diff --git a/.beads/interactions.jsonl b/.beads/interactions.jsonl
index 8b552a6281190cffe7a7519bd5ec5b0b6c445f03..e1bc68c14da3f75966ab7f55df79adb37c360dbf 100644
--- a/.beads/interactions.jsonl
+++ b/.beads/interactions.jsonl
@@ -28,3 +28,5 @@ {"id":"int-e3eda42e","kind":"field_change","created_at":"2026-05-23T11:17:06.762081Z","actor":"Eugene Blikh","issue_id":"tarantool-protobuf-awv","extra":{"field":"status","new_value":"closed","old_value":"in_progress","reason":"Closed"}}
 {"id":"int-a512d09e","kind":"field_change","created_at":"2026-05-23T13:17:50.84577Z","actor":"Eugene Blikh","issue_id":"tarantool-protobuf-w3u","extra":{"field":"status","new_value":"closed","old_value":"in_progress","reason":"Closed"}}
 {"id":"int-1b6998d4","kind":"field_change","created_at":"2026-05-23T17:07:06.194133Z","actor":"Eugene Blikh","issue_id":"tarantool-protobuf-asz","extra":{"field":"status","new_value":"closed","old_value":"in_progress","reason":"ra6 3h: maps (entry-as-pseudo-message) — encode walks the user map with lua_next (CLAUDE.md JIT exception), builds each entry payload in a stack-backed sub-buffer with synthetic tag(1,key) + tag(2,value), proto3-elides defaults independently for key and value, and emits outer tag + len + payload into the parent buffer. Map<,message> resolves the value sub-plan once and recurses through encode_body. Decode reads the entry payload bounded, dispatches inner id=1/id=2 (skipping anything else per spec), and lua_rawsets into a lazy-created result map table; missing key or value falls back to the proto3 zero. Reuses the existing list_stack_idx[] slot for the lazy map cache (a field is either repeated or map, never both). 12 new tests cover round-trip for ages_by_nickname (string→int32), nickname_by_age (int32→string), and addresses_by_label (string→message), plus default-elision, multi-key correctness, empty maps, and unknown-inner-id tolerance. Full suite 964/964 with PB_ENABLE_C=1."}}
 {"id":"int-bc164b8a","kind":"field_change","created_at":"2026-05-23T18:04:37.771425Z","actor":"Eugene Blikh","issue_id":"tarantool-protobuf-wyp","extra":{"field":"status","new_value":"closed","old_value":"in_progress","reason":"Closed"}}
+{"id":"int-b39fa74a","kind":"field_change","created_at":"2026-05-23T18:22:01.107078Z","actor":"Eugene Blikh","issue_id":"tarantool-protobuf-rmf","extra":{"field":"status","new_value":"closed","old_value":"in_progress","reason":"Closed"}}
+{"id":"int-8dbcb031","kind":"field_change","created_at":"2026-05-23T18:38:56.610443Z","actor":"Eugene Blikh","issue_id":"tarantool-protobuf-m7u","extra":{"field":"status","new_value":"closed","old_value":"in_progress","reason":"Closed"}}
diff --git a/.beads/issues.jsonl b/.beads/issues.jsonl
index 74b36836c2c67aeedc8673b286b0d8e4e4a6c87a..0bb20177e4c280b290531c006a4f9f308d203a89 100644
--- a/.beads/issues.jsonl
+++ b/.beads/issues.jsonl
@@ -16,7 +16,7 @@ {"_type":"issue","id":"tarantool-protobuf-h8v","title":"Encoder: codegen-time inline FFI writes (mode=full)","description":"Replace per-field wire.encode_* calls + ../table.concat chain with directly-emitted FFI byte writes at every field site in mode=full. Today every encode_len(s) is 'encode_varint(#s) .. s' — two allocations and a concat per string. Sidesteps the per-byte b:alloc(1) cliff that sank the earlier ibuf attempt (memory: tarantool_ibuf_perf). Expected: 1.5-2x encode throughput; alloc/op drops from ~130 KB at 100 KB Person to near zero. Biggest single perf move. Bench reference: bench/starwing_bench.lua + bench/COMPARISON.md show starwing C encoder at 2.3-3x ours across all sizes.","status":"closed","priority":1,"issue_type":"task","assignee":"Eugene Blikh","owner":"bigbes@gmail.com","created_at":"2026-05-17T15:47:04Z","created_by":"Eugene Blikh","updated_at":"2026-05-18T18:31:54Z","started_at":"2026-05-18T18:25:39Z","closed_at":"2026-05-18T18:31:54Z","close_reason":"Inlined 1-byte varint length prefix at every LEN emit site; +25-48% encode at 1KB+ Person. Full FFI-buffer rewrite deferred — this slice captured the dominant profile target without that level of disruption. See bench/PERF_LOG.md entry for details.","labels":["codegen","encoder","perf"],"dependency_count":0,"dependent_count":2,"comment_count":0}
