diff --git a/common/arg.cpp b/common/arg.cpp
index c442896..687fda2 100644
--- a/common/arg.cpp
+++ b/common/arg.cpp
@@ -817,6 +817,15 @@ static bool common_params_parse_ex(int argc, char ** argv, common_params_context
     if (params.load_mode == LLAMA_LOAD_MODE_LONGHAUL && params.longhaul_cache_bytes == 0) {
         throw std::invalid_argument("error: --longhaul requires --longhaul-cache N\n");
     }
+    if (params.tokenizer_longhaul != (params.tokenizer_longhaul_cache_bytes != 0)) {
+        throw std::invalid_argument(
+            params.tokenizer_longhaul
+                ? "error: --tokenizer-longhaul requires --tokenizer-longhaul-cache N\n"
+                : "error: --tokenizer-longhaul-cache requires --tokenizer-longhaul\n");
+    }
+    if (params.tokenizer_longhaul && params.token_cache_size_mib == 0) {
+        throw std::invalid_argument("error: --tokenizer-longhaul requires an enabled persistent token cache\n");
+    }
 
     postprocess_cpu_params(params.cpuparams,       nullptr);
     postprocess_cpu_params(params.cpuparams_batch, &params.cpuparams);
@@ -2646,6 +2655,23 @@ common_params_context common_params_parser_init(common_params & params, llama_ex
             params.longhaul_cache_bytes = uint64_t(value) * 1024 * 1024 * 1024;
         }
     ).set_env("LLAMA_ARG_LONGHAUL_CACHE"));
+    add_opt(common_arg(
+        {"--tokenizer-longhaul"},
+        "build and page the Qwen3.5/Laguna tokenizer through a bounded cache",
+        [](common_params & params) {
+            params.tokenizer_longhaul = true;
+        }
+    ).set_env("LLAMA_ARG_TOKENIZER_LONGHAUL"));
+    add_opt(common_arg(
+        {"--tokenizer-longhaul-cache"}, "N",
+        "tokenizer-longhaul RAM cache size in MiB",
+        [](common_params & params, int value) {
+            if (value <= 0) {
+                throw std::invalid_argument("tokenizer-longhaul cache size must be positive");
+            }
+            params.tokenizer_longhaul_cache_bytes = uint64_t(value) * 1024 * 1024;
+        }
+    ).set_env("LLAMA_ARG_TOKENIZER_LONGHAUL_CACHE"));
     add_opt(common_arg(
         {"--numa"}, "TYPE",
         "attempt optimizations that help on some NUMA systems\n"
diff --git a/common/common.cpp b/common/common.cpp
index 97dea3d..35e2001 100644
--- a/common/common.cpp
+++ b/common/common.cpp
@@ -1592,6 +1592,8 @@ struct llama_model_params common_model_params_to_llama(common_params & params) {
     mparams.split_mode      = params.split_mode;
     mparams.load_mode       = params.load_mode;
     mparams.longhaul_cache_bytes = params.longhaul_cache_bytes;
+    mparams.tokenizer_longhaul = params.tokenizer_longhaul;
+    mparams.tokenizer_longhaul_cache_bytes = params.tokenizer_longhaul_cache_bytes;
     mparams.tensor_split    = params.tensor_split;
     mparams.check_tensors   = params.check_tensors;
     mparams.use_extra_bufts = !params.no_extra_bufts;
diff --git a/common/common.h b/common/common.h
index c56699a..ba04319 100644
--- a/common/common.h
+++ b/common/common.h
@@ -486,6 +486,8 @@ struct common_params {
     enum llama_split_mode split_mode = LLAMA_SPLIT_MODE_LAYER; // how to split the model across GPUs
     enum llama_load_mode  load_mode  = LLAMA_LOAD_MODE_MMAP; // how to load the model
     uint64_t longhaul_cache_bytes = 0;
+    bool tokenizer_longhaul = false;
+    uint64_t tokenizer_longhaul_cache_bytes = 0;
 
     common_cpu_params cpuparams;
     common_cpu_params cpuparams_batch;
diff --git a/docs/token-cache.md b/docs/token-cache.md
index af2d0c3..b7a00b2 100644
--- a/docs/token-cache.md
+++ b/docs/token-cache.md
@@ -30,3 +30,24 @@ call `llama_token_cache_flush()`.
 
 The 5 GiB limit accounts for logical entry payloads. SQLite metadata and bounded
 journal files are not included.
+
+## Tokenizer longhaul
+
+Qwen3.5 MoE and Laguna models can move their reverse-token and BPE-merge indexes
+into a persistent, disk-backed index while keeping a bounded lookup working set:
+
+```text
+--tokenizer-longhaul
+--tokenizer-longhaul-cache N
+```
+
+`N` is the application-owned lookup cache budget in MiB and is required when
+the mode is enabled. The mode is independent of model `--longhaul`, so the two
+can be used together. The finite tokenizer index builds in the background while
+model loading continues. If tokenizer work arrives first, it waits for atomic
+index publication; build or storage failures are reported instead of silently
+falling back to an unbounded tokenizer.
+
+The persistent index uses the directory selected by `--token-cache-dir` and is
+subject to `--token-cache-size`. Tokenized-text results continue to be cached
+on demand and therefore do not have a finite completion point.
diff --git a/include/llama.h b/include/llama.h
index f961ab3..41b58e9 100644
--- a/include/llama.h
+++ b/include/llama.h
@@ -360,6 +360,8 @@ extern "C" {
         bool no_alloc;        // only load metadata and simulate memory allocations
 
         uint64_t longhaul_cache_bytes; // routed expert cache size for LLAMA_LOAD_MODE_LONGHAUL
+        bool tokenizer_longhaul;       // page Qwen3.5/Laguna tokenizer indexes through a bounded cache
+        uint64_t tokenizer_longhaul_cache_bytes; // tokenizer-longhaul RAM cache budget
     };
 
     struct llama_sampler_seq_config {
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 6fb9f12..4e8262d 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -38,6 +38,7 @@ add_library(llama
             llama-quant.cpp
             llama-sampler.cpp
             llama-token-cache.cpp
+            llama-tokenizer-longhaul.cpp
             llama-vocab.cpp
             unicode-data.cpp
             unicode.cpp
diff --git a/src/llama-model.cpp b/src/llama-model.cpp
index 67ee21e..42be071 100644
--- a/src/llama-model.cpp
+++ b/src/llama-model.cpp
@@ -1249,7 +1249,7 @@ void llama_model_base::load_hparams(llama_model_loader & ml) {
 void llama_model_base::load_vocab(llama_model_loader & ml) {
     const auto kv = LLM_KV(arch);
 
-    vocab.load(ml, kv);
+    vocab.load(ml, kv, params.tokenizer_longhaul, params.tokenizer_longhaul_cache_bytes);
 }
 
 bool llama_model_base::load_tensors(llama_model_loader & ml) {
@@ -2380,6 +2380,8 @@ llama_model_params llama_model_default_params() {
         /*.no_host                     =*/ false,
         /*.no_alloc                    =*/ false,
         /*.longhaul_cache_bytes        =*/ 0,
+        /*.tokenizer_longhaul          =*/ false,
+        /*.tokenizer_longhaul_cache_bytes =*/ 0,
     };
 
     return result;
diff --git a/src/llama-token-cache.cpp b/src/llama-token-cache.cpp
index 17fea0c..7c789b6 100644
--- a/src/llama-token-cache.cpp
+++ b/src/llama-token-cache.cpp
@@ -214,6 +214,10 @@ public:
         if (!ensure_open()) return params.capacity_bytes == 0;
         std::lock_guard<std::mutex> db_lock(db_mutex);
         if (sqlite3_exec(db, "DELETE FROM entries; PRAGMA incremental_vacuum;", nullptr, nullptr, nullptr) != SQLITE_OK) return db_error();
+        std::error_code ec;
+        fs::remove_all(fs::path(path).parent_path() / "tokenizer-indexes", ec);
+        if (ec) return false;
+        sqlite3_exec(db, "INSERT OR REPLACE INTO meta(key,value) VALUES('external_bytes',0)", nullptr, nullptr, nullptr);
         return true;
     }
 
@@ -239,6 +243,11 @@ public:
                 result.bytes_used = sqlite3_column_int64(stmt, 1);
             }
             sqlite3_finalize(stmt);
+            if (sqlite3_prepare_v2(db, "SELECT value FROM meta WHERE key='external_bytes'", -1, &stmt, nullptr) == SQLITE_OK &&
+                    sqlite3_step(stmt) == SQLITE_ROW) {
+                result.bytes_used += static_cast<uint64_t>(sqlite3_column_int64(stmt, 0));
+            }
+            sqlite3_finalize(stmt);
         }
         return result;
     }
@@ -247,6 +256,45 @@ public:
         if (hit) ++stats.tokenizer_hits; else ++stats.tokenizer_misses;
     }
 
