diff --git a/Makefile.cbm b/Makefile.cbm
index b78018c1..9620c126 100644
--- a/Makefile.cbm
+++ b/Makefile.cbm
@@ -461,6 +461,7 @@ TEST_REPRO_SRCS = \
     tests/repro/repro_issue787.c \
     tests/repro/repro_issue842.c \
     tests/repro/repro_issue964.c \
+    tests/repro/repro_issue769.c \
     tests/repro/repro_invariant_calls.c \
     tests/repro/repro_invariant_graph.c \
     tests/repro/repro_invariant_breadth.c \
diff --git a/src/pipeline/pipeline.c b/src/pipeline/pipeline.c
index 9f363922..2f481e89 100644
--- a/src/pipeline/pipeline.c
+++ b/src/pipeline/pipeline.c
@@ -1116,17 +1116,30 @@ static int try_incremental_or_delete_db(cbm_pipeline_t *p, cbm_file_info_t *file
     if (check_store && cbm_store_check_integrity(check_store)) {
         cbm_file_hash_t *hashes = NULL;
         int hash_count = 0;
+        int fmt = 0;
+
         cbm_store_get_file_hashes(check_store, p->project_name, &hashes, &hash_count);
         cbm_store_free_file_hashes(hashes, hash_count);
+        cbm_store_get_format_version(check_store, &fmt);
+
+        bool format_stale = (fmt != CBM_INDEX_FORMAT_VERSION);
         cbm_store_close(check_store);
-        if (hash_count > 0 && file_count <= hash_count + (hash_count / PAIR_LEN)) {
+
+        if (format_stale) {
+            if (hash_count > 0) {
+                char stored_buf[CBM_SZ_32];
+                snprintf(stored_buf, sizeof(stored_buf), "%d", fmt);
+                cbm_log_info("pipeline.route", "path", "format_change_reindex", "stored_format",
+                             stored_buf);
+            }
+            /* fall through to delete + full rebuild */
+        } else if (hash_count > 0 && file_count <= hash_count + (hash_count / PAIR_LEN)) {
             cbm_log_info("pipeline.route", "path", "incremental", "stored_hashes",
                          itoa_buf(hash_count));
             int rc = cbm_pipeline_run_incremental(p, db_path, files, file_count);
             free(db_path);
             return rc;
-        }
-        if (hash_count > 0) {
+        } else if (hash_count > 0) {
             cbm_log_info("pipeline.route", "path", "mode_change_reindex", "stored_hashes",
                          itoa_buf(hash_count), "discovered", itoa_buf(file_count));
         }
@@ -1226,6 +1239,9 @@ static int dump_and_persist_hashes(cbm_pipeline_t *p, const cbm_file_info_t *fil
     CBM_PROF_END("persist", "1_reopen", t_reopen);
     if (hash_store) {
         bool hash_records_complete = true;
+        if (cbm_store_set_format_version(hash_store, CBM_INDEX_FORMAT_VERSION) != CBM_STORE_OK) {
+            cbm_log_error("pipeline.err", "phase", "persist_format_version");
+        }
         CBM_PROF_START(t_delhash);
         if (cbm_store_delete_file_hashes(hash_store, p->project_name) != CBM_STORE_OK) {
             hash_records_complete = false;
diff --git a/src/pipeline/pipeline_incremental.c b/src/pipeline/pipeline_incremental.c
index 8b576697..3f8125f3 100644
--- a/src/pipeline/pipeline_incremental.c
+++ b/src/pipeline/pipeline_incremental.c
@@ -668,6 +668,13 @@ static void dump_and_persist(cbm_gbuf_t *gbuf, const char *db_path, const char *
         bool hash_records_complete = persist_hashes(hash_store, project, files, file_count,
                                                     mode_skipped, mode_skipped_count);
 
+        /* #769: cbm_writer_open truncates and rebuilds the DB file from
+         * scratch on every dump, so the format version written by the last
+         * full index is gone by the time we get here. */
+        if (cbm_store_set_format_version(hash_store, CBM_INDEX_FORMAT_VERSION) != CBM_STORE_OK) {
+            cbm_log_error("incremental.err", "msg", "persist_format_version", "project", project);
+        }
+
         /* Coverage rows (#963): re-write the merged set into the rebuilt DB
          * (AFTER hashes, so the deleted-file prune sees the live file set). */
         cbm_project_t project_info = {0};
diff --git a/src/store/store.c b/src/store/store.c
index 112d5ea7..40dd0bc7 100644
--- a/src/store/store.c
+++ b/src/store/store.c
@@ -2749,6 +2749,36 @@ int cbm_store_list_files(cbm_store_t *s, const char *project, char ***out, int *
     return CBM_STORE_OK;
 }
 