 {"_type":"issue","id":"tarantool-protobuf-e4t","title":"LSP: plugin emits @class type stubs for generated messages","description":"Phase 3 of the LSP / LLM affordance work. Follows phase 1 (commit 8721548 — runtime annotations) and phase 2 (bd-74c — annotate codec/grpc/json/wkt).\n\nHighest-payoff phase for LLM grounding. Modify the protoc plugin (cmd/protoc-gen-tarantool/internal/gen) so each generated _pb.lua module emits ---@class blocks describing every message, plus typed @param/@return on the _encode/_decode/_descriptor surface. After this lands, anyone (human or LLM) who require('full.hello.hello_pb') gets full type info on Person, Address, etc., without reading the .proto.\n\nEmit shape (decision: inline at top of generated file; one file per .proto already includes all messages from that file):\n\n  ---@class hello.Person\n  ---@field name?           string\n  ---@field user_id?        ffi.cdata*           # uint64\n  ---@field age?            integer              # int32\n  ---@field weight_kg?      number               # double\n  ---@field emails?         string[]\n  ---@field address?        hello.Address\n  ---@field lucky_numbers?  integer[]\n  ---@field favorite_color? hello.Color          # enum alias\n  ---@field tags?           table\u003cstring,string\u003e # map\u003cstring,string\u003e\n  ---@field unknown_fields? string\n\n  ---@param tbl hello.Person\n  ---@return string\n  function M.Person_encode(tbl) ... end\n\n  ---@param bytes string\n  ---@return hello.Person\n  function M.Person_decode(bytes) ... end\n\nField-kind -\u003e Lua-type mapping:\n- scalar int32/uint32/sint32/fixed32/sfixed32/bool → integer/boolean\n- scalar int64/uint64/sint64/fixed64/sfixed64 → ffi.cdata* (LuaJIT cdata, per project convention)\n- scalar float/double → number\n- scalar string/bytes → string\n- enum → alias of integer (emit ---@alias hello.Color integer)\n- message → another @class reference\n- repeated T → T[]\n- map\u003cK,V\u003e → table\u003cK_lua, V_lua\u003e\n- oneof — all members are optional, generator should NOT emit a discriminator field; user calls view:which() / inspects which value is non-nil\n\nAll fields are optional (? suffix) since proto3 default-elision means absence-on-wire is indistinguishable from default value. Required fields in proto2 omit the ?.\n\nBoth mode=full and mode=runtime emit the same _encode/_decode wrapper signatures, so the stubs apply uniformly.\n\nVerify by:\n1. Regenerating examples/expected/ via just gen\n2. Confirming the generated _pb.lua files load and pass tests (no behavior change)\n3. Opening examples/expected/full/hello/hello_pb.lua in an LSP-aware editor and checking that hover on hello.Person, M.Person_encode shows the @class + typed signature\n4. Sanity: require a generated module from spike code and confirm autocomplete on the result-table field names","acceptance_criteria":"Plugin emits ---@class blocks + typed _encode/_decode signatures into every generated _pb.lua; just gen + just test pass; LSP hover on require('full.hello.hello_pb').Person_encode shows ---@param tbl hello.Person ---@return string; ---@class hello.Person is reachable via hover on a decoded value","status":"open","priority":2,"issue_type":"feature","owner":"bigbes@gmail.com","created_at":"2026-05-23T09:30:19Z","created_by":"Eugene Blikh","updated_at":"2026-05-23T09:30:19Z","labels":["codegen","lsp"],"dependencies":[{"issue_id":"tarantool-protobuf-e4t","depends_on_id":"tarantool-protobuf-74c","type":"blocks","created_at":"2026-05-23T12:30:18Z","created_by":"Eugene Blikh","metadata":"{}"}],"dependency_count":1,"dependent_count":0,"comment_count":0}