+    std::string database_path() {
+        return ensure_open() ? path : std::string();
+    }
+
+    uint64_t capacity() const {
+        return params.capacity_bytes;
+    }
+
+    void set_external_bytes(uint64_t bytes) {
+        if (!ensure_open()) return;
+        std::lock_guard<std::mutex> db_lock(db_mutex);
+        sqlite3_exec(db, "BEGIN IMMEDIATE", nullptr, nullptr, nullptr);
+        sqlite3_stmt * stmt = nullptr;
+        sqlite3_prepare_v2(db, "INSERT OR REPLACE INTO meta(key,value) VALUES('external_bytes',?1)", -1, &stmt, nullptr);
+        sqlite3_bind_int64(stmt, 1, static_cast<sqlite3_int64>(bytes));
+        sqlite3_step(stmt);
+        sqlite3_finalize(stmt);
+
+        uint64_t total = 0;
+        sqlite3_prepare_v2(db, "SELECT COALESCE(SUM(size),0) FROM entries", -1, &stmt, nullptr);
+        if (sqlite3_step(stmt) == SQLITE_ROW) total = sqlite3_column_int64(stmt, 0);
+        sqlite3_finalize(stmt);
+        const uint64_t entry_capacity = bytes >= params.capacity_bytes ? 0 : params.capacity_bytes - bytes;
+        while (total > entry_capacity) {
+            uint64_t victim_size = 0;
+            sqlite3_prepare_v2(db, "SELECT size FROM entries ORDER BY last_access LIMIT 1", -1, &stmt, nullptr);
+            if (sqlite3_step(stmt) == SQLITE_ROW) victim_size = sqlite3_column_int64(stmt, 0);
+            sqlite3_finalize(stmt);
+            if (victim_size == 0 || sqlite3_exec(db,
+                    "DELETE FROM entries WHERE rowid=(SELECT rowid FROM entries ORDER BY last_access LIMIT 1)",
+                    nullptr, nullptr, nullptr) != SQLITE_OK) {
+                break;
+            }
+            total -= std::min(total, victim_size);
+            ++stats.evictions;
+        }
+        sqlite3_exec(db, "COMMIT", nullptr, nullptr, nullptr);
+    }
+
 private:
     static int64_t now_tick() {
         return std::chrono::duration_cast<std::chrono::microseconds>(
@@ -311,13 +359,22 @@ private:
         sqlite3_bind_int64(stmt, 1, static_cast<sqlite3_int64>(params.capacity_bytes));
         sqlite3_step(stmt);
         sqlite3_finalize(stmt);
+        uint64_t external_bytes = 0;
+        sqlite3_prepare_v2(db, "SELECT value FROM meta WHERE key='external_bytes'", -1, &stmt, nullptr);
+        if (sqlite3_step(stmt) == SQLITE_ROW) {
+            external_bytes = static_cast<uint64_t>(sqlite3_column_int64(stmt, 0));
+        }
+        sqlite3_finalize(stmt);
+        const uint64_t entry_capacity = external_bytes >= params.capacity_bytes
+            ? 0
+            : params.capacity_bytes - external_bytes;
         sqlite3_exec(db, "BEGIN IMMEDIATE", nullptr, nullptr, nullptr);
         while (true) {
             sqlite3_prepare_v2(db, "SELECT COALESCE(SUM(size),0) FROM entries", -1, &stmt, nullptr);
             uint64_t total = 0;
             if (sqlite3_step(stmt) == SQLITE_ROW) total = sqlite3_column_int64(stmt, 0);
             sqlite3_finalize(stmt);
-            if (total <= params.capacity_bytes) break;
+            if (total <= entry_capacity) break;
             if (sqlite3_exec(db,
                     "DELETE FROM entries WHERE rowid=(SELECT rowid FROM entries ORDER BY last_access LIMIT 1)",
                     nullptr, nullptr, nullptr) != SQLITE_OK) {
@@ -355,12 +412,19 @@ private:
         std::lock_guard<std::mutex> db_lock(db_mutex);
         if (sqlite3_exec(db, "BEGIN IMMEDIATE", nullptr, nullptr, nullptr) != SQLITE_OK) { db_error(); return; }
         uint64_t capacity = params.capacity_bytes;
+        uint64_t external_bytes = 0;
         sqlite3_stmt * capacity_stmt = nullptr;
         if (sqlite3_prepare_v2(db, "SELECT value FROM meta WHERE key='capacity'", -1, &capacity_stmt, nullptr) == SQLITE_OK &&
                 sqlite3_step(capacity_stmt) == SQLITE_ROW) {
             capacity = static_cast<uint64_t>(sqlite3_column_int64(capacity_stmt, 0));
         }
         sqlite3_finalize(capacity_stmt);
+        if (sqlite3_prepare_v2(db, "SELECT value FROM meta WHERE key='external_bytes'", -1, &capacity_stmt, nullptr) == SQLITE_OK &&
+                sqlite3_step(capacity_stmt) == SQLITE_ROW) {
+            external_bytes = static_cast<uint64_t>(sqlite3_column_int64(capacity_stmt, 0));
+        }
+        sqlite3_finalize(capacity_stmt);
+        capacity = external_bytes >= capacity ? 0 : capacity - external_bytes;
         if (item.payload.size() > capacity) {
             sqlite3_exec(db, "ROLLBACK", nullptr, nullptr, nullptr);
             return;
@@ -492,6 +556,18 @@ void llama_token_cache_note_tokenizer_hit(bool hit) {
     cache().note_tokenizer(hit);
 }
 
+std::string llama_token_cache_database_path() {
+    return cache().database_path();
+}
+
+uint64_t llama_token_cache_capacity() {
+    return cache().capacity();
+}
+
+void llama_token_cache_set_external_bytes(uint64_t bytes) {
+    cache().set_external_bytes(bytes);
+}
+
 llama_token_cache_params llama_token_cache_default_params() {
     return {nullptr, DEFAULT_CAPACITY};
 }
diff --git a/src/llama-token-cache.h b/src/llama-token-cache.h
index b922033..ad47cad 100644
--- a/src/llama-token-cache.h
+++ b/src/llama-token-cache.h
@@ -27,3 +27,8 @@ void llama_token_cache_store(
 
 void llama_token_cache_note_tokenizer_hit(bool hit);
 
