diff --git a/.planning/debug/buf-v1-graph-format.md b/.planning/debug/buf-v1-graph-format.md
new file mode 100644
index 0000000..a67225d
--- /dev/null
+++ b/.planning/debug/buf-v1-graph-format.md
@@ -0,0 +1,69 @@
+---
+status: resolved
+trigger: "buf 1.69.0 crashes with nil pointer dereference in graph_provider.go:140 when running `buf dep update` against the proxy."
+created: 2026-06-01
+updated: 2026-06-01
+---
+
+# Debug Session: buf-v1-graph-format
+
+## Symptoms
+
+- **Expected behavior:** `buf dep update` succeeds when pointing at the local proxy
+- **Actual behavior phase 1:** panic with nil pointer dereference at `bufmoduleapi/graph_provider.go:140`
+- **Actual behavior phase 2:** after fixing phase 1, `invalid_argument: unmarshal message: string field contains invalid UTF-8`
+- **Actual behavior phase 3:** after fixing phase 2, `*** Digest verification failed ***`
+- **Final result:** `buf dep update` exits with code 0
+
+## Root Cause
+
+Buf 1.69.0 uses `DigestTypeB5` (b5) as the default digest type. This causes it to use the **v1 API** (not v1beta1) for all module operations. The proxy was built for the v1beta1 API and had three separate issues.
+
+### Issue 1: v1 GraphService request format
+
+Buf's v1 `GetGraphRequest` uses `repeated ResourceRef` directly in field 1, while v1beta1 wraps each in `GetGraphRequest_ResourceRef { ResourceRef, Registry }`. The proxy's `ServeGraph` handler used a single parser (`parseGetGraphResourceRefs`) that only understood the v1beta1 format, causing v1 requests to return an empty graph → `response.Msg.Graph == nil` → nil pointer dereference.
+
+### Issue 2: v1 GraphService response format
+
+The v1 `Graph.commits` expects `repeated Commit` directly (no wrapper), while v1beta1 wraps each in `Graph_Commit { Commit, Registry }`. The proxy returned the v1beta1 format on both paths, causing buf to mis-parse the response → `invalid UTF-8`.
+
+### Issue 3: B5 digest computation
+
+The v1 `DigestType` enum has no B4 (`DIGEST_TYPE_B5 = 1` is the only valid type). Buf uses B5 digests, which are computed differently from B4:
+- B4: `SHA3-Shake256(manifest_text)`
+- B5: `SHA3-Shake256("shake256:" + hex(SHA3-Shake256(manifest_text)))` (wraps B4 hash as a string)
+
+The proxy returned B4 digest values tagged as wire-type 1 (= B5 in v1), causing verification failure.
+
+## Fix
+
+### Changed files:
+
+- `internal/connect/commits.go` — Three fixes:
+  1. `ServeGraph`: detect v1 vs v1beta1 path, use appropriate request parser and response format
+  2. `ServeHTTP` (CommitService): apply `toB5Digest()` on v1 path
+  3. `ServeGraph`: apply `toB5Digest()` on v1 path
+  4. `ServeDownload`: apply `toB5Digest()` on v1 path
+  5. Added `toB5Digest()` helper function
+- `internal/connect/commits_helpers.go` — Added `parseGetGraphResourceRefsV1` for v1 request format
+- `internal/connect/api_test.go` — Updated tests to use correct request format for each path
+
+### How:
+
+**Request parsing:**
+- v1beta1 path → uses `parseGetGraphResourceRefs` (existing, wrapped format)
+- v1 path → uses `parseGetGraphResourceRefsV1` (new, direct ResourceRef format)
+
+**Response format:**
+- v1beta1 path → wraps each commit in `Graph_Commit { Commit, Registry }`
+- v1 path → places `Commit` directly into `Graph.commits`
+
+**Digest computation (`toB5Digest`):**
+- Computes `SHA3-Shake256("shake256:" + hex(b4_hash))` to match buf's B5 algorithm
+- Applied to all three v1 handler paths (CommitService, GraphService, DownloadService)
+
+## Verification
+
+- All existing tests pass
+- `buf dep update` in `/Users/nil/DiskD/W/yadro/cyp-hardware-manager/api/proto` exits with code 0
+- Generated buf.lock contains all 4 deps with correct B5 digests
diff --git a/internal/connect/api_test.go b/internal/connect/api_test.go
index 2f3b6e6..1bd21d1 100644
--- a/internal/connect/api_test.go
+++ b/internal/connect/api_test.go
@@ -84,6 +84,28 @@ func buildGetGraphRequest(owner, module string) []byte {
 	return req
 }
 
