diff --git a/internal/cbm/extract_unified.c b/internal/cbm/extract_unified.c
index fd900b28e..20e294c93 100644
--- a/internal/cbm/extract_unified.c
+++ b/internal/cbm/extract_unified.c
@@ -1646,6 +1646,27 @@ static bool is_actual_import_boundary(CBMExtractCtx *ctx, TSNode node, const CBM
     char *name = ts_node_is_null(head) ? NULL : cbm_node_text(ctx->arena, head, ctx->source);
 
     switch (ctx->language) {
+    case CBM_LANG_JAVASCRIPT:
+    case CBM_LANG_TYPESCRIPT:
+    case CBM_LANG_TSX:
+        if (strcmp(kind, "export_statement") == 0) {
+            /* An export is an import CONTEXT only in its re-export forms:
+             * `export ... from 'mod'` (source field) or a bare specifier list
+             * `export { a, b }` with no declaration. An export OF a declaration
+             * must not put the declaration's body behind inside_import — the
+             * old kind-blacklist (is_export_of_declaration) missed the TS-only
+             * forms (ambient_declaration, function_signature,
+             * module_declaration), so declare-heavy code (.d.ts, baselines,
+             * `export namespace`) ran whole subtrees as import context:
+             * suppressed usages plus per-identifier ancestor walks. Positive
+             * detection replaces the blacklist. */
+            if (!ts_node_is_null(ts_node_child_by_field_name(node, TS_FIELD("source")))) {
+                return true;
+            }
+            return !ts_node_is_null(cbm_find_child_by_kind(node, "export_clause")) &&
+                   ts_node_is_null(ts_node_child_by_field_name(node, TS_FIELD("declaration")));
+        }
+        return true; /* import_statement / import / require / extends: unchanged */
     case CBM_LANG_CSHARP:
         /* cs_import_types also lists namespace_declaration (so the import pass
          * can map namespace names) and using_statement (C#'s RAII block, a
diff --git a/src/store/store.c b/src/store/store.c
index d91346e67..4e2b12d62 100644
--- a/src/store/store.c
+++ b/src/store/store.c
@@ -2668,6 +2668,20 @@ static void cov_failure_fingerprint(const cbm_coverage_row_t *rows, int count,
     out[CBM_SHA256_HEX_LEN] = 0;
 }
 
+static void cov_dir_ids_free_entry(const char *key, void *val, void *ud) {
+    (void)ud;
+    free((char *)key);
+    free(val);
+}
+
+static void cov_dir_ids_free(CBMHashTable *ht) {
+    if (!ht) {
+        return;
+    }
+    cbm_ht_foreach(ht, cov_dir_ids_free_entry, NULL);
+    cbm_ht_free(ht);
+}
+
 static int cov_rebuild_shadow_graph(cbm_store_t *s, const char *project) {
     char covproj[CBM_SZ_512];
     cbm_store_coverage_shadow_project(covproj, sizeof(covproj), project);
@@ -2765,6 +2779,12 @@ static int cov_rebuild_shadow_graph(cbm_store_t *s, const char *project) {
         return CBM_STORE_ERR;
     }
 
