diff --git a/.golangci.yml b/.golangci.yml
index b4ed47a..5023093 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -4,7 +4,7 @@ run:
   timeout: 5m
   tests: true
   build-tags:
-    - sqlite_cgo
+    - sqlite_fts5
 
 linters:
   default: none
diff --git a/Dockerfile b/Dockerfile
index e4f6121..e1eb2cf 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -28,7 +28,7 @@ RUN go mod download
 COPY cmd/ ./cmd/
 COPY internal/ ./internal/
 RUN CC=musl-gcc CGO_ENABLED=1 go build \
-        -tags "sqlite_omit_load_extension" \
+        -tags "sqlite_omit_load_extension sqlite_fts5" \
         -trimpath \
         -ldflags "-s -w -linkmode external -extldflags -static -X main.version=${VERSION} -X main.commit=${COMMIT} -X main.buildDate=${BUILD_DATE}" \
         -o /out/glchat ./cmd/glchat
diff --git a/Makefile b/Makefile
index cfa896f..33afe91 100644
--- a/Makefile
+++ b/Makefile
@@ -22,7 +22,10 @@ export GOPROXY ?= https://proxy.golang.org,direct
 export GOSUMDB ?= sum.golang.org
 export CGO_ENABLED ?= 1
 
-GOFLAGS_LOCAL    := -trimpath
+# sqlite_fts5 включает полнотекстовый поиск в mattn/go-sqlite3 (AGENT.md 7.15):
+# без тега поиск по сообщениям не работает, поэтому он обязателен для всех сборок.
+GO_TAGS          ?= sqlite_fts5
+GOFLAGS_LOCAL    := -trimpath -tags $(GO_TAGS)
 GO_LDFLAGS       := -s -w \
 	-X main.version=$(VERSION) \
 	-X main.commit=$(COMMIT) \
@@ -102,12 +105,12 @@ build: ## Собрать бинарник сервера в ./build/glchat
 
 .PHONY: test
 test: ## Тесты Go с race-детектором
-	go test -race -count=1 $(GO_PACKAGES)
+	go test -tags $(GO_TAGS) -race -count=1 $(GO_PACKAGES)
 
 .PHONY: test-cover
 test-cover: ## Тесты с отчётом покрытия (./build/coverage.out)
 	@mkdir -p $(BUILD_DIR)
-	go test -race -count=1 -coverprofile=$(BUILD_DIR)/coverage.out $(GO_PACKAGES)
+	go test -tags $(GO_TAGS) -race -count=1 -coverprofile=$(BUILD_DIR)/coverage.out $(GO_PACKAGES)
 	go tool cover -func=$(BUILD_DIR)/coverage.out | tail -1
 