 {"_type":"issue","id":"tarantool-protobuf-74c","title":"LSP: annotate codec/grpc/json/wkt with EmmyLua types","description":"Phase 2 of the LSP / LLM affordance work (phase 1 landed in commit 8721548 — .luarc.json, runtime/pb/_types.lua, init.lua + lazy.lua annotations).\n\nAdd ---@param / ---@return annotations to the remaining public-surface modules so editor hover and LLM context show types beyond just init.lua and the lazy views:\n\n- runtime/pb/codec.lua — encode(desc, t) / decode(desc, b); compile_writers / compile_readers (called from pb.finalize_message)\n- runtime/pb/grpc.lua — loopback / multiplex transport factories; the service client (factory(transport) -\u003e client_methods) and server (impl -\u003e {service, methods}) shapes\n- runtime/pb/json.lua — pb.json.encode(desc, t, opts) / pb.json.decode(desc, s, opts); opts shape (preserve_proto_field_names, emit_unpopulated, ...)\n- runtime/pb/wkt.lua — register(full_name, desc), lookup, any_pack/any_unpack, NULL sentinel\n\nFoundational @class declarations (pb.Descriptor, pb.Field, pb.GrpcTransport, pb.Json, pb.Wkt, pb.Module) already live in runtime/pb/_types.lua — extend as needed for opts shapes / map\u003cK,V\u003e generics.\n\nPure metadata change — no runtime behavior. Verify by running just test (must stay at 748 passing) and by opening a generated _pb.lua in an LSP-aware editor and confirming hover on require('pb').encode / .grpc.loopback / .json.encode shows the right signatures.","acceptance_criteria":"just test still green (748+ tests); hover in lua-language-server-aware editor shows typed signatures for pb.encode, pb.decode, grpc.loopback, json.encode, json.decode, wkt.register","status":"open","priority":2,"issue_type":"task","owner":"bigbes@gmail.com","created_at":"2026-05-23T09:29:55Z","created_by":"Eugene Blikh","updated_at":"2026-05-23T09:29:55Z","labels":["docs","lsp"],"dependency_count":0,"dependent_count":1,"comment_count":0}
 {"_type":"issue","id":"tarantool-protobuf-rmf","title":"ra6 3k: WKT override-hook passthrough","description":"If a plan's descriptor has desc.encode and desc.decode set (the WKT pattern from runtime/pb/wkt.lua), the C runtime must call those Lua functions instead of walking fields. Plan compiler stores luaL_ref to those functions; encode/decode entry points check first. This is also the extension point for future per-message codegen C (c0i) — same hook. Depends on 3a only (just adds a check at entry to the encode/decode loop). Acceptance: hello.Event (uses Timestamp, Duration, Any, FieldMask, Wrappers, Struct) round-trips with PB_ENABLE_C=1 producing byte-equal output to mode=full; the WKT module is unmodified.","status":"closed","priority":2,"issue_type":"task","assignee":"Eugene Blikh","owner":"bigbes@gmail.com","created_at":"2026-05-18T20:21:13Z","created_by":"Eugene Blikh","updated_at":"2026-05-23T18:22:01Z","started_at":"2026-05-23T18:17:19Z","closed_at":"2026-05-23T18:22:01Z","close_reason":"Closed","dependencies":[{"issue_id":"tarantool-protobuf-rmf","depends_on_id":"tarantool-protobuf-mq7","type":"blocks","created_at":"2026-05-18T23:21:55Z","created_by":"Eugene Blikh","metadata":"{}"}],"dependency_count":1,"dependent_count":1,"comment_count":0}
-{"_type":"issue","id":"tarantool-protobuf-m7u","title":"ra6 3i: proto2 — required, defaults, groups, extensions","description":"Proto2 semantic differences from proto3 that the C runtime must honor: (1) Required fields: decode-time enforcement when explicitly opted in (or default to skipping per existing pure-Lua behavior — match exactly); encode-time enforcement same. (2) Field defaults: present in the plan; emit them when missing on encode and substitute on decode where proto2 semantics require. (3) Groups (SGROUP/EGROUP wire format): encode/decode the framed group syntax. (4) Extensions: walk extension ranges, use plan-cached extension descriptor pointers, store in result._extensions. (5) Closed enum semantics for proto2. Depends on 3b + 3c + 3d + 3e + 3g + 3j (it's the join point — proto2 touches scalars, sub-messages, repeated, oneofs, unknown-fields). Acceptance: proto2_basic.BenchPayload and test_messages_proto2 round-trip byte-equal to mode=full at all bench sizes; conformance proto2 suite passes under PB_ENABLE_C=1.","status":"open","priority":2,"issue_type":"task","owner":"bigbes@gmail.com","created_at":"2026-05-18T20:21:03Z","created_by":"Eugene