+// Internal helpers used by tokenizer-longhaul artifacts.
+// Opening the cache here also fixes the configured path for the process.
+std::string llama_token_cache_database_path();
+uint64_t llama_token_cache_capacity();
+void llama_token_cache_set_external_bytes(uint64_t bytes);
diff --git a/src/llama-tokenizer-longhaul.cpp b/src/llama-tokenizer-longhaul.cpp
new file mode 100644
index 0000000..8738728
--- /dev/null
+++ b/src/llama-tokenizer-longhaul.cpp
@@ -0,0 +1,471 @@
+#include "llama-tokenizer-longhaul.h"
+
+#include "llama-token-cache.h"
+
+#include <sqlite3.h>
+
+#include <algorithm>
+#include <chrono>
+#include <filesystem>
+#include <list>
+#include <mutex>
+#include <thread>
+#include <unordered_map>
+
+#if defined(_WIN32)
+#  include <process.h>
+#else
+#  include <unistd.h>
+#endif
+
+namespace fs = std::filesystem;
+
+namespace {
+
+constexpr int INDEX_VERSION = 1;
+
+int process_id() {
+#if defined(_WIN32)
+    return _getpid();
+#else
+    return getpid();
+#endif
+}
+
+bool exec_sql(sqlite3 * db, const char * sql, std::string & error) {
+    char * message = nullptr;
+    if (sqlite3_exec(db, sql, nullptr, nullptr, &message) == SQLITE_OK) {
+        return true;
+    }
+    error = message ? message : sqlite3_errmsg(db);
+    sqlite3_free(message);
+    return false;
+}
+
+struct lock_directory {
+    fs::path path;
+    bool owned = false;
+
+    ~lock_directory() {
+        if (owned) {
+            std::error_code ec;
+            fs::remove(path, ec);
+        }
+    }
+};
+
+uint64_t tokenizer_artifact_bytes(const fs::path & directory) {
+    uint64_t total = 0;
+    std::error_code ec;
+    for (const auto & entry : fs::directory_iterator(directory, ec)) {
+        if (ec) break;
+        if (!entry.is_regular_file(ec) || entry.path().extension() != ".sqlite3") continue;
+        total += entry.file_size(ec);
+        if (ec) {
+            ec.clear();
+        }
+    }
+    return total;
+}
+
+} // namespace
+
+struct llama_tokenizer_longhaul_index::impl {
+    struct cache_entry {
+        int value;
+        uint64_t bytes;
+        std::list<std::string>::iterator position;
+    };
+
+    std::string source_key;
+    uint64_t capacity;
+    fs::path artifact;
+    sqlite3 * db = nullptr;
+    std::string id;
+    uint64_t merge_count = 0;
+
+    mutable std::mutex mutex;
+    mutable uint64_t used = 0;
+    mutable std::list<std::string> lru;
+    mutable std::unordered_map<std::string, cache_entry> values;
+
+    impl(std::string source_key, uint64_t capacity)
+        : source_key(std::move(source_key)), capacity(capacity) {
+    }
+
+    ~impl() {
+        if (db) {
+            sqlite3_close(db);
+        }
+    }
+
+    bool open_existing(std::string & error) {
+        if (!fs::exists(artifact)) {
+            return false;
+        }
+        sqlite3 * opened = nullptr;
+        if (sqlite3_open_v2(artifact.string().c_str(), &opened,
+                SQLITE_OPEN_READONLY | SQLITE_OPEN_FULLMUTEX, nullptr) != SQLITE_OK) {
+            error = opened ? sqlite3_errmsg(opened) : "failed to open tokenizer index";
+            if (opened) sqlite3_close(opened);
+            return false;
+        }
+
+        sqlite3_stmt * stmt = nullptr;
+        const char * sql =
+            "SELECT version, tokenizer_id, n_merges FROM metadata WHERE complete=1 LIMIT 1";
+        bool valid = sqlite3_prepare_v2(opened, sql, -1, &stmt, nullptr) == SQLITE_OK &&
+            sqlite3_step(stmt) == SQLITE_ROW &&
+            sqlite3_column_int(stmt, 0) == INDEX_VERSION;
+        if (valid) {
+            const unsigned char * value = sqlite3_column_text(stmt, 1);
+            id = value ? reinterpret_cast<const char *>(value) : "";
+            merge_count = static_cast<uint64_t>(sqlite3_column_int64(stmt, 2));
+            valid = !id.empty();
+        }
+        sqlite3_finalize(stmt);
+        if (!valid) {
+            error = "tokenizer index is incomplete or has an unsupported version";
+            sqlite3_close(opened);
+            return false;
+        }
+        db = opened;
+        sqlite3_busy_timeout(db, 5000);
+        return true;
+    }
+
+    bool build(
+            const std::vector<llama_tokenizer_longhaul_reverse> & reverse,
+            const std::vector<llama_tokenizer_longhaul_merge> & merges,
+            const std::string & tokenizer_id,
+            std::string & error) {
+        const fs::path temp = artifact.string() + ".tmp." + std::to_string(process_id());
+        std::error_code ec;
+        fs::remove(temp, ec);
+
+        sqlite3 * output = nullptr;
+        if (sqlite3_open_v2(temp.string().c_str(), &output,
+                SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_EXCLUSIVE, nullptr) != SQLITE_OK) {
+            error = output ? sqlite3_errmsg(output) : "failed to create tokenizer index";
+            if (output) sqlite3_close(output);
+            return false;
+        }
+        auto fail = [&](const std::string & message) {
+            error = message;
+            sqlite3_close(output);
+            output = nullptr;
+            std::error_code remove_ec;
+            fs::remove(temp, remove_ec);
+            return false;
+        };
+
+        if (!exec_sql(output,
+                "PRAGMA journal_mode=OFF;"
+                "PRAGMA synchronous=OFF;"
+                "PRAGMA locking_mode=EXCLUSIVE;"
+                "CREATE TABLE metadata("
+                " version INTEGER NOT NULL,complete INTEGER NOT NULL,tokenizer_id TEXT NOT NULL,"
+                " n_reverse INTEGER NOT NULL,n_merges INTEGER NOT NULL);"
+                "CREATE TABLE reverse_tokens(text BLOB PRIMARY KEY,id INTEGER NOT NULL) WITHOUT ROWID;"
+                "CREATE TABLE merges(left_text BLOB NOT NULL,right_text BLOB NOT NULL,rank INTEGER NOT NULL,"
+                " PRIMARY KEY(left_text,right_text)) WITHOUT ROWID;"
+                "BEGIN IMMEDIATE;", error)) {
+            return fail(error);
+        }
+
+        sqlite3_stmt * insert_reverse = nullptr;
+        sqlite3_stmt * insert_merge = nullptr;
+        if (sqlite3_prepare_v2(output,
+                "INSERT INTO reverse_tokens(text,id) VALUES(?1,?2)", -1, &insert_reverse, nullptr) != SQLITE_OK ||
+            sqlite3_prepare_v2(output,
+                "INSERT INTO merges(left_text,right_text,rank) VALUES(?1,?2,?3)",
+                -1, &insert_merge, nullptr) != SQLITE_OK) {
+            if (insert_reverse) sqlite3_finalize(insert_reverse);
+            if (insert_merge) sqlite3_finalize(insert_merge);
+            return fail(sqlite3_errmsg(output));
+        }
+
+        for (const auto & item : reverse) {
+            sqlite3_bind_blob(insert_reverse, 1, item.text.data(), int(item.text.size()), SQLITE_STATIC);
+            sqlite3_bind_int(insert_reverse, 2, item.id);
+            if (sqlite3_step(insert_reverse) != SQLITE_DONE) {
+                const std::string message = sqlite3_errmsg(output);
+                sqlite3_finalize(insert_reverse);
+                sqlite3_finalize(insert_merge);
+                return fail(message);
+            }
+            sqlite3_reset(insert_reverse);
+            sqlite3_clear_bindings(insert_reverse);
+        }
+        for (const auto & item : merges) {
+            sqlite3_bind_blob(insert_merge, 1, item.left.data(), int(item.left.size()), SQLITE_STATIC);
+            sqlite3_bind_blob(insert_merge, 2, item.right.data(), int(item.right.size()), SQLITE_STATIC);
+            sqlite3_bind_int(insert_merge, 3, item.rank);
+            if (sqlite3_step(insert_merge) != SQLITE_DONE) {
+                const std::string message = sqlite3_errmsg(output);
+                sqlite3_finalize(insert_reverse);
+                sqlite3_finalize(insert_merge);
+                return fail(message);
+            }
+            sqlite3_reset(insert_merge);
+            sqlite3_clear_bindings(insert_merge);
+        }
+        sqlite3_finalize(insert_reverse);
+        sqlite3_finalize(insert_merge);
+
+        sqlite3_stmt * metadata = nullptr;
+        if (sqlite3_prepare_v2(output,
+                "INSERT INTO metadata VALUES(?1,1,?2,?3,?4)", -1, &metadata, nullptr) != SQLITE_OK) {
+            return fail(sqlite3_errmsg(output));
+        }
+        sqlite3_bind_int(metadata, 1, INDEX_VERSION);
+        sqlite3_bind_text(metadata, 2, tokenizer_id.c_str(), -1, SQLITE_STATIC);
+        sqlite3_bind_int64(metadata, 3, static_cast<sqlite3_int64>(reverse.size()));
+        sqlite3_bind_int64(metadata, 4, static_cast<sqlite3_int64>(merges.size()));
+        const bool metadata_ok = sqlite3_step(metadata) == SQLITE_DONE;
+        sqlite3_finalize(metadata);
+        if (!metadata_ok || !exec_sql(output, "COMMIT;", error)) {
+            return fail(metadata_ok ? error : sqlite3_errmsg(output));
+        }
+        sqlite3_close(output);
+        output = nullptr;
+
+        const uint64_t persistent_capacity = llama_token_cache_capacity();
+        const uint64_t artifact_size = fs::file_size(temp, ec);
+        if (ec || artifact_size > persistent_capacity) {
+            fs::remove(temp, ec);
+            error = "completed tokenizer index does not fit in --token-cache-size";
+            return false;
+        }
+
+        struct artifact_candidate {
+            fs::path path;
+            fs::file_time_type modified;
+            uint64_t size;
+        };
+        std::vector<artifact_candidate> candidates;
+        uint64_t existing_bytes = 0;
+        for (const auto & entry : fs::directory_iterator(artifact.parent_path(), ec)) {
+            if (ec) break;
+            if (!entry.is_regular_file(ec) || entry.path().extension() != ".sqlite3" ||
+                    entry.path() == artifact || entry.path() == temp) {
+                continue;
+            }
+            const uint64_t size = entry.file_size(ec);
+            if (ec) {
+                ec.clear();
+                continue;
+            }
+            existing_bytes += size;
+            candidates.push_back({entry.path(), entry.last_write_time(ec), size});
+            if (ec) ec.clear();
+        }
+        std::sort(candidates.begin(), candidates.end(),
+            [](const artifact_candidate & a, const artifact_candidate & b) {
+                return a.modified < b.modified;
+            });
+        for (const auto & candidate : candidates) {
+            if (existing_bytes + artifact_size <= persistent_capacity) break;
+            fs::remove(candidate.path, ec);
+            if (!ec) existing_bytes -= std::min(existing_bytes, candidate.size);
+            ec.clear();
+        }
+        if (existing_bytes + artifact_size > persistent_capacity) {
+            fs::remove(temp, ec);
+            error = "tokenizer indexes do not fit in --token-cache-size";
+            return false;
+        }
+
+        fs::rename(temp, artifact, ec);
+        if (ec) {
+            const std::string rename_error = ec.message();
+            // A competing process may have published the same immutable artifact.
+            std::error_code remove_ec;
+            fs::remove(temp, remove_ec);
+            std::string ignored;
+            if (open_existing(ignored)) {
+                return true;
+            }
+            error = "failed to publish tokenizer index: " + rename_error;
+            return false;
+        }
+        const bool opened = open_existing(error);
+        if (opened) {
+            llama_token_cache_set_external_bytes(tokenizer_artifact_bytes(artifact.parent_path()));
+        }
+        return opened;
+    }
+
+    int lookup(const std::string & cache_key, const char * sql,
+            const std::string & first, const std::string * second, int missing) const {
+        std::lock_guard<std::mutex> lock(mutex);
+        auto found = values.find(cache_key);
+        if (found != values.end()) {
+            lru.splice(lru.begin(), lru, found->second.position);
+            return found->second.value;
+        }
+
+        sqlite3_stmt * stmt = nullptr;
+        int value = missing;
+        if (sqlite3_prepare_v2(db, sql, -1, &stmt, nullptr) == SQLITE_OK) {
+            sqlite3_bind_blob(stmt, 1, first.data(), int(first.size()), SQLITE_STATIC);
+            if (second) {
+                sqlite3_bind_blob(stmt, 2, second->data(), int(second->size()), SQLITE_STATIC);
+            }
+            if (sqlite3_step(stmt) == SQLITE_ROW) {
+                value = sqlite3_column_int(stmt, 0);
+            }
+        }
+        sqlite3_finalize(stmt);
+
+        const uint64_t bytes = cache_key.size() + sizeof(cache_entry) + sizeof(std::string);
+        if (bytes <= capacity) {
+            while (!lru.empty() && used + bytes > capacity) {
+                auto victim = values.find(lru.back());
+                if (victim != values.end()) {
+                    used -= victim->second.bytes;
+                    values.erase(victim);
+                }
+                lru.pop_back();
+            }
+            lru.push_front(cache_key);
+            values.emplace(cache_key, cache_entry{value, bytes, lru.begin()});
+            used += bytes;
+        }
+        return value;
+    }
+};
+
+llama_tokenizer_longhaul_index::llama_tokenizer_longhaul_index(
+        std::string source_key, uint64_t cache_bytes)
+    : pimpl(std::make_unique<impl>(std::move(source_key), cache_bytes)) {
+}
+
+llama_tokenizer_longhaul_index::~llama_tokenizer_longhaul_index() = default;
+
+bool llama_tokenizer_longhaul_index::prepare(
+        const std::vector<llama_tokenizer_longhaul_reverse> & reverse,
+        const std::vector<llama_tokenizer_longhaul_merge> & merges,
+        const std::string & tokenizer_id,
+        std::string & error) {
+    const std::string cache_db = llama_token_cache_database_path();
+    if (cache_db.empty()) {
+        error = "persistent token cache is disabled or unavailable";
+        return false;
+    }
+    const fs::path directory = fs::path(cache_db).parent_path() / "tokenizer-indexes";
+    std::error_code ec;
+    fs::create_directories(directory, ec);
+    if (ec) {
+        error = "failed to create tokenizer index directory: " + ec.message();
+        return false;
+    }
+    pimpl->artifact = directory / (llama_token_cache_hash(pimpl->source_key) + ".sqlite3");
+    if (pimpl->open_existing(error)) {
+        if (pimpl->id == tokenizer_id) {
+            llama_token_cache_set_external_bytes(tokenizer_artifact_bytes(directory));
+            return true;
+        }
+        sqlite3_close(pimpl->db);
+        pimpl->db = nullptr;
+        std::error_code stale_ec;
+        fs::remove(pimpl->artifact, stale_ec);
+    }
+
+    lock_directory lock{pimpl->artifact.string() + ".lock", false};
+    lock.owned = fs::create_directory(lock.path, ec);
+    if (!lock.owned) {
+        // Another process is building. Wait for its atomic publication.
+        for (int i = 0; i < 24000; ++i) {
+            std::this_thread::sleep_for(std::chrono::milliseconds(25));
+            std::string ignored;
+            if (pimpl->open_existing(ignored)) {
+                if (pimpl->id == tokenizer_id) {
+                    llama_token_cache_set_external_bytes(tokenizer_artifact_bytes(directory));
+                    return true;
+                }
+                sqlite3_close(pimpl->db);
+                pimpl->db = nullptr;
+            }
+            if (!fs::exists(lock.path)) {
+                lock.owned = fs::create_directory(lock.path, ec);
+                if (lock.owned) break;
+            }
+        }
+        if (!lock.owned) {
+            error = "timed out waiting for another tokenizer index builder";
+            return false;
+        }
+    }
+
+    error.clear();
+    if (pimpl->open_existing(error)) {
+        if (pimpl->id == tokenizer_id) {
+            llama_token_cache_set_external_bytes(tokenizer_artifact_bytes(directory));
+            return true;
+        }
+        sqlite3_close(pimpl->db);
+        pimpl->db = nullptr;
+    }
+    std::error_code remove_ec;
+    fs::remove(pimpl->artifact, remove_ec);
+    return pimpl->build(reverse, merges, tokenizer_id, error);
+}
+
+llama_token llama_tokenizer_longhaul_index::text_to_token(const std::string & text) const {
+    const std::string key = "t" + text;
+    return pimpl->lookup(key,
+        "SELECT id FROM reverse_tokens WHERE text=?1", text, nullptr, LLAMA_TOKEN_NULL);
+}
+
+int llama_tokenizer_longhaul_index::find_bpe_rank(
+        const std::string & left, const std::string & right) const {
+    std::string key;
+    key.reserve(left.size() + right.size() + 2);
+    key.push_back('m');
+    key += left;
+    key.push_back('\0');
+    key += right;
+    return pimpl->lookup(key,
+        "SELECT rank FROM merges WHERE left_text=?1 AND right_text=?2", left, &right, -1);
+}
+
+std::vector<std::string> llama_tokenizer_longhaul_index::get_bpe_merges() const {
+    std::lock_guard<std::mutex> lock(pimpl->mutex);
+    std::vector<std::string> result;
+    result.reserve(pimpl->merge_count);
+    sqlite3_stmt * stmt = nullptr;
+    if (sqlite3_prepare_v2(pimpl->db,
+            "SELECT left_text,right_text FROM merges ORDER BY rank", -1, &stmt, nullptr) != SQLITE_OK) {
+        return result;
+    }
+    while (sqlite3_step(stmt) == SQLITE_ROW) {
+        const char * left = static_cast<const char *>(sqlite3_column_blob(stmt, 0));
+        const int left_size = sqlite3_column_bytes(stmt, 0);
+        const char * right = static_cast<const char *>(sqlite3_column_blob(stmt, 1));
+        const int right_size = sqlite3_column_bytes(stmt, 1);
+        std::string item(left, left_size);
+        item.push_back(' ');
+        item.append(right, right_size);
+        result.push_back(std::move(item));
+    }
+    sqlite3_finalize(stmt);
+    return result;
+}
+
+uint64_t llama_tokenizer_longhaul_index::cache_bytes_used() const {
+    std::lock_guard<std::mutex> lock(pimpl->mutex);
+    return pimpl->used;
+}
+
+uint64_t llama_tokenizer_longhaul_index::cache_capacity() const {
+    return pimpl->capacity;
+}
+
+uint64_t llama_tokenizer_longhaul_index::n_merges() const {
+    return pimpl->merge_count;
+}
+
+const std::string & llama_tokenizer_longhaul_index::tokenizer_id() const {
+    return pimpl->id;
+}
diff --git a/src/llama-tokenizer-longhaul.h b/src/llama-tokenizer-longhaul.h
new file mode 100644
index 0000000..9d6072f
--- /dev/null
+++ b/src/llama-tokenizer-longhaul.h
@@ -0,0 +1,47 @@
+#pragma once
+
+#include "llama.h"
+
+#include <cstdint>
+#include <memory>
+#include <string>
+#include <vector>
+
+struct llama_tokenizer_longhaul_reverse {
+    std::string text;
+    llama_token id;
+};
+
+struct llama_tokenizer_longhaul_merge {
+    std::string left;
+    std::string right;
+    int rank;
+};
+
+class llama_tokenizer_longhaul_index {
+public:
+    llama_tokenizer_longhaul_index(std::string source_key, uint64_t cache_bytes);
+    ~llama_tokenizer_longhaul_index();
+
+    llama_tokenizer_longhaul_index(const llama_tokenizer_longhaul_index &) = delete;
+    llama_tokenizer_longhaul_index & operator=(const llama_tokenizer_longhaul_index &) = delete;
+
+    bool prepare(
+            const std::vector<llama_tokenizer_longhaul_reverse> & reverse,
+            const std::vector<llama_tokenizer_longhaul_merge> & merges,
+            const std::string & tokenizer_id,
+            std::string & error);
+
+    llama_token text_to_token(const std::string & text) const;
+    int find_bpe_rank(const std::string & left, const std::string & right) const;
+    std::vector<std::string> get_bpe_merges() const;
+
+    uint64_t cache_bytes_used() const;
+    uint64_t cache_capacity() const;
+    uint64_t n_merges() const;
+    const std::string & tokenizer_id() const;
+
+private:
+    struct impl;
+    std::unique_ptr<impl> pimpl;
+};
diff --git a/src/llama-vocab.cpp b/src/llama-vocab.cpp
index 72dd0e1..7d2f648 100644
--- a/src/llama-vocab.cpp
+++ b/src/llama-vocab.cpp
@@ -1,5 +1,6 @@
 #include "llama-vocab.h"
 #include "llama-token-cache.h"
+#include "llama-tokenizer-longhaul.h"
 