 .PHONY: lint
diff --git a/internal/database/fts5_guard.go b/internal/database/fts5_guard.go
new file mode 100644
index 0000000..ed98bfc
--- /dev/null
+++ b/internal/database/fts5_guard.go
@@ -0,0 +1,10 @@
+//go:build !sqlite_fts5
+
+package database
+
+// Без тега sqlite_fts5 драйвер mattn/go-sqlite3 не умеет виртуальные таблицы
+// FTS5, и миграция поиска падает на старте. Паникуем сразу и с понятным
+// текстом: собрать инстанс без полнотекстового поиска нельзя (AGENT.md 7.15).
+func init() {
+	panic("glchat: сборка без тега sqlite_fts5 — добавьте -tags sqlite_fts5 (см. GO_TAGS в Makefile)")
+}
diff --git a/internal/database/migrations/00004_phase2_messages.sql b/internal/database/migrations/00004_phase2_messages.sql
new file mode 100644
index 0000000..d58c492
--- /dev/null
+++ b/internal/database/migrations/00004_phase2_messages.sql
@@ -0,0 +1,114 @@
+-- +goose Up
+-- Фаза 2: сообщения, реакции, закрепления, read states и полнотекстовый поиск
+-- (AGENT.md 6.1, 7.6, 7.15).
+
+CREATE TABLE messages (
+    id               INTEGER PRIMARY KEY,
+    channel_id       INTEGER NOT NULL REFERENCES channels (id) ON DELETE CASCADE,
+    author_id        INTEGER REFERENCES users (id) ON DELETE SET NULL,
+    content          TEXT    NOT NULL DEFAULT '',
+    reply_to_id      INTEGER REFERENCES messages (id) ON DELETE SET NULL,
+    type             TEXT    NOT NULL DEFAULT 'default',
+    -- Вложения хранятся списком метаданных: сами файлы лежат на диске (7.7).
+    attachments_json TEXT    NOT NULL DEFAULT '[]',
+    mentions_json    TEXT    NOT NULL DEFAULT '[]',
+    edited_at        TEXT,
+    pinned           INTEGER NOT NULL DEFAULT 0,
+    created_at       TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
+);
+CREATE INDEX messages_channel_idx ON messages (channel_id, id DESC);
+CREATE INDEX messages_author_idx ON messages (author_id, id DESC);
+CREATE INDEX messages_pinned_idx ON messages (channel_id, id) WHERE pinned = 1;
+
+CREATE TABLE message_reactions (
+    message_id INTEGER NOT NULL REFERENCES messages (id) ON DELETE CASCADE,
+    user_id    INTEGER NOT NULL REFERENCES users (id) ON DELETE CASCADE,
+    emoji      TEXT    NOT NULL,
+    created_at TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now')),
+    PRIMARY KEY (message_id, user_id, emoji)
+);
+CREATE INDEX message_reactions_emoji_idx ON message_reactions (message_id, emoji);
+
+-- Состояние прочтения на пользователя и комнату: синхронизируется между
+-- устройствами через Gateway (AGENT.md 7.16).
+CREATE TABLE channel_read_states (
+    user_id         INTEGER NOT NULL REFERENCES users (id) ON DELETE CASCADE,
+    channel_id      INTEGER NOT NULL REFERENCES channels (id) ON DELETE CASCADE,
+    last_message_id INTEGER NOT NULL DEFAULT 0,
+    mention_count   INTEGER NOT NULL DEFAULT 0,
+    updated_at      TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now')),
+    PRIMARY KEY (user_id, channel_id)
+);
+CREATE INDEX channel_read_states_channel_idx ON channel_read_states (channel_id);
+
+-- Вложения: файл регистрируется отдельно от сообщения, чтобы работали
+-- предпросмотры и очистка сирот (AGENT.md 7.7).
+CREATE TABLE files (
+    id            INTEGER PRIMARY KEY,
+    uploader_id   INTEGER REFERENCES users (id) ON DELETE SET NULL,
+    guild_id      INTEGER REFERENCES guilds (id) ON DELETE CASCADE,
+    channel_id    INTEGER REFERENCES channels (id) ON DELETE CASCADE,
+    message_id    INTEGER REFERENCES messages (id) ON DELETE CASCADE,
+    filename      TEXT    NOT NULL,
+    content_type  TEXT    NOT NULL DEFAULT 'application/octet-stream',
+    size_bytes    INTEGER NOT NULL DEFAULT 0,
+    width         INTEGER NOT NULL DEFAULT 0,
+    height        INTEGER NOT NULL DEFAULT 0,
+    storage_path  TEXT    NOT NULL DEFAULT '',
+    sha256        TEXT    NOT NULL DEFAULT '',
+    created_at    TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
+);
+CREATE INDEX files_message_idx ON files (message_id);
+
+-- Полнотекстовый поиск по сообщениям (AGENT.md 7.15): индексируем содержимое,
+-- права проверяются при запросе.
+CREATE VIRTUAL TABLE messages_fts USING fts5 (
+    content,
+    content = 'messages',
+    content_rowid = 'id',
+    tokenize = 'unicode61 remove_diacritics 2'
+);
+
+-- Триггеры содержат `;` внутри тела: goose требует явных границ оператора.
+-- +goose StatementBegin
+CREATE TRIGGER messages_fts_insert AFTER INSERT ON messages BEGIN
+    INSERT INTO messages_fts (rowid, content) VALUES (new.id, new.content);
+END;
+-- +goose StatementEnd
+-- +goose StatementBegin
+CREATE TRIGGER messages_fts_delete AFTER DELETE ON messages BEGIN
+    INSERT INTO messages_fts (messages_fts, rowid, content) VALUES ('delete', old.id, old.content);
+END;
+-- +goose StatementEnd
+-- +goose StatementBegin
+CREATE TRIGGER messages_fts_update AFTER UPDATE OF content ON messages BEGIN
+    INSERT INTO messages_fts (messages_fts, rowid, content) VALUES ('delete', old.id, old.content);
+    INSERT INTO messages_fts (rowid, content) VALUES (new.id, new.content);
+END;
+-- +goose StatementEnd
+
+-- Приглашения (AGENT.md 7.9): код, лимит использований и срок жизни.
+CREATE TABLE invites (
+    code        TEXT    PRIMARY KEY,
+    guild_id    INTEGER NOT NULL REFERENCES guilds (id) ON DELETE CASCADE,
+    channel_id  INTEGER REFERENCES channels (id) ON DELETE SET NULL,
+    creator_id  INTEGER REFERENCES users (id) ON DELETE SET NULL,
+    max_uses    INTEGER NOT NULL DEFAULT 0,
+    uses        INTEGER NOT NULL DEFAULT 0,
+    max_age_sec INTEGER NOT NULL DEFAULT 0,
+    expires_at  TEXT,
+    created_at  TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
+);
+CREATE INDEX invites_guild_idx ON invites (guild_id, created_at DESC);
+CREATE INDEX invites_expires_idx ON invites (expires_at);
+
+-- +goose Down
+DROP TABLE invites;
+DROP TRIGGER messages_fts_update;
+DROP TRIGGER messages_fts_delete;
+DROP TRIGGER messages_fts_insert;
+DROP TABLE messages_fts;
+DROP TABLE files;
+DROP TABLE channel_read_states;
+DROP TABLE message_reactions;
+DROP TABLE messages;