+// buildV1GetGraphRequest builds a v1-format GetGraph request with ResourceRef directly.
+// v1 GetGraphRequest: field 1 = repeated ResourceRef { name = 2; Name { owner=1; module=2 } }
+// (no GetGraphRequest_ResourceRef wrapper)
+func buildV1GetGraphRequest(owner, module string) []byte {
+	var name []byte
+	name = protowire.AppendTag(name, 1, protowire.BytesType)
+	name = protowire.AppendString(name, owner)
+	name = protowire.AppendTag(name, 2, protowire.BytesType)
+	name = protowire.AppendString(name, module)
+
+	var resRef []byte
+	resRef = protowire.AppendTag(resRef, 2, protowire.BytesType)
+	resRef = append(resRef, protowire.AppendVarint(nil, uint64(len(name)))...)
+	resRef = append(resRef, name...)
+
+	var req []byte
+	req = protowire.AppendTag(req, 1, protowire.BytesType)
+	req = append(req, protowire.AppendVarint(nil, uint64(len(resRef)))...)
+	req = append(req, resRef...)
+	return req
+}
+
 // buildDownloadRequest builds a protobuf-encoded Download request using a commit ID.
 func buildDownloadRequest(commitID string) []byte {
 	// ResourceRef: id=1
@@ -166,7 +188,7 @@ func TestV1RoutesNotReachingRootHandler(t *testing.T) {
 		body []byte
 	}{
 		{"CommitService v1", "/buf.registry.module.v1.CommitService/GetCommits", buildGetCommitsRequest("owner", "repo")},
-		{"GraphService v1", "/buf.registry.module.v1.GraphService/GetGraph", buildGetGraphRequest("owner", "repo")},
+		{"GraphService v1", "/buf.registry.module.v1.GraphService/GetGraph", buildV1GetGraphRequest("owner", "repo")},
 	}
 
 	for _, tc := range v1Paths {
@@ -261,13 +283,16 @@ func TestGraphServiceV1ReturnsProtobuf(t *testing.T) {
 	io.ReadAll(commitResp.Body)
 	commitResp.Body.Close()
 
-	for _, path := range []string{
-		"/buf.registry.module.v1.GraphService/GetGraph",
-		"/buf.registry.module.v1beta1.GraphService/GetGraph",
-	} {
-		t.Run(path, func(t *testing.T) {
-			body := buildGetGraphRequest("owner", "repo")
-			resp, err := http.Post(server.URL+path, "application/proto", bytes.NewReader(body))
+	testPaths := []struct {
+			path string
+			body []byte
+		}{
+			{"/buf.registry.module.v1.GraphService/GetGraph", buildV1GetGraphRequest("owner", "repo")},
+			{"/buf.registry.module.v1beta1.GraphService/GetGraph", buildGetGraphRequest("owner", "repo")},
+		}
+		for _, tc := range testPaths {
+			t.Run(tc.path, func(t *testing.T) {
+				resp, err := http.Post(server.URL+tc.path, "application/proto", bytes.NewReader(tc.body))
 			if err != nil {
 				t.Fatalf("request failed: %v", err)
 			}
diff --git a/internal/connect/commits.go b/internal/connect/commits.go
index 647b17c..76a268a 100644
--- a/internal/connect/commits.go
+++ b/internal/connect/commits.go
@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"encoding/hex"
+	"strings"
 	"sync"
 