+/* ── Index format version (PRAGMA user_version) ─────────────────── */
+
+int cbm_store_get_format_version(cbm_store_t *s, int *out) {
+    if (!s || !s->db || !out) {
+        return CBM_STORE_ERR;
+    }
+    *out = 0;
+    sqlite3_stmt *stmt = NULL;
+    if (sqlite3_prepare_v2(s->db, "PRAGMA user_version;", CBM_NOT_FOUND, &stmt, NULL) !=
+        SQLITE_OK) {
+        return CBM_STORE_ERR;
+    }
+    if (sqlite3_step(stmt) == SQLITE_ROW) {
+        *out = sqlite3_column_int(stmt, 0);
+    }
+    sqlite3_finalize(stmt);
+    return CBM_STORE_OK;
+}
+
+/* PRAGMA values cannot be bound; format the integer constant in. Writes, so
+ * only call on a read-write connection (never from configure_pragmas). */
+int cbm_store_set_format_version(cbm_store_t *s, int version) {
+    if (!s || !s->db) {
+        return CBM_STORE_ERR;
+    }
+    char sql[ST_BUF_64];
+    snprintf(sql, sizeof(sql), "PRAGMA user_version = %d;", version);
+    return exec_sql(s, sql);
+}
+
 /* ── Node neighbor names ──────────────────────────────────────── */
 
 static int query_neighbor_names(sqlite3 *db, const char *sql, int64_t node_id, int limit,
diff --git a/src/store/store.h b/src/store/store.h
index 963837f8..e08b51e7 100644
--- a/src/store/store.h
+++ b/src/store/store.h
@@ -23,6 +23,7 @@ typedef struct cbm_store cbm_store_t;
 #define CBM_STORE_OK 0
 #define CBM_STORE_ERR (-1)
 #define CBM_STORE_NOT_FOUND (-2)
+#define CBM_INDEX_FORMAT_VERSION 1
 
 /* ── Data structures ────────────────────────────────────────────── */
 
@@ -77,6 +78,13 @@ void cbm_store_node_degree(cbm_store_t *s, int64_t node_id, int *in_deg, int *ou
  * Returns CBM_STORE_OK or CBM_STORE_ERR. */
 int cbm_store_list_files(cbm_store_t *s, const char *project, char ***out, int *count);
 