 #include "ggml.h"
 #include "gguf.h"
@@ -13,13 +14,16 @@
 #include <cctype>
 #include <cfloat>
 #include <cmath>
+#include <condition_variable>
 #include <cstdarg>
 #include <cstring>
 #include <forward_list>
 #include <limits>
 #include <map>
+#include <mutex>
 #include <queue>
 #include <set>
+#include <thread>
 #include <unordered_map>
 
 //
@@ -1846,12 +1850,37 @@ struct llama_vocab::impl {
 
     std::vector<char> precompiled_charsmap;
 
+    enum class longhaul_state {
+        disabled,
+        building,
+        ready,
+        failed,
+    };
+    bool tokenizer_longhaul = false;
+    uint64_t tokenizer_longhaul_cache_bytes = 0;
+    uint64_t tokenizer_longhaul_n_merges = 0;
+    mutable std::mutex tokenizer_longhaul_mutex;
+    mutable std::condition_variable tokenizer_longhaul_ready;
+    mutable longhaul_state tokenizer_longhaul_state = longhaul_state::disabled;
+    mutable std::string tokenizer_longhaul_error;
+    mutable std::unique_ptr<llama_tokenizer_longhaul_index> tokenizer_longhaul_index;
+    std::thread tokenizer_longhaul_worker;
+
     impl(const llama_vocab & vocab) : vocab(vocab) {
     }
 