 	"github.com/easyp-tech/server/internal/providers/content"
@@ -60,11 +62,19 @@ func (h *commitServiceHandler) ServeHTTP(w http.ResponseWriter, r *http.Request)
 			return
 		}
 		cid := deterministicID(meta.Commit)
+		isV1 := !strings.Contains(r.URL.Path, "v1beta1")
 		digest, err := h.computeB4Digest(r, ref, meta.Commit)
 		if err != nil {
 			http.Error(w, fmt.Sprintf("computing digest for %s/%s: %v", ref.owner, ref.module, err), http.StatusInternalServerError)
 			return
 		}
+		if isV1 {
+			digest, err = toB5Digest(digest)
+			if err != nil {
+				http.Error(w, fmt.Sprintf("wrapping digest for %s/%s: %v", ref.owner, ref.module, err), http.StatusInternalServerError)
+				return
+			}
+		}
 		commits = append(commits, commitInfo{
 			ownerID:  deterministicID(ref.owner),
 			moduleID: deterministicID(ref.owner + "/" + ref.module),
@@ -124,9 +134,15 @@ func (h *commitServiceHandler) ServeGraph(w http.ResponseWriter, r *http.Request
 		return
 	}
 
-	// Parse GetGraphRequest: field 1 (resource_refs) repeated GetGraphRequest_ResourceRef
-	// Each GetGraphRequest_ResourceRef has: field 1 (ResourceRef) + field 2 (Registry string)
-	refs := parseGetGraphResourceRefs(body)
+	// Parse GetGraphRequest - handle both v1 and v1beta1 formats:
+	// v1beta1: field 1 = repeated GetGraphRequest_ResourceRef { ResourceRef, Registry }
+	isV1 := !strings.Contains(r.URL.Path, "v1beta1")
+	var refs []moduleRef
+	if isV1 {
+		refs = parseGetGraphResourceRefsV1(body)
+	} else {
+		refs = parseGetGraphResourceRefs(body)
+	}
 	if len(refs) == 0 {
 		// Return empty graph
 		w.Header().Set("Content-Type", "application/proto")
@@ -170,6 +186,13 @@ func (h *commitServiceHandler) ServeGraph(w http.ResponseWriter, r *http.Request
 			http.Error(w, fmt.Sprintf("computing digest for %s/%s: %v", ref.owner, ref.module, err), http.StatusInternalServerError)
 			return
 		}
+		if isV1 {
+			digest, err = toB5Digest(digest)
+			if err != nil {
+				http.Error(w, fmt.Sprintf("converting digest for %s/%s: %v", ref.owner, ref.module, err), http.StatusInternalServerError)
+				return
+			}
+		}
 		commits = append(commits, commitInfo{
 			ownerID:  deterministicID(ref.owner),
 			moduleID: deterministicID(ref.owner + "/" + ref.module),
@@ -180,25 +203,32 @@ func (h *commitServiceHandler) ServeGraph(w http.ResponseWriter, r *http.Request
 		})
 	}
 
-	// Build Graph response:
-	//   GetGraphResponse { field 1: Graph { field 1: [Graph_Commit...], field 2: [Graph_Edge...] } }
-	//   Graph_Commit { field 1 (Commit), field 2 (Registry) }
+	// Build Graph response.
+	// v1:       Graph.commits = repeated Commit (direct, no wrapper, no registry)
+	// v1beta1:  Graph.commits = repeated Graph_Commit { Commit, Registry }
+	// Both:     GetGraphResponse { field 1: Graph { field 1: commits, field 2: edges (empty) } }
 	var graphMsg []byte
 	for _, c := range commits {
 		commit := buildCommitRaw(c.commitID, c.ownerID, c.moduleID, c.digest)
 
-		// Build Graph_Commit wrapper: field 1 (Commit), field 2 (Registry)
-		var graphCommit []byte
-		graphCommit = protowire.AppendTag(graphCommit, 1, protowire.BytesType)
-		graphCommit = append(graphCommit, protowire.AppendVarint(nil, uint64(len(commit)))...)
-		graphCommit = append(graphCommit, commit...)
-		graphCommit = protowire.AppendTag(graphCommit, 2, protowire.BytesType)
-		graphCommit = protowire.AppendString(graphCommit, h.api.domain)
-
-		// Append to Graph.commits (field 1, repeated)
-		graphMsg = protowire.AppendTag(graphMsg, 1, protowire.BytesType)
-		graphMsg = append(graphMsg, protowire.AppendVarint(nil, uint64(len(graphCommit)))...)
-		graphMsg = append(graphMsg, graphCommit...)
+		if isV1 {
+			// v1: Commit goes directly into Graph.commits (field 1)
+			graphMsg = protowire.AppendTag(graphMsg, 1, protowire.BytesType)
+			graphMsg = append(graphMsg, protowire.AppendVarint(nil, uint64(len(commit)))...)
+			graphMsg = append(graphMsg, commit...)
+		} else {
+			// v1beta1: wrap in Graph_Commit { field 1 = Commit, field 2 = Registry }
+			var graphCommit []byte
+			graphCommit = protowire.AppendTag(graphCommit, 1, protowire.BytesType)
+			graphCommit = append(graphCommit, protowire.AppendVarint(nil, uint64(len(commit)))...)
+			graphCommit = append(graphCommit, commit...)
+			graphCommit = protowire.AppendTag(graphCommit, 2, protowire.BytesType)
+			graphCommit = protowire.AppendString(graphCommit, h.api.domain)
+
+			graphMsg = protowire.AppendTag(graphMsg, 1, protowire.BytesType)
+			graphMsg = append(graphMsg, protowire.AppendVarint(nil, uint64(len(graphCommit)))...)
+			graphMsg = append(graphMsg, graphCommit...)
+		}
 	}
 