Blikh","updated_at":"2026-05-18T20:21:03Z","dependencies":[{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-hwe","type":"blocks","created_at":"2026-05-18T23:22:21Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-jc9","type":"blocks","created_at":"2026-05-18T23:22:22Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-mz6","type":"blocks","created_at":"2026-05-18T23:22:20Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-w3u","type":"blocks","created_at":"2026-05-18T23:22:22Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-wyp","type":"blocks","created_at":"2026-05-18T23:22:23Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-y1n","type":"blocks","created_at":"2026-05-18T23:22:20Z","created_by":"Eugene Blikh","metadata":"{}"}],"dependency_count":6,"dependent_count":1,"comment_count":0}
+{"_type":"issue","id":"tarantool-protobuf-m7u","title":"ra6 3i: proto2 — required, defaults, groups, extensions","description":"Proto2 semantic differences from proto3 that the C runtime must honor: (1) Required fields: decode-time enforcement when explicitly opted in (or default to skipping per existing pure-Lua behavior — match exactly); encode-time enforcement same. (2) Field defaults: present in the plan; emit them when missing on encode and substitute on decode where proto2 semantics require. (3) Groups (SGROUP/EGROUP wire format): encode/decode the framed group syntax. (4) Extensions: walk extension ranges, use plan-cached extension descriptor pointers, store in result._extensions. (5) Closed enum semantics for proto2. Depends on 3b + 3c + 3d + 3e + 3g + 3j (it's the join point — proto2 touches scalars, sub-messages, repeated, oneofs, unknown-fields). Acceptance: proto2_basic.BenchPayload and test_messages_proto2 round-trip byte-equal to mode=full at all bench sizes; conformance proto2 suite passes under PB_ENABLE_C=1.","status":"closed","priority":2,"issue_type":"task","assignee":"Eugene Blikh","owner":"bigbes@gmail.com","created_at":"2026-05-18T20:21:03Z","created_by":"Eugene Blikh","updated_at":"2026-05-23T18:38:57Z","started_at":"2026-05-23T18:26:23Z","closed_at":"2026-05-23T18:38:57Z","close_reason":"Closed","dependencies":[{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-hwe","type":"blocks","created_at":"2026-05-18T23:22:21Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-jc9","type":"blocks","created_at":"2026-05-18T23:22:22Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-mz6","type":"blocks","created_at":"2026-05-18T23:22:20Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-w3u","type":"blocks","created_at":"2026-05-18T23:22:22Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-wyp","type":"blocks","created_at":"2026-05-18T23:22:23Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-m7u","depends_on_id":"tarantool-protobuf-y1n","type":"blocks","created_at":"2026-05-18T23:22:20Z","created_by":"Eugene Blikh","metadata":"{}"}],"dependency_count":6,"dependent_count":1,"comment_count":0}
 {"_type":"issue","id":"tarantool-protobuf-asz","title":"ra6 3h: maps (entry-as-pseudo-message)","description":"map\u003cK,V\u003e fields are wire-encoded as repeated messages with synthetic Entry { key=1; value=2 } shape. Compile a map plan: outer field is K_REPEATED_MESSAGE with a synthesized Entry sub-plan. Encode: walk the Lua map via pairs(), emit each entry (this is the documented JIT exception — map fields are allowed pairs() in the hot path per CLAUDE.md). Decode: each entry yields a key + value, lua_settable into the result map. Depends on 3d (uses sub-message machinery). Acceptance: Person.ages_by_nickname / nickname_by_age / addresses_by_label round-trip; multi-key map fixtures behave correctly even though encode byte order differs (the existing map_test pattern).","status":"closed","priority":2,"issue_type":"task","assignee":"Eugene Blikh","owner":"bigbes@gmail.com","created_at":"2026-05-18T20:20:57Z","created_by":"Eugene Blikh","updated_at":"2026-05-23T17:07:06Z","started_at":"2026-05-23T16:45:29Z","closed_at":"2026-05-23T17:07:06Z","close_reason":"ra6 3h: maps (entry-as-pseudo-message) — encode walks