-    ~impl() = default;
+    ~impl() {
+        if (tokenizer_longhaul_worker.joinable()) {
+            tokenizer_longhaul_worker.join();
+        }
+    }
 
-    void load(llama_model_loader & ml, const LLM_KV & kv);
+    void load(
+            llama_model_loader & ml,
+            const LLM_KV & kv,
+            bool tokenizer_longhaul,
+            uint64_t tokenizer_longhaul_cache_bytes);
+    void wait_for_tokenizer_longhaul() const;
 
     bool load_cache_snapshot(const std::vector<uint8_t> & snapshot);
     void reset_cache_snapshot_state();
@@ -1908,7 +1937,7 @@ struct llama_vocab::impl {
                          bool   special) const;
 
     // use cached data
-    const std::string & token_to_piece(llama_token token) const;
+    std::string token_to_piece(llama_token token) const;
 
     int32_t detokenize(
             const llama_token * tokens,
@@ -1928,11 +1957,29 @@ private:
     const llama_vocab & vocab;
 };
 
-void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
+void llama_vocab::impl::load(
+        llama_model_loader & ml,
+        const LLM_KV & kv,
+        bool tokenizer_longhaul_value,
+        uint64_t tokenizer_longhaul_cache_bytes_value) {
     struct gguf_context * ctx = ml.metadata;
 
+    tokenizer_longhaul = tokenizer_longhaul_value;
+    tokenizer_longhaul_cache_bytes = tokenizer_longhaul_cache_bytes_value;
+    if (tokenizer_longhaul) {
+        if (tokenizer_longhaul_cache_bytes == 0) {
+            throw std::runtime_error("tokenizer-longhaul cache budget must be positive");
+        }
+        if (ml.get_arch() != LLM_ARCH_QWEN35MOE && ml.get_arch() != LLM_ARCH_LAGUNA) {
+            throw std::runtime_error("tokenizer-longhaul currently requires a qwen35moe or laguna model");
+        }
+        if (ml.get_token_cache_source_key().empty()) {
+            throw std::runtime_error("tokenizer-longhaul requires a file-backed GGUF model");
+        }
+    }
+
     const std::string & source_cache_key = ml.get_token_cache_source_key();
-    if (!source_cache_key.empty()) {
+    if (!tokenizer_longhaul && !source_cache_key.empty()) {
         std::vector<uint8_t> snapshot;
         bool found = llama_token_cache_lookup(LLAMA_TOKEN_CACHE_KIND_TOKENIZER, source_cache_key, snapshot);
         if (found && snapshot.size() == 65 && snapshot[0] == 'A') {
@@ -1958,6 +2005,9 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
         ml.get_key(LLM_KV_TOKENIZER_TOKEN_TYPE_COUNT, n_token_types, false);
 
         if (tokenizer_model == "no_vocab" || tokenizer_model == "none") {
+            if (tokenizer_longhaul) {
+                throw std::runtime_error("tokenizer-longhaul requires a BPE tokenizer");
+            }
             type = LLAMA_VOCAB_TYPE_NONE;
 
             // default special tokens
@@ -3063,6 +3113,69 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
         }
     }
 
+    if (tokenizer_longhaul) {
+        if (type != LLAMA_VOCAB_TYPE_BPE ||
+                (tokenizer_pre != "qwen35" && tokenizer_pre != "laguna")) {
+            throw std::runtime_error(
+                "tokenizer-longhaul currently supports only qwen35 and laguna BPE tokenizers");
+        }
+
+        std::vector<llama_tokenizer_longhaul_reverse> reverse;
+        reverse.reserve(token_to_id.size());
+        while (!token_to_id.empty()) {
+            auto node = token_to_id.extract(token_to_id.begin());
+            reverse.push_back({std::move(node.key()), node.mapped()});
+        }
+        token_to_id.rehash(0);
+
+        std::vector<llama_tokenizer_longhaul_merge> merges;
+        merges.reserve(bpe_ranks.size());
+        while (!bpe_ranks.empty()) {
+            auto node = bpe_ranks.extract(bpe_ranks.begin());
+            auto key = std::move(node.key());
+            merges.push_back({std::move(key.first), std::move(key.second), node.mapped()});
+        }
+        bpe_ranks.rehash(0);
+        tokenizer_longhaul_n_merges = merges.size();
+        cache_token_to_piece.clear();
+        cache_token_to_piece.shrink_to_fit();
+
+        token_cache_id = llama_token_cache_hash(
+            std::string("tokenizer-longhaul-v1\n") + source_cache_key);
+        {
+            std::lock_guard<std::mutex> lock(tokenizer_longhaul_mutex);
+            tokenizer_longhaul_state = longhaul_state::building;
+        }
+        const uint64_t cache_bytes = tokenizer_longhaul_cache_bytes;
+        const std::string source_key = source_cache_key;
+        const std::string tokenizer_id = token_cache_id;
+        tokenizer_longhaul_worker = std::thread(
+            [this, source_key, cache_bytes, tokenizer_id,
+             reverse = std::move(reverse), merges = std::move(merges)]() mutable {
+                auto index = std::make_unique<llama_tokenizer_longhaul_index>(source_key, cache_bytes);
+                std::string error;
+                const bool ok = index->prepare(reverse, merges, tokenizer_id, error);
+                {
+                    std::lock_guard<std::mutex> lock(tokenizer_longhaul_mutex);
+                    if (ok) {
+                        tokenizer_longhaul_index = std::move(index);
+                        tokenizer_longhaul_state = longhaul_state::ready;
+                        LLAMA_LOG_INFO("%s: tokenizer-longhaul index is ready\n", "llama_vocab");
+                    } else {
+                        tokenizer_longhaul_error = error.empty()
+                            ? "unknown tokenizer-longhaul build error"
+                            : std::move(error);
+                        tokenizer_longhaul_state = longhaul_state::failed;
+                        LLAMA_LOG_ERROR("%s: tokenizer-longhaul index failed: %s\n",
+                            "llama_vocab", tokenizer_longhaul_error.c_str());
+                    }
+                }
+                tokenizer_longhaul_ready.notify_all();
+            });
+        LLAMA_LOG_INFO("%s: tokenizer-longhaul index is building in the background\n", __func__);
+        return;
+    }
+
     // Persist a versioned canonical snapshot of the effective tokenizer state.
     // The snapshot also serves as the namespace for text-to-token cache entries.
     {
@@ -3151,6 +3264,23 @@ void llama_vocab::impl::load(llama_model_loader & ml, const LLM_KV & kv) {
     }
 }
 
+void llama_vocab::impl::wait_for_tokenizer_longhaul() const {
+    if (!tokenizer_longhaul) {
+        return;
+    }
+    std::unique_lock<std::mutex> lock(tokenizer_longhaul_mutex);
+    if (tokenizer_longhaul_state == longhaul_state::disabled) {
+        return;
+    }
+    tokenizer_longhaul_ready.wait(lock, [this] {
+        return tokenizer_longhaul_state == longhaul_state::ready ||
+               tokenizer_longhaul_state == longhaul_state::failed;
+    });
+    if (tokenizer_longhaul_state == longhaul_state::failed) {
+        throw std::runtime_error("tokenizer-longhaul failed: " + tokenizer_longhaul_error);
+    }
+}
+
 void llama_vocab::impl::reset_cache_snapshot_state() {
     n_token_types = 0;
     tokenizer_model.clear();
@@ -3282,36 +3412,43 @@ std::string llama_vocab::impl::type_name() const{
 }
 
 bool llama_vocab::impl::is_normal(llama_token id) const {
+    wait_for_tokenizer_longhaul();
     GGML_ASSERT(type != LLAMA_VOCAB_TYPE_NONE);
     return id_to_token[id].attr & LLAMA_TOKEN_ATTR_NORMAL;
 }
 
 bool llama_vocab::impl::is_unknown(llama_token id) const {
+    wait_for_tokenizer_longhaul();
     GGML_ASSERT(type != LLAMA_VOCAB_TYPE_NONE);
     return id_to_token[id].attr & LLAMA_TOKEN_ATTR_UNKNOWN;
 }
 
 bool llama_vocab::impl::is_control(llama_token id) const {
+    wait_for_tokenizer_longhaul();
     GGML_ASSERT(type != LLAMA_VOCAB_TYPE_NONE);
     return id_to_token[id].attr & LLAMA_TOKEN_ATTR_CONTROL;
 }
 
 bool llama_vocab::impl::is_byte(llama_token id) const {
+    wait_for_tokenizer_longhaul();
     GGML_ASSERT(type != LLAMA_VOCAB_TYPE_NONE);
     return id_to_token[id].attr & LLAMA_TOKEN_ATTR_BYTE;
 }
 
 bool llama_vocab::impl::is_user_defined(llama_token id) const {
+    wait_for_tokenizer_longhaul();
     GGML_ASSERT(type != LLAMA_VOCAB_TYPE_NONE);
     return id_to_token[id].attr & LLAMA_TOKEN_ATTR_USER_DEFINED;
 }
 
 bool llama_vocab::impl::is_unused(llama_token id) const {
+    wait_for_tokenizer_longhaul();
     GGML_ASSERT(type != LLAMA_VOCAB_TYPE_NONE);
     return id_to_token[id].attr & LLAMA_TOKEN_ATTR_UNUSED;
 }
 
 bool llama_vocab::impl::is_eog(llama_token id) const {
+    wait_for_tokenizer_longhaul();
     return id != LLAMA_TOKEN_NULL && special_eog_ids.count(id) > 0;
 }
 
