjevtenxquvyku", DownloadInitOptions{}); err == nil {
+		t.Fatal("expected error when initializing download for non-existent cid")
+	}
+}
diff --git a/codex/testutil.go b/codex/testutil.go
index 69d4b73..3155ace 100644
--- a/codex/testutil.go
+++ b/codex/testutil.go
@@ -1,20 +1,44 @@
 package codex
 
 import (
+	"bytes"
 	"testing"
 )
 
-func newCodexNode(t *testing.T, start bool) *CodexNode {
+type codexNodeTestOption func(*codexNodeTestOptions)
+
+type codexNodeTestOptions struct {
+	noStart      bool
+	blockRetries int
+}
+
+func withNoStart() codexNodeTestOption {
+	return func(o *codexNodeTestOptions) { o.noStart = true }
+}
+
+func withBlockRetries(n int) codexNodeTestOption {
+	return func(o *codexNodeTestOptions) { o.blockRetries = n }
+}
+
+func newCodexNode(t *testing.T, opts ...codexNodeTestOption) *CodexNode {
+	o := codexNodeTestOptions{
+		blockRetries: 3000,
+	}
+	for _, opt := range opts {
+		opt(&o)
+	}
+
 	node, err := CodexNew(CodexConfig{
 		DataDir:        t.TempDir(),
 		LogFormat:      LogFormatNoColors,
 		MetricsEnabled: false,
+		BlockRetries:   o.blockRetries,
 	})
 	if err != nil {
 		t.Fatalf("Failed to create Codex node: %v", err)
 	}
 
-	if start {
+	if !o.noStart {
 		err = node.Start()
 		if err != nil {
 			t.Fatalf("Failed to start Codex node: %v", err)
@@ -22,7 +46,7 @@ func newCodexNode(t *testing.T, start bool) *CodexNode {
 	}
 
 	t.Cleanup(func() {
-		if start {
+		if !o.noStart {
 			if err := node.Stop(); err != nil {
 				t.Logf("cleanup codex: %v", err)
 			}
@@ -35,3 +59,16 @@ func newCodexNode(t *testing.T, start bool) *CodexNode {
 
 	return node
 }
+
+func uploadHelper(t *testing.T, codex *CodexNode) (string, int) {
+	t.Helper()
+
+	buf := bytes.NewBuffer([]byte("Hello World!"))
+	len := buf.Len()
+	cid, err := codex.UploadReader(UploadOptions{filepath: "hello.txt"}, buf)
+	if err != nil {
+		t.Fatalf("Error happened during upload: %v\n", err)
+	}
+
+	return cid, len
+}
diff --git a/codex/upload_test.go b/codex/upload_test.go
index 6e6657a..af04371 100644
--- a/codex/upload_test.go
+++ b/codex/upload_test.go
@@ -10,8 +10,7 @@ import (
 const expectedCID = "zDvZRwzmAkhzDRPH5EW242gJBNZ2T7aoH2v1fVH66FxXL4kSbvyM"
 
 func TestUploadReader(t *testing.T) {
-	start := true
-	codex := newCodexNode(t, start)
+	codex := newCodexNode(t)
 	totalBytes := 0
 	finalPercent := 0.0
 
@@ -44,8 +43,7 @@ func TestUploadReader(t *testing.T) {
 }
 
 func TestUploadFile(t *testing.T) {
-	start := true
-	codex := newCodexNode(t, start)
+	codex := newCodexNode(t)
 	totalBytes := 0
 	finalPercent := 0.0
 
@@ -82,8 +80,7 @@ func TestUploadFile(t *testing.T) {
 }
 
 func TestUploadFileNoProgress(t *testing.T) {
-	start := true
-	codex := newCodexNode(t, start)
+	codex := newCodexNode(t)
 
 	options := UploadOptions{filepath: "./testdata/doesnt_exist.txt"}
 
@@ -98,8 +95,7 @@ func TestUploadFileNoProgress(t *testing.T) {
 }
 
 func TestManualUpload(t *testing.T) {
-	start := true
-	codex := newCodexNode(t, start)
+	codex := newCodexNode(t)
 
 	sessionId, err := codex.UploadInit(&UploadOptions{filepath: "hello.txt"})
 	if err != nil {