 	// Wrap Graph in GetGraphResponse: field 1 (Graph)
@@ -263,6 +293,9 @@ func (h *commitServiceHandler) ServeDownload(w http.ResponseWriter, r *http.Requ
 		}
 		cid = deterministicID(meta.Commit)
 		digest, _ = h.computeB4DigestFromFiles(files)
+		if !strings.Contains(r.URL.Path, "v1beta1") {
+			digest, _ = toB5Digest(digest)
+		}
 	}
 
 	commit := buildCommitRaw(cid, cached.ownerID, cached.moduleID, digest)
@@ -296,6 +329,17 @@ func (h *commitServiceHandler) ServeDownload(w http.ResponseWriter, r *http.Requ
 	w.Header().Set("Content-Type", "application/proto")
 	_, _ = w.Write(respMsg)
 }
+func toB5Digest(b4Digest []byte) ([]byte, error) {
+	// B5 digest wraps B4 (shake256) value: SHA3-Shake256("shake256:" + hex(b4_hash))
+	// This matches buf's getB5DigestForBucketAndDepDigests with zero dependencies.
+	digestStr := "shake256:" + hex.EncodeToString(b4Digest)
+	hash, err := shake256.SHA3Shake256([]byte(digestStr))
+	if err != nil {
+		return nil, err
+	}
+	return hash[:], nil
+}
+
 
 func (h *commitServiceHandler) computeB4Digest(r *http.Request, ref moduleRef, commit string) ([]byte, error) {
 	files, err := h.api.repo.GetFiles(r.Context(), ref.owner, ref.module, commit)
diff --git a/internal/connect/commits_helpers.go b/internal/connect/commits_helpers.go
index 3afe8a4..82b14f7 100644
--- a/internal/connect/commits_helpers.go
+++ b/internal/connect/commits_helpers.go
@@ -127,6 +127,35 @@ func parseGetGraphResourceRefs(msg []byte) []moduleRef {
 	return refs
 }
 
+// parseGetGraphResourceRefsV1 parses v1 GetGraphRequest where field 1 contains ResourceRef directly.
+// v1 GetGraphRequest: field 1 = repeated ResourceRef { Name { owner, module, ref } }
+// (no GetGraphRequest_ResourceRef wrapper)
+func parseGetGraphResourceRefsV1(msg []byte) []moduleRef {
+	var refs []moduleRef
+	for len(msg) > 0 {
+		num, typ, n := protowire.ConsumeTag(msg)
+		if n < 0 {
+			break
+		}
+		msg = msg[n:]
+		if num == 1 && typ == protowire.BytesType {
+			v, mLen := protowire.ConsumeBytes(msg)
+			msg = msg[mLen:]
+			// v is ResourceRef directly (not wrapped in GetGraphRequest_ResourceRef)
+			if ref := parseResourceRef(v); ref != nil {
+				refs = append(refs, *ref)
+			}
+		} else {
+			n = protowire.ConsumeFieldValue(num, typ, msg)
+			if n < 0 {
+				break
+			}
+			msg = msg[n:]
+		}
+	}
+	return refs
+}
+
 func extractField1(msg []byte) []byte {
 	for len(msg) > 0 {
 		num, typ, n := protowire.ConsumeTag(msg)