@@ -3339,6 +3476,7 @@ uint8_t llama_vocab::impl::token_to_byte(llama_token id) const {
 }
 
 llama_token_attr llama_vocab::impl::token_get_attr(llama_token id) const {
+    wait_for_tokenizer_longhaul();
     GGML_ASSERT(type != LLAMA_VOCAB_TYPE_NONE);
     return id_to_token.at(id).attr;
 }
@@ -3749,6 +3887,7 @@ std::vector<llama_token> llama_vocab::impl::tokenize(
         const std::string & raw_text,
         bool add_special,
         bool parse_special) const {
+    wait_for_tokenizer_longhaul();
     if (raw_text.empty() || token_cache_id.empty()) {
         return tokenize_uncached(raw_text, add_special, parse_special);
     }
@@ -3792,6 +3931,7 @@ std::vector<llama_token> llama_vocab::impl::tokenize(
 }
 
 int32_t llama_vocab::impl::token_to_piece(llama_token token, char * buf, int32_t length, int32_t lstrip, bool special) const {
+    wait_for_tokenizer_longhaul();
     // ref: https://github.com/ggml-org/llama.cpp/pull/7587#discussion_r1620983843
     static const int attr_special = LLAMA_TOKEN_ATTR_UNKNOWN | LLAMA_TOKEN_ATTR_CONTROL;
     const llama_token_attr attr = token_get_attr(token);
@@ -3908,7 +4048,11 @@ int32_t llama_vocab::impl::token_to_piece(llama_token token, char * buf, int32_t
     return 0;
 }
 
-const std::string & llama_vocab::impl::token_to_piece(llama_token token) const {
+std::string llama_vocab::impl::token_to_piece(llama_token token) const {
+    wait_for_tokenizer_longhaul();
+    if (tokenizer_longhaul) {
+        return token_to_piece_for_cache(token, true);
+    }
     return cache_token_to_piece.at(token);
 }
 
@@ -4027,7 +4171,15 @@ int32_t llama_vocab::impl::detokenize(
 void llama_vocab::impl::print_info() const {
     LLAMA_LOG_INFO("%s: vocab type            = %s\n",     __func__, type_name().c_str());
     LLAMA_LOG_INFO("%s: n_vocab               = %u\n",     __func__, vocab.n_tokens());
-    LLAMA_LOG_INFO("%s: n_merges              = %u\n",     __func__, (uint32_t) bpe_ranks.size());
+    LLAMA_LOG_INFO("%s: n_merges              = %u\n",     __func__,
+        (uint32_t) (tokenizer_longhaul ? tokenizer_longhaul_n_merges : bpe_ranks.size()));
+    if (tokenizer_longhaul) {
+        std::lock_guard<std::mutex> lock(tokenizer_longhaul_mutex);
+        LLAMA_LOG_INFO("%s: tokenizer longhaul     = %s, cache = %.2f MiB\n", __func__,
+            tokenizer_longhaul_state == longhaul_state::ready ? "ready" :
+            tokenizer_longhaul_state == longhaul_state::failed ? "failed" : "building",
+            tokenizer_longhaul_cache_bytes / 1024.0 / 1024.0);
+    }
 
     // special tokens
     if (special_bos_id  != LLAMA_TOKEN_NULL)    { LLAMA_LOG_INFO( "%s: BOS token             = %d '%s'\n", __func__, special_bos_id,     id_to_token.at(special_bos_id).text.c_str() );  }
@@ -4060,8 +4212,12 @@ llama_vocab::llama_vocab() : pimpl(new impl(*this)) {
 
 llama_vocab::~llama_vocab() = default;
 
-void llama_vocab::load(llama_model_loader & ml, const LLM_KV & kv) {
-    pimpl->load(ml, kv);
+void llama_vocab::load(
+        llama_model_loader & ml,
+        const LLM_KV & kv,
+        bool tokenizer_longhaul,
+        uint64_t tokenizer_longhaul_cache_bytes) {
+    pimpl->load(ml, kv, tokenizer_longhaul, tokenizer_longhaul_cache_bytes);
 }
 
 std::string llama_vocab::get_tokenizer_model() const {
@@ -4131,23 +4287,29 @@ llama_token llama_vocab::byte_to_token(uint8_t ch) const {
         case LLAMA_VOCAB_TYPE_SPM:
         case LLAMA_VOCAB_TYPE_UGM: {
             const char buf[7] = { '<', '0', 'x', hex[ch >> 4], hex[ch & 15], '>', 0 };
-            auto token = pimpl->token_to_id.find(buf);
-            if (token != pimpl->token_to_id.end()) {
-                return (*token).second;
+            const auto token = text_to_token(buf);
+            if (token != LLAMA_TOKEN_NULL) {
+                return token;
             }
             // Try to fall back to just the byte as a string
             const char buf2[2] = { (char)ch, 0 };
-            return pimpl->token_to_id.at(buf2);
+            const auto fallback = text_to_token(buf2);
+            if (fallback == LLAMA_TOKEN_NULL) throw std::out_of_range("byte token not found");
+            return fallback;
         }
         case LLAMA_VOCAB_TYPE_WPM:
         case LLAMA_VOCAB_TYPE_BPE: {
-            return pimpl->token_to_id.at(unicode_byte_to_utf8(ch));
+            const auto token = text_to_token(unicode_byte_to_utf8(ch));
+            if (token == LLAMA_TOKEN_NULL) throw std::out_of_range("byte token not found");
+            return token;
         }
         case LLAMA_VOCAB_TYPE_PLAMO2: {
             // PLaMo-2 uses byte tokens in format <0xXX>
             char hex_str[8];
             snprintf(hex_str, sizeof(hex_str), "<0x%02X>", ch);
-            return pimpl->token_to_id.at(hex_str);
+            const auto token = text_to_token(hex_str);
+            if (token == LLAMA_TOKEN_NULL) throw std::out_of_range("byte token not found");
+            return token;
         }
         default:
             GGML_ABORT("fatal error");
@@ -4156,6 +4318,10 @@ llama_token llama_vocab::byte_to_token(uint8_t ch) const {
 
 llama_token llama_vocab::text_to_token(const std::string & text) const {
     GGML_ASSERT(pimpl->type != LLAMA_VOCAB_TYPE_NONE);
+    pimpl->wait_for_tokenizer_longhaul();
+    if (pimpl->tokenizer_longhaul_index) {
+        return pimpl->tokenizer_longhaul_index->text_to_token(text);
+    }
     auto it = pimpl->token_to_id.find(text);
     if (it != pimpl->token_to_id.end()) {
         return (*it).second;
@@ -4165,16 +4331,19 @@ llama_token llama_vocab::text_to_token(const std::string & text) const {
 
 const llama_vocab::token_data & llama_vocab::get_token_data(llama_token id) const {
     GGML_ASSERT(pimpl->type != LLAMA_VOCAB_TYPE_NONE);
+    pimpl->wait_for_tokenizer_longhaul();
     return pimpl->id_to_token.at(id);
 }
 
 const char * llama_vocab::token_get_text(llama_token id) const {
     GGML_ASSERT(pimpl->type != LLAMA_VOCAB_TYPE_NONE);
+    pimpl->wait_for_tokenizer_longhaul();
     return pimpl->id_to_token.at(id).text.c_str();
 }
 
 float llama_vocab::token_get_score(llama_token id) const {
     GGML_ASSERT(pimpl->type != LLAMA_VOCAB_TYPE_NONE);
+    pimpl->wait_for_tokenizer_longhaul();
     return pimpl->id_to_token.at(id).score;
 }
 
@@ -4306,6 +4475,10 @@ int llama_vocab::find_bpe_rank(const std::string & token_left, const std::string
     GGML_ASSERT(token_left.find(' ')   == std::string::npos);
     GGML_ASSERT(token_right.find(' ')  == std::string::npos);
 
+    pimpl->wait_for_tokenizer_longhaul();
+    if (pimpl->tokenizer_longhaul_index) {
+        return pimpl->tokenizer_longhaul_index->find_bpe_rank(token_left, token_right);
+    }
     auto it = pimpl->bpe_ranks.find(std::make_pair(token_left, token_right));
     if (it == pimpl->bpe_ranks.end()) {
         return -1;
@@ -4315,6 +4488,10 @@ int llama_vocab::find_bpe_rank(const std::string & token_left, const std::string
 }
 
 std::vector<std::string> llama_vocab::get_bpe_merges() const {
+    pimpl->wait_for_tokenizer_longhaul();
+    if (pimpl->tokenizer_longhaul_index) {
+        return pimpl->tokenizer_longhaul_index->get_bpe_merges();
+    }
     int max_rank = -1;
     for (const auto & pair : pimpl->bpe_ranks) {
         max_rank = std::max(max_rank, pair.second);
@@ -4364,7 +4541,7 @@ std::vector<llama_token> llama_vocab::tokenize(
     return pimpl->tokenize(raw_text, add_special, parse_special);
 }
 
-const std::string & llama_vocab::token_to_piece(llama_token token) const {
+std::string llama_vocab::token_to_piece(llama_token token) const {
     return pimpl->token_to_piece(token);
 }
 
diff --git a/src/llama-vocab.h b/src/llama-vocab.h
index b7c2892..4719004 100644
--- a/src/llama-vocab.h
+++ b/src/llama-vocab.h
@@ -86,7 +86,11 @@ struct llama_vocab {
     llama_vocab();
     ~llama_vocab();
 