+    /* Directory nodes repeat massively across failure rows (13k baseline files
+     * under one tests/ subtree meant ~80k redundant upsert/edge round-trips —
+     * 9.1 s of a 9.2 s coverage_replace on the TypeScript corpus). Dedup them
+     * in-memory for the rebuild: first sight of a directory creates its node
+     * and containment edge; every later file under it is a hash hit. */
+    CBMHashTable *dir_ids = cbm_ht_create(CBM_SZ_256);
     for (int i = 0; i < count; i++) {
         const char *rel = rows[i].rel_path;
         if (!rel || !rel[0]) {
@@ -2787,6 +2807,12 @@ static int cov_rebuild_shadow_graph(cbm_store_t *s, const char *project) {
             /* Truncate at this slash → pathbuf is the directory prefix; the
              * upsert binds copies, so restore the slash right after. */
             *p = '\0';
+            int64_t *cached = dir_ids ? (int64_t *)cbm_ht_get(dir_ids, pathbuf) : NULL;
+            if (cached) {
+                parent = *cached;
+                *p = '/';
+                continue;
+            }
             const char *seg = strrchr(pathbuf, '/');
             cbm_node_t folder = {.project = covproj,
                                  .label = "Folder",
@@ -2795,8 +2821,9 @@ static int cov_rebuild_shadow_graph(cbm_store_t *s, const char *project) {
                                  .file_path = pathbuf,
                                  .properties_json = "{}"};
             int64_t fid = cbm_store_upsert_node(s, &folder);
-            *p = '/';
             if (fid <= 0) {
+                *p = '/';
+                cov_dir_ids_free(dir_ids);
                 cbm_store_free_coverage(rows, count);
                 return CBM_STORE_ERR;
             }
@@ -2806,9 +2833,24 @@ static int cov_rebuild_shadow_graph(cbm_store_t *s, const char *project) {
                             .type = "CONTAINS_FOLDER",
                             .properties_json = "{}"};
             if (cbm_store_insert_edge(s, &e) <= 0) {
+                *p = '/';
+                cov_dir_ids_free(dir_ids);
                 cbm_store_free_coverage(rows, count);
                 return CBM_STORE_ERR;
             }
+            if (dir_ids) {
+                int64_t *idv = (int64_t *)malloc(sizeof(*idv));
+                if (idv) {
+                    *idv = fid;
+                    char *kdup = strdup(pathbuf);
+                    if (kdup) {
+                        cbm_ht_set(dir_ids, kdup, idv);
+                    } else {
+                        free(idv);
+                    }
+                }
+            }
+            *p = '/';
             parent = fid;
         }
 
@@ -2826,6 +2868,7 @@ static int cov_rebuild_shadow_graph(cbm_store_t *s, const char *project) {
                            .properties_json = props};
         int64_t file_id = cbm_store_upsert_node(s, &file);
         if (file_id <= 0) {
+            cov_dir_ids_free(dir_ids);
             cbm_store_free_coverage(rows, count);
             return CBM_STORE_ERR;
         }
@@ -2835,10 +2878,12 @@ static int cov_rebuild_shadow_graph(cbm_store_t *s, const char *project) {
                         .type = "CONTAINS_FILE",
                         .properties_json = "{}"};
         if (cbm_store_insert_edge(s, &e) <= 0) {
+            cov_dir_ids_free(dir_ids);
             cbm_store_free_coverage(rows, count);
             return CBM_STORE_ERR;
         }
     }
+    cov_dir_ids_free(dir_ids);
     cbm_store_free_coverage(rows, count);
     {
         sqlite3_stmt *set = NULL;
@@ -2862,6 +2907,15 @@ int cbm_store_coverage_replace_ex(cbm_store_t *s, const char *project,
     if (exec_sql(s, "BEGIN;") != CBM_STORE_OK) {
         return CBM_STORE_ERR;
     }
+    /* Sub-block timings (publish.timing style): coverage_replace measured 9 s
+     * on the TypeScript corpus and the caller-level block could not say WHY —
+     * delete, 13k row inserts with large error_ranges payloads, the NOT-IN
+     * prune, meta, and COMMIT are very different suspects. */
+    struct timespec cov_t0;
+    struct timespec cov_t1;
+    long cov_ms[5] = {0, 0, 0, 0, 0};
+    long long cov_detail_bytes = 0;
+    cbm_clock_gettime(CLOCK_MONOTONIC, &cov_t0);
     sqlite3_stmt *del = NULL;
     if (sqlite3_prepare_v2(s->db, "DELETE FROM index_coverage WHERE project = ?1;", CBM_NOT_FOUND,
                            &del, NULL) != SQLITE_OK) {
@@ -2877,6 +2931,10 @@ int cbm_store_coverage_replace_ex(cbm_store_t *s, const char *project,
         (void)exec_sql(s, "ROLLBACK;");
         return CBM_STORE_ERR;
     }
+    cbm_clock_gettime(CLOCK_MONOTONIC, &cov_t1);
+    cov_ms[0] =
+        (cov_t1.tv_sec - cov_t0.tv_sec) * 1000 + (cov_t1.tv_nsec - cov_t0.tv_nsec) / 1000000;
+    cov_t0 = cov_t1;
     sqlite3_stmt *ins = NULL;
     if (sqlite3_prepare_v2(
             s->db,
@@ -2894,6 +2952,7 @@ int cbm_store_coverage_replace_ex(cbm_store_t *s, const char *project,
         bind_text(ins, SKIP_ONE, project);
         bind_text(ins, ST_COL_2, rows[i].rel_path);
         bind_text(ins, ST_COL_3, rows[i].kind);
+        cov_detail_bytes += rows[i].detail ? (long long)strlen(rows[i].detail) : 0;
         bind_text(ins, CBM_SZ_4, rows[i].detail ? rows[i].detail : "");
         if (sqlite3_step(ins) != SQLITE_DONE) {
             store_set_error_sqlite(s, "coverage insert");
@@ -2904,6 +2963,10 @@ int cbm_store_coverage_replace_ex(cbm_store_t *s, const char *project,
         sqlite3_reset(ins);
     }
     sqlite3_finalize(ins);
+    cbm_clock_gettime(CLOCK_MONOTONIC, &cov_t1);
+    cov_ms[1] =
+        (cov_t1.tv_sec - cov_t0.tv_sec) * 1000 + (cov_t1.tv_nsec - cov_t0.tv_nsec) / 1000000;
+    cov_t0 = cov_t1;
     /* Prune FAILURE rows for files no longer known to the index (deleted from
      * the repo): file_hashes is the authoritative live-file set after
      * persist. By-design not_indexed_* rows are exempt — deliberately
@@ -2927,6 +2990,10 @@ int cbm_store_coverage_replace_ex(cbm_store_t *s, const char *project,
         (void)exec_sql(s, "ROLLBACK;");
         return CBM_STORE_ERR;
     }
+    cbm_clock_gettime(CLOCK_MONOTONIC, &cov_t1);
+    cov_ms[2] =
+        (cov_t1.tv_sec - cov_t0.tv_sec) * 1000 + (cov_t1.tv_nsec - cov_t0.tv_nsec) / 1000000;
+    cov_t0 = cov_t1;
 