+/* Persisted index-format identity. Bump when a change alters the QN scheme
+ * or node identity of an already-written graph, so an old DB is routed
+ * through the full-reindex path instead of producing a mixed graph.
+ * 1 = File QNs keep the file extension (#769). */
+int cbm_store_get_format_version(cbm_store_t *s, int *out);
+int cbm_store_set_format_version(cbm_store_t *s, int version);
+
 /* Get caller/callee names for a node (CALLS/HTTP_CALLS/ASYNC_CALLS edges).
  * Returns 0 on success. Caller must free each out_callers[i]/out_callees[i]
  * and the arrays themselves. */
diff --git a/tests/repro/repro_issue769.c b/tests/repro/repro_issue769.c
new file mode 100644
index 00000000..ce888497
--- /dev/null
+++ b/tests/repro/repro_issue769.c
@@ -0,0 +1,189 @@
+/*
+ * repro_issue769.c -- Reproduce-first / regression guard for bug #769.
+ *
+ * Issue #769: "Angular component sibling files (ts/html/scss) merged into one
+ *              File node; search_code silently incomplete"
+ *
+ * ROOT CAUSE:
+ *   cbm_pipeline_fqn_compute (pipeline/fqn.c) called strip_file_extension()
+ *   unconditionally, removing only the FINAL extension from the last path
+ *   component. For a component's sibling files that is the only distinguishing
+ *   part, so badge.component.ts / .html / .scss all produced one QN:
+ *       proj.badge.badge.component.__file__
+ *   cbm_gbuf_upsert_node keys on QN, so the three files collapse into a single
+ *   File node; only one path survives (the canonical content rule from #787
+ *   picks the lexicographically smallest file_path, i.e. .html).
+ *
+ *   The search impact follows from cbm_store_list_files:
+ *       SELECT DISTINCT file_path FROM nodes WHERE ...
+ *   (no label filter — any node carrying the path makes the file searchable).
+ *   write_scoped_filelist feeds that list to `xargs -0 grep`, so a file with no
+ *   node carrying its exact path is NEVER OPENED. Templates and stylesheets
+ *   produce no def nodes, so once they lose the QN collision they have no
+ *   fallback node and vanish from search with no truncation warning.
+ *
+ * FIX:
+ *   fqn.c: skip strip_file_extension when the caller passes the "__file__"
+ *   sentinel. File identity becomes one node per actual source/template/style
+ *   file. Symbol and module QNs are unchanged.
+ *
+ * FIXTURE DESIGN:
+ *   One component, three siblings, each containing the marker:
+ *     badge/badge.component.ts    (parsed — yields a Class + Method)
+ *     badge/badge.component.html  (not parsed — no def nodes)
+ *     badge/badge.component.scss  (not parsed — no def nodes)
+ *   Plus an unrelated help.html whose stem collides with nothing, as a control:
+ *   it must be searchable both before and after the fix.
+ *
+ * WHY RED on buggy HEAD:
+ *   - File-node count is 2 (one merged component node + help.html), not 4.
+ *   - list_files omits badge.component.scss and badge.component.ts, so grep
+ *     never opens them and the marker set comes back short.
+ *   - The surviving node's extension does not match its file_path.
+ */
+#include <foundation/compat.h>
+#include "foundation/log.h"
+#include "test_framework.h"
+#include "repro_harness.h"
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+static const char k_badge_ts[] =
+    "export class BadgeComponent {\n"
+    "  isHighlighted() { return true; } /* repro-marker */\n"
+    "}\n";
+
+static const char k_badge_html[] = "<div class=\"badge\">repro-marker</div>\n";
+
+static const char k_badge_scss[] = ".badge { color: red; /* repro-marker */ }\n";
+
+static const char k_help_html[] = "<p>repro-marker</p>\n";
+
+static const RFile k_files[] = {
+    {"badge/badge.component.ts", k_badge_ts},
+    {"badge/badge.component.html", k_badge_html},
+    {"badge/badge.component.scss", k_badge_scss},
+    {"standalone/help.html", k_help_html},
+};
+static const int k_nfiles = (int)(sizeof(k_files) / sizeof(k_files[0]));
+
+static char g_log_buf[8192];
+static size_t g_log_len;
+
+static void capture_sink(const char *line) {
+    size_t n = strlen(line);
+    if (g_log_len + n + 1 < sizeof(g_log_buf)) {
+        memcpy(g_log_buf + g_log_len, line, n);
+        g_log_len += n;
+        g_log_buf[g_log_len++] = '\n';
+        g_log_buf[g_log_len] = '\0';
+    }
+}
+
+static void capture_reset(void) {
+    g_log_len = 0;
+    g_log_buf[0] = '\0';
+}
+
+TEST(repro_issue769_component_siblings_distinct_and_searchable) {
+    RProj lp;
+    cbm_store_t *store = rh_index_files(&lp, k_files, k_nfiles);
+    ASSERT_NOT_NULL(store);
+