-    void load(llama_model_loader & ml, const LLM_KV & kv);
+    void load(
+            llama_model_loader & ml,
+            const LLM_KV & kv,
+            bool tokenizer_longhaul = false,
+            uint64_t tokenizer_longhaul_cache_bytes = 0);
 
     std::string get_tokenizer_model() const;
     std::string get_tokenizer_pre() const;
@@ -181,7 +185,7 @@ struct llama_vocab {
                          bool   special) const;
 
     // use cached data
-    const std::string & token_to_piece(llama_token token) const;
+    std::string token_to_piece(llama_token token) const;
 
     int32_t detokenize(
             const llama_token * tokens,
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 5520b83..3a714a5 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -259,6 +259,8 @@ set_tests_properties(test-thread-safety PROPERTIES FIXTURES_REQUIRED test-downlo
 
 llama_build_and_test(test-arg-parser.cpp)
 llama_build_and_test(test-longhaul.cpp)
+llama_build_and_test(test-tokenizer-longhaul.cpp
+    ARGS ${PROJECT_SOURCE_DIR}/models/ggml-vocab-qwen35.gguf)
 llama_build_and_test(test-token-cache.cpp)
 target_include_directories(test-token-cache PRIVATE ${PROJECT_SOURCE_DIR}/src)
 
diff --git a/tests/test-arg-parser.cpp b/tests/test-arg-parser.cpp
index b278341..f0a7ae7 100644
--- a/tests/test-arg-parser.cpp
+++ b/tests/test-arg-parser.cpp
@@ -160,6 +160,21 @@ static void test(void) {
     assert(params.load_mode == LLAMA_LOAD_MODE_LONGHAUL);
     assert(params.longhaul_cache_bytes == 2ULL * 1024 * 1024 * 1024);
 
+    params.tokenizer_longhaul = false;
+    params.tokenizer_longhaul_cache_bytes = 0;
+    argv = {"binary_name", "--tokenizer-longhaul"};
+    assert(false == common_params_parse(argv.size(), list_str_to_char(argv).data(), params, LLAMA_EXAMPLE_COMMON));
+
+    argv = {"binary_name", "--tokenizer-longhaul", "--tokenizer-longhaul-cache", "64"};
+    assert(true == common_params_parse(argv.size(), list_str_to_char(argv).data(), params, LLAMA_EXAMPLE_COMMON));
+    assert(params.tokenizer_longhaul);
+    assert(params.tokenizer_longhaul_cache_bytes == 64ULL * 1024 * 1024);
+
+    params.tokenizer_longhaul = false;
+    params.tokenizer_longhaul_cache_bytes = 0;
+    argv = {"binary_name", "--tokenizer-longhaul-cache", "64"};
+    assert(false == common_params_parse(argv.size(), list_str_to_char(argv).data(), params, LLAMA_EXAMPLE_COMMON));
+
     argv = {"binary_name", "--token-cache-size", "256", "--token-cache-dir", "/tmp/llama-token-cache-test.sqlite3"};
     assert(true == common_params_parse(argv.size(), list_str_to_char(argv).data(), params, LLAMA_EXAMPLE_COMMON));
     assert(params.token_cache_size_mib == 256);
diff --git a/tests/test-tokenizer-longhaul.cpp b/tests/test-tokenizer-longhaul.cpp
new file mode 100644
index 0000000..7c74ceb
--- /dev/null
+++ b/tests/test-tokenizer-longhaul.cpp
@@ -0,0 +1,144 @@
+#include "llama.h"
+#include "../src/llama-token-cache.h"
+#include "../src/llama-tokenizer-longhaul.h"
+
+#include <chrono>
+#include <cstring>
+#include <filesystem>
+#include <string>
+#include <thread>
+#include <vector>
+
+#undef NDEBUG
+#include <cassert>
+
+static std::vector<llama_token> tokenize(const llama_vocab * vocab, const std::string & text) {
+    int32_t count = llama_tokenize(vocab, text.data(), int32_t(text.size()), nullptr, 0, false, true);
+    assert(count < 0);
+    std::vector<llama_token> result(size_t(-count));
+    count = llama_tokenize(vocab, text.data(), int32_t(text.size()), result.data(), result.size(), false, true);
+    assert(count == int32_t(result.size()));
+    return result;
+}
+
+int main(int argc, char ** argv) {
+    namespace fs = std::filesystem;
+
+    const fs::path root = fs::temp_directory_path() /
+        ("llama-tokenizer-longhaul-test-" + std::to_string(
+            std::chrono::high_resolution_clock::now().time_since_epoch().count()));
+    const std::string db = (root / "token-cache.sqlite3").string();
+    const llama_token_cache_params params = {
+        db.c_str(),
+        128 * 1024 * 1024,
+    };
+    assert(llama_token_cache_configure(params));
+    assert(llama_token_cache_clear());
+
+    std::vector<llama_tokenizer_longhaul_reverse> reverse;
+    std::vector<llama_tokenizer_longhaul_merge> merges;
+    for (int i = 0; i < 200; ++i) {
+        reverse.push_back({"token-" + std::to_string(i), i});
+        if (i > 0) {
+            merges.push_back({
+                "token-" + std::to_string(i - 1),
+                "token-" + std::to_string(i),
+                i - 1,
+            });
+        }
+    }
+
+    {
+        llama_tokenizer_longhaul_index index("source:test", 512);
+        std::string error;
+        assert(index.prepare(reverse, merges, "tokenizer-id", error));
+        assert(error.empty());
+        assert(index.n_merges() == merges.size());
+
+        for (int i = 0; i < 200; ++i) {
+            assert(index.text_to_token("token-" + std::to_string(i)) == i);
+        }
+        assert(index.text_to_token("missing") == LLAMA_TOKEN_NULL);
+        for (int i = 1; i < 200; ++i) {
+            assert(index.find_bpe_rank(
+                "token-" + std::to_string(i - 1),
+                "token-" + std::to_string(i)) == i - 1);
+        }
+        assert(index.find_bpe_rank("missing", "pair") == -1);
+        assert(index.cache_bytes_used() <= index.cache_capacity());
+
+        const auto loaded_merges = index.get_bpe_merges();
+        assert(loaded_merges.size() == merges.size());
+        assert(loaded_merges.front() == "token-0 token-1");
+        assert(loaded_merges.back() == "token-198 token-199");
+    }
+
+    // A warm open must use the completed artifact even without rebuild inputs.
+    {
+        llama_tokenizer_longhaul_index index("source:test", 128);
+        std::string error;
+        assert(index.prepare({}, {}, "tokenizer-id", error));
+        assert(index.text_to_token("token-42") == 42);
+
+        std::vector<std::thread> workers;
+        for (int thread = 0; thread < 4; ++thread) {
+            workers.emplace_back([&index, thread] {
+                for (int i = thread; i < 200; i += 4) {
+                    assert(index.text_to_token("token-" + std::to_string(i)) == i);
+                }
+            });
+        }
+        for (auto & worker : workers) worker.join();
+        assert(index.cache_bytes_used() <= index.cache_capacity());
+    }
+
+    if (argc > 1) {
+        llama_backend_init();
+
+        llama_model_params normal_params = llama_model_default_params();
+        normal_params.vocab_only = true;
+        llama_model * normal = llama_model_load_from_file(argv[1], normal_params);
+        assert(normal != nullptr);
+
+        llama_model_kv_override overrides[2] = {};
+        std::strcpy(overrides[0].key, "general.architecture");
+        overrides[0].tag = LLAMA_KV_OVERRIDE_TYPE_STR;
+        std::strcpy(overrides[0].val_str, "qwen35moe");
+
+        llama_model_params longhaul_params = llama_model_default_params();
+        longhaul_params.vocab_only = true;
+        longhaul_params.kv_overrides = overrides;
+        longhaul_params.tokenizer_longhaul = true;
+        longhaul_params.tokenizer_longhaul_cache_bytes = 1024;
+        llama_model * longhaul = llama_model_load_from_file(argv[1], longhaul_params);
+        assert(longhaul != nullptr);
+
+        const llama_vocab * normal_vocab = llama_model_get_vocab(normal);
+        const llama_vocab * longhaul_vocab = llama_model_get_vocab(longhaul);
+        for (const std::string & text : {
+                "Hello, world!",
+                " tokenizer longhaul",
+                "Qwen3.5: 12345\n",
+                "<|im_end|>",
+                "Unicode: Καλημέρα 世界 🚚",
+            }) {
+            const auto expected = tokenize(normal_vocab, text);
+            const auto actual = tokenize(longhaul_vocab, text);
+            assert(actual == expected);
+            for (const auto token : actual) {
+                assert(std::strcmp(
+                    llama_vocab_get_text(normal_vocab, token),
+                    llama_vocab_get_text(longhaul_vocab, token)) == 0);
+            }
+        }
+
+        llama_model_free(longhaul);
+        llama_model_free(normal);
+        llama_backend_free();
+    }
+
+    assert(llama_token_cache_clear());
+    std::error_code ec;
+    fs::remove_all(root, ec);
+    return 0;
+}
diff --git a/tools/cli/README.md b/tools/cli/README.md
index ac147a0..64aeac6 100644
--- a/tools/cli/README.md
+++ b/tools/cli/README.md
@@ -35,6 +35,8 @@
 | `--token-cache-size N` | shared tokenizer and tokenized-text cache size in MiB (default: 5120, 0 = disable)<br/>(env: LLAMA_ARG_TOKEN_CACHE_SIZE) |
 | `--token-cache-dir PATH` | path to the shared tokenizer and tokenized-text cache database<br/>(env: LLAMA_ARG_TOKEN_CACHE_DIR) |
 | `--token-cache-clear` | clear the shared tokenizer and tokenized-text cache before loading the model<br/>(env: LLAMA_ARG_TOKEN_CACHE_CLEAR) |
+| `--tokenizer-longhaul` | build and page the Qwen3.5/Laguna tokenizer through a bounded cache<br/>(env: LLAMA_ARG_TOKENIZER_LONGHAUL) |
+| `--tokenizer-longhaul-cache N` | tokenizer-longhaul RAM cache size in MiB<br/>(env: LLAMA_ARG_TOKENIZER_LONGHAUL_CACHE) |
 | `-fa, --flash-attn [on\|off\|auto]` | set Flash Attention use ('on', 'off', or 'auto', default: 'auto')<br/>(env: LLAMA_ARG_FLASH_ATTN) |
 | `-p, --prompt PROMPT` | prompt to start generation with; for system message, use -sys |
 | `--perf, --no-perf` | whether to enable internal libllama performance timings (default: false)<br/>(env: LLAMA_ARG_PERF) |
diff --git a/tools/completion/README.md b/tools/completion/README.md
index d2b2df3..cf1a099 100644
--- a/tools/completion/README.md
+++ b/tools/completion/README.md
@@ -118,6 +118,8 @@ llama-completion.exe -m models\gemma-1.1-7b-it.Q4_K_M.gguf --ignore-eos -n -1
 | `--token-cache-size N` | shared tokenizer and tokenized-text cache size in MiB (default: 5120, 0 = disable)<br/>(env: LLAMA_ARG_TOKEN_CACHE_SIZE) |
 | `--token-cache-dir PATH` | path to the shared tokenizer and tokenized-text cache database<br/>(env: LLAMA_ARG_TOKEN_CACHE_DIR) |
 | `--token-cache-clear` | clear the shared tokenizer and tokenized-text cache before loading the model<br/>(env: LLAMA_ARG_TOKEN_CACHE_CLEAR) |
+| `--tokenizer-longhaul` | build and page the Qwen3.5/Laguna tokenizer through a bounded cache<br/>(env: LLAMA_ARG_TOKENIZER_LONGHAUL) |
+| `--tokenizer-longhaul-cache N` | tokenizer-longhaul RAM cache size in MiB<br/>(env: LLAMA_ARG_TOKENIZER_LONGHAUL_CACHE) |
 | `-fa, --flash-attn [on\|off\|auto]` | set Flash Attention use ('on', 'off', or 'auto', default: 'auto')<br/>(env: LLAMA_ARG_FLASH_ATTN) |
 | `-p, --prompt PROMPT` | prompt to start generation with; for system message, use -sys |
 | `--perf, --no-perf` | whether to enable internal libllama performance timings (default: false)<br/>(env: LLAMA_ARG_PERF) |
diff --git a/tools/llama-bench/README.md b/tools/llama-bench/README.md
index 91c3711..98a93be 100644
--- a/tools/llama-bench/README.md
+++ b/tools/llama-bench/README.md
@@ -57,6 +57,8 @@ test parameters:
   -ctk, --cache-type-k <t>                  (default: f16)
   -ctv, --cache-type-v <t>                  (default: f16)
   --longhaul-cache <GiB>                    expert cache size for longhaul mode
+  --tokenizer-longhaul                      page tokenizer indexes through a bounded cache
+  --tokenizer-longhaul-cache <MiB>          tokenizer lookup cache size
   -t, --threads <n>                         (default: system dependent)
   -C, --cpu-mask <hex,hex>                  (default: 0x0)
   --cpu-strict <0|1>                        (default: 0)
diff --git a/tools/llama-bench/llama-bench.cpp b/tools/llama-bench/llama-bench.cpp
index f148704..74523c4 100644
--- a/tools/llama-bench/llama-bench.cpp
+++ b/tools/llama-bench/llama-bench.cpp
@@ -342,6 +342,8 @@ struct cmd_params {
     std::vector<llama_split_mode>    split_mode;
     std::vector<llama_load_mode>     load_mode;
     uint64_t                         longhaul_cache_bytes;
+    bool                             tokenizer_longhaul;
+    uint64_t                         tokenizer_longhaul_cache_bytes;
     std::vector<int>                 main_gpu;
     std::vector<bool>                no_kv_offload;
     std::vector<llama_flash_attn_type> flash_attn;
@@ -387,6 +389,8 @@ static const cmd_params cmd_params_defaults = {
     /* split_mode           */ { LLAMA_SPLIT_MODE_LAYER },
     /* load_mode            */ { LLAMA_LOAD_MODE_MMAP },
     /* longhaul_cache_bytes */ 0,
+    /* tokenizer_longhaul   */ false,
+    /* tokenizer_longhaul_cache_bytes */ 0,
     /* main_gpu             */ { 0 },
     /* no_kv_offload        */ { false },
     /* flash_attn           */ { LLAMA_FLASH_ATTN_TYPE_AUTO },
@@ -463,6 +467,8 @@ static void print_usage(int /* argc */, char ** argv) {
     printf("  -dev, --device <dev0/dev1/...>                    (default: auto)\n");
     printf("  -lm, --load-mode <none|mmap|mlock|mmap+mlock|dio|longhaul> (default: %s)\n", join(transform_to_str(cmd_params_defaults.load_mode, llama_load_mode_name), ",").c_str());
     printf("  --longhaul-cache <GiB>                           expert cache size for longhaul mode\n");
+    printf("  --tokenizer-longhaul                             page tokenizer indexes through a bounded cache\n");
+    printf("  --tokenizer-longhaul-cache <MiB>                 tokenizer lookup cache size (required with --tokenizer-longhaul)\n");
     printf("  -mmp, --mmap <0|1>                                (DEPRECATED IN FAVOUR OF --load-mode)\n");
     printf("  -dio, --direct-io <0|1>                           (DEPRECATED IN FAVOUR OF --load-mode)\n");
     printf("  -embd, --embeddings <0|1>                         (default: %s)\n", join(cmd_params_defaults.embeddings, ",").c_str());
@@ -525,6 +531,8 @@ static cmd_params parse_cmd_params(int argc, char ** argv) {
     params.no_warmup            = cmd_params_defaults.no_warmup;
     params.offline              = cmd_params_defaults.offline;
     params.longhaul_cache_bytes = cmd_params_defaults.longhaul_cache_bytes;
+    params.tokenizer_longhaul = cmd_params_defaults.tokenizer_longhaul;
+    params.tokenizer_longhaul_cache_bytes = cmd_params_defaults.tokenizer_longhaul_cache_bytes;
 