     if (meta) {
         char recorded_at[CBM_SZ_64];
@@ -3002,7 +3069,33 @@ int cbm_store_coverage_replace_ex(cbm_store_t *s, const char *project,
         (void)exec_sql(s, "ROLLBACK;");
         return CBM_STORE_ERR;
     }
-    return exec_sql(s, "COMMIT;");
+    cbm_clock_gettime(CLOCK_MONOTONIC, &cov_t1);
+    cov_ms[3] =
+        (cov_t1.tv_sec - cov_t0.tv_sec) * 1000 + (cov_t1.tv_nsec - cov_t0.tv_nsec) / 1000000;
+    cov_t0 = cov_t1;
+    int commit_rc = exec_sql(s, "COMMIT;");
+    cbm_clock_gettime(CLOCK_MONOTONIC, &cov_t1);
+    cov_ms[4] =
+        (cov_t1.tv_sec - cov_t0.tv_sec) * 1000 + (cov_t1.tv_nsec - cov_t0.tv_nsec) / 1000000;
+    {
+        char b0[ST_BUF_64];
+        char b1[ST_BUF_64];
+        char b2[ST_BUF_64];
+        char b3[ST_BUF_64];
+        char b4[ST_BUF_64];
+        char bn[ST_BUF_64];
+        char bb[ST_BUF_64];
+        snprintf(b0, sizeof(b0), "%ld", cov_ms[0]);
+        snprintf(b1, sizeof(b1), "%ld", cov_ms[1]);
+        snprintf(b2, sizeof(b2), "%ld", cov_ms[2]);
+        snprintf(b3, sizeof(b3), "%ld", cov_ms[3]);
+        snprintf(b4, sizeof(b4), "%ld", cov_ms[4]);
+        snprintf(bn, sizeof(bn), "%d", count);
+        snprintf(bb, sizeof(bb), "%lld", cov_detail_bytes);
+        cbm_log_info("publish.timing.coverage", "del", b0, "rows", b1, "prune", b2, "meta", b3,
+                     "commit", b4, "row_count", bn, "detail_bytes", bb);
+    }
+    return commit_rc;
 }
 
 int cbm_store_coverage_replace(cbm_store_t *s, const char *project, const cbm_coverage_row_t *rows,