+    /* 1. One File node per file on disk — not one per component stem. */
+    ASSERT_EQ(rh_count_label(store, lp.project, "File"), k_nfiles);
+
+    /* 2. Every fixture file reaches the scoped grep list. */
+    char **listed = NULL;
+    int nlisted = 0;
+    ASSERT_EQ(cbm_store_list_files(store, lp.project, &listed, &nlisted), CBM_STORE_OK);
+    for (int i = 0; i < k_nfiles; i++) {
+        bool found = false;
+        for (int j = 0; j < nlisted; j++) {
+            if (listed[j] && strcmp(listed[j], k_files[i].name) == 0) {
+                found = true;
+                break;
+            }
+        }
+        ASSERT(found);
+    }
+    for (int j = 0; j < nlisted; j++) {
+        free(listed[j]);
+    }
+    free(listed);
+
+    /* 3. search_code reaches every sibling. */
+    char args[700];
+    snprintf(args, sizeof(args),
+             "{\"project\":\"%s\",\"pattern\":\"repro-marker\",\"mode\":\"files\"}", lp.project);
+    char *resp = cbm_mcp_handle_tool(lp.srv, "search_code", args);
+    ASSERT_NOT_NULL(resp);
+    for (int i = 0; i < k_nfiles; i++) {
+        ASSERT(strstr(resp, k_files[i].name) != NULL);
+    }
+    free(resp);
+
+    rh_cleanup(&lp, store);
+    PASS();
+}
+
+/*
+ * #769 upgrade path: an index written before the File-QN format change holds
+ * collided File identities. Refreshing it incrementally would give touched
+ * files new-format QNs while untouched files keep the old ones, a mixed
+ * graph. try_incremental_or_delete_db must route a stale-format index through
+ * the full-reindex path exactly once, and the rebuilt index must not force a
+ * second rebuild on the next unchanged run.
+ */
+TEST(repro_issue769_stale_format_forces_one_rebuild) {
+    RProj lp;
+    cbm_store_t *store = rh_index_files(&lp, k_files, k_nfiles);
+    ASSERT_NOT_NULL(store);
+
+    /* Simulate a pre-change index. */
+    ASSERT_EQ(cbm_store_set_format_version(store, 0), CBM_STORE_OK);
+    cbm_store_close(store);
+
+    char args[700];
+    snprintf(args, sizeof(args), "{\"repo_path\":\"%s\"}", lp.tmpdir);
+
+    /* Run 1: stale format → forced full rebuild. */
+    capture_reset();
+    cbm_log_set_sink_ex(capture_sink, CBM_LOG_SINK_TEE);
+    char *resp = cbm_mcp_handle_tool(lp.srv, "index_repository", args);
+    cbm_log_set_sink(NULL);
+    ASSERT_NOT_NULL(resp);
+    free(resp);
+    ASSERT(strstr(g_log_buf, "format_change_reindex") != NULL);
+
+    /* Rebuild produced distinct File nodes and stamped the current format. */
+    store = cbm_store_open_path(lp.dbpath);
+    ASSERT_NOT_NULL(store);
+    ASSERT_EQ(rh_count_label(store, lp.project, "File"), k_nfiles);
+    int fmt = -1;
+    ASSERT_EQ(cbm_store_get_format_version(store, &fmt), CBM_STORE_OK);
+    ASSERT_EQ(fmt, CBM_INDEX_FORMAT_VERSION);
+    cbm_store_close(store);
+
+    /* Run 2: unchanged, current format → no second rebuild. */
+    capture_reset();
+    cbm_log_set_sink_ex(capture_sink, CBM_LOG_SINK_TEE);
+    resp = cbm_mcp_handle_tool(lp.srv, "index_repository", args);
+    cbm_log_set_sink(NULL);
+    ASSERT_NOT_NULL(resp);
+    free(resp);
+    ASSERT(strstr(g_log_buf, "format_change_reindex") == NULL);
+    ASSERT(strstr(g_log_buf, "path=incremental") != NULL);
+
+    store = cbm_store_open_path(lp.dbpath);
+    ASSERT_NOT_NULL(store);
+    ASSERT_EQ(rh_count_label(store, lp.project, "File"), k_nfiles);
+    rh_cleanup(&lp, store);
+    PASS();
+}
+
+SUITE(repro_issue769) {
+    RUN_TEST(repro_issue769_component_siblings_distinct_and_searchable);
+    RUN_TEST(repro_issue769_stale_format_forces_one_rebuild);
+}
\ No newline at end of file
diff --git a/tests/repro/repro_main.c b/tests/repro/repro_main.c
index fe0ac29f..003c357f 100644
--- a/tests/repro/repro_main.c
+++ b/tests/repro/repro_main.c
@@ -83,6 +83,7 @@ extern void suite_repro_issue581(void);
 extern void suite_repro_issue787(void);
 extern void suite_repro_issue842(void);
 extern void suite_repro_issue964(void);
+extern void suite_repro_issue769(void); 
 /* NEW bugs found by the discovery sweep */
 extern void suite_repro_new_ts_class_field_arrow(void);
 extern void suite_repro_new_py_tuple_unpack(void);
@@ -167,6 +168,7 @@ int main(void) {
     RUN_SUITE(repro_new_cypher_limit_zero);
     RUN_SUITE(repro_issue363);
     RUN_SUITE(repro_issue581);
+    RUN_SUITE(repro_issue769);
     RUN_SUITE(repro_issue787);
     RUN_SUITE(repro_issue842);
     RUN_SUITE(repro_issue964);
diff --git a/tests/test_fqn.c b/tests/test_fqn.c
index d2163424..5d565f8d 100644
--- a/tests/test_fqn.c
+++ b/tests/test_fqn.c
@@ -89,6 +89,77 @@ TEST(fqn_compute_basic_rs) {
     PASS();
 }
 