the user map with lua_next (CLAUDE.md JIT exception), builds each entry payload in a stack-backed sub-buffer with synthetic tag(1,key) + tag(2,value), proto3-elides defaults independently for key and value, and emits outer tag + len + payload into the parent buffer. Map\u003c,message\u003e resolves the value sub-plan once and recurses through encode_body. Decode reads the entry payload bounded, dispatches inner id=1/id=2 (skipping anything else per spec), and lua_rawsets into a lazy-created result map table; missing key or value falls back to the proto3 zero. Reuses the existing list_stack_idx[] slot for the lazy map cache (a field is either repeated or map, never both). 12 new tests cover round-trip for ages_by_nickname (string→int32), nickname_by_age (int32→string), and addresses_by_label (string→message), plus default-elision, multi-key correctness, empty maps, and unknown-inner-id tolerance. Full suite 964/964 with PB_ENABLE_C=1.","dependencies":[{"issue_id":"tarantool-protobuf-asz","depends_on_id":"tarantool-protobuf-hwe","type":"blocks","created_at":"2026-05-18T23:22:19Z","created_by":"Eugene Blikh","metadata":"{}"}],"dependency_count":1,"dependent_count":1,"comment_count":0}
 {"_type":"issue","id":"tarantool-protobuf-wyp","title":"ra6 3j: unknown-fields capture","description":"A C-runtime decoder that meets fields not in the plan must capture their raw bytes into result._unknown_fields, and a subsequent C encode must re-emit them verbatim — same contract as test/unknown_test.lua against the pure-Lua paths. Bytes go in as a Lua string keyed by field number (mirror the existing convention). Depends on 3b + 3c (need the basic decode loop to know where to splice the unknown bytes). Acceptance: test/unknown_test.lua passes under PB_ENABLE_C=1; an evolved schema decoding bytes written by an old schema preserves the unknown fields through a C-side re-encode.","status":"closed","priority":2,"issue_type":"task","assignee":"Eugene Blikh","owner":"bigbes@gmail.com","created_at":"2026-05-18T20:20:40Z","created_by":"Eugene Blikh","updated_at":"2026-05-23T18:04:38Z","started_at":"2026-05-23T17:54:53Z","closed_at":"2026-05-23T18:04:38Z","close_reason":"Closed","dependencies":[{"issue_id":"tarantool-protobuf-wyp","depends_on_id":"tarantool-protobuf-mz6","type":"blocks","created_at":"2026-05-18T23:22:10Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-wyp","depends_on_id":"tarantool-protobuf-y1n","type":"blocks","created_at":"2026-05-18T23:22:09Z","created_by":"Eugene Blikh","metadata":"{}"}],"dependency_count":2,"dependent_count":2,"comment_count":0}
 {"_type":"issue","id":"tarantool-protobuf-w3u","title":"ra6 3g: oneofs","description":"Oneof groups: on encode, only the field with the current 'which' set is written; on decode, last-write-wins per the oneof group. Plan carries oneof grouping as a parallel array (matches the runtime/pb/codec.lua desc.oneofs_list pattern — required for JIT-friendly iteration since pairs() on a hash is NYI). Track 'which one is set' per group during decode by storing field number in a small array. Depends on 3b + 3c. Acceptance: hello.Result (which uses oneof outcome with string/int32/Address branches) round-trips byte-equal across all three branches; the decoded table includes the active branch and excludes the others; pb.lazy view's :which() returns the correct branch name.","status":"closed","priority":2,"issue_type":"task","assignee":"Eugene Blikh","owner":"bigbes@gmail.com","created_at":"2026-05-18T20:20:36Z","created_by":"Eugene Blikh","updated_at":"2026-05-23T13:17:51Z","started_at":"2026-05-23T13:15:43Z","closed_at":"2026-05-23T13:17:51Z","close_reason":"Closed","dependencies":[{"issue_id":"tarantool-protobuf-w3u","depends_on_id":"tarantool-protobuf-mz6","type":"blocks","created_at":"2026-05-18T23:22:08Z","created_by":"Eugene Blikh","metadata":"{}"},{"issue_id":"tarantool-protobuf-w3u","depends_on_id":"tarantool-protobuf-y1n","type":"blocks","created_at":"2026-05-18T23:22:08Z","created_by":"Eugene Blikh","metadata":"{}"}],"dependency_count":2,"dependent_count":2,"comment_count":0}