+TEST(fqn_compute_file_sibling_distinct) {
+    char *ts = cbm_pipeline_fqn_compute("proj", "app/badge/badge.component.ts", "__file__");
+    char *html = cbm_pipeline_fqn_compute("proj", "app/badge/badge.component.html", "__file__");
+    char *scss = cbm_pipeline_fqn_compute("proj", "app/badge/badge.component.scss", "__file__");
+    ASSERT_NOT_NULL(ts);
+    ASSERT_NOT_NULL(html);
+    ASSERT_NOT_NULL(scss);
+    ASSERT_STR_NEQ(ts, html);
+    ASSERT_STR_NEQ(ts, scss);
+    ASSERT_STR_NEQ(html, scss);
+    free(ts);
+    free(html);
+    free(scss);
+    PASS();
+}
+
+TEST(fqn_compute_symbol_still_strips) {
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", "app/badge/badge.component.ts", "BadgeComponent"),
+               "proj.app.badge.badge.component.BadgeComponent");
+    PASS();
+}
+
+TEST(fqn_module_siblings_still_share) {
+    ASSERT_FQN(cbm_pipeline_fqn_module("proj", "app/badge/badge.component.ts"),
+               "proj.app.badge.badge.component");
+    ASSERT_FQN(cbm_pipeline_fqn_module("proj", "app/badge/badge.component.html"),
+               "proj.app.badge.badge.component");
+    PASS();
+}
+
+/* #769: exact __file__ QNs for component siblings. */
+TEST(fqn_compute_file_sibling_exact) {
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", "app/badge/badge.component.ts", "__file__"),
+               "proj.app.badge.badge.component.ts.__file__");
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", "app/badge/badge.component.html", "__file__"),
+               "proj.app.badge.badge.component.html.__file__");
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", "app/badge/badge.component.scss", "__file__"),
+               "proj.app.badge.badge.component.scss.__file__");
+    PASS();
+}
+
+TEST(fqn_compute_file_multi_extension) {
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", "app/badge/badge.spec.ts", "__file__"),
+               "proj.app.badge.badge.spec.ts.__file__");
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", "archive.tar.gz", "__file__"),
+               "proj.archive.tar.gz.__file__");
+    PASS();
+}
+
+TEST(fqn_compute_file_no_extension) {
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", "Makefile", "__file__"),
+               "proj.Makefile.__file__");
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", "LICENSE", "__file__"),
+               "proj.LICENSE.__file__");
+    PASS();
+}
+
+TEST(fqn_compute_file_dotfile) {
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", ".gitignore", "__file__"),
+               "proj..gitignore.__file__");
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", "config/.env", "__file__"),
+               "proj.config..env.__file__");
+    PASS();
+}
+
+TEST(fqn_compute_file_index_ts) {
+    ASSERT_FQN(cbm_pipeline_fqn_compute("proj", "app/index.ts", "__file__"),
+           "proj.app.index.ts.__file__");
+    PASS();
+}
+
 /* ── Nested paths ─────────────────────────────────────────────── */
 
 TEST(fqn_compute_nested_two_levels) {
@@ -595,6 +666,14 @@ SUITE(fqn) {
     RUN_TEST(fqn_file_qn_distinguishes_same_stem_header_source_issue964);
     RUN_TEST(fqn_module_qn_still_strips_extension);
     RUN_TEST(fqn_compute_basic_rs);
+    RUN_TEST(fqn_compute_file_sibling_distinct);
+    RUN_TEST(fqn_compute_symbol_still_strips);
+    RUN_TEST(fqn_module_siblings_still_share);
+    RUN_TEST(fqn_compute_file_sibling_exact);
+    RUN_TEST(fqn_compute_file_multi_extension);
+    RUN_TEST(fqn_compute_file_no_extension);
+    RUN_TEST(fqn_compute_file_dotfile);
+    RUN_TEST(fqn_compute_file_index_ts);
 
     /* fqn_compute: nested paths */
     RUN_TEST(fqn_compute_nested_two_levels);