     if (const char * env = getenv("HF_TOKEN")) {
         params.hf_token = env;
@@ -801,6 +809,19 @@ static cmd_params parse_cmd_params(int argc, char ** argv) {
                     break;
                 }
                 params.longhaul_cache_bytes = gib * 1024 * 1024 * 1024;
+            } else if (arg == "--tokenizer-longhaul") {
+                params.tokenizer_longhaul = true;
+            } else if (arg == "--tokenizer-longhaul-cache") {
+                if (++i >= argc) {
+                    invalid_param = true;
+                    break;
+                }
+                const uint64_t mib = std::stoull(argv[i]);
+                if (mib == 0 || mib > UINT64_MAX / 1024 / 1024) {
+                    invalid_param = true;
+                    break;
+                }
+                params.tokenizer_longhaul_cache_bytes = mib * 1024 * 1024;
             } else if (arg == "-mg" || arg == "--main-gpu") {
                 if (++i >= argc) {
                     invalid_param = true;
@@ -1157,6 +1178,10 @@ static cmd_params parse_cmd_params(int argc, char ** argv) {
         fprintf(stderr, "error: longhaul load mode requires --longhaul-cache N\n");
         exit(1);
     }
+    if (params.tokenizer_longhaul != (params.tokenizer_longhaul_cache_bytes != 0)) {
+        fprintf(stderr, "error: --tokenizer-longhaul and --tokenizer-longhaul-cache must be used together\n");
+        exit(1);
+    }
     if (params.main_gpu.empty()) {
         params.main_gpu = cmd_params_defaults.main_gpu;
     }
@@ -1224,6 +1249,8 @@ struct cmd_params_instance {
     llama_split_mode   split_mode;
     llama_load_mode    load_mode;
     uint64_t           longhaul_cache_bytes;
+    bool               tokenizer_longhaul;
+    uint64_t           tokenizer_longhaul_cache_bytes;
     int                main_gpu;
     bool               no_kv_offload;
     llama_flash_attn_type flash_attn;
@@ -1246,6 +1273,8 @@ struct cmd_params_instance {
         mparams.split_mode    = split_mode;
         mparams.load_mode     = load_mode;
         mparams.longhaul_cache_bytes = longhaul_cache_bytes;
+        mparams.tokenizer_longhaul = tokenizer_longhaul;
+        mparams.tokenizer_longhaul_cache_bytes = tokenizer_longhaul_cache_bytes;
         mparams.main_gpu      = main_gpu;
         mparams.tensor_split  = tensor_split.data();
         mparams.no_host       = no_host;
@@ -1294,6 +1323,8 @@ struct cmd_params_instance {
                split_mode == other.split_mode &&
                main_gpu == other.main_gpu && tensor_split == other.tensor_split &&
                load_mode == other.load_mode && longhaul_cache_bytes == other.longhaul_cache_bytes &&
+               tokenizer_longhaul == other.tokenizer_longhaul &&
+               tokenizer_longhaul_cache_bytes == other.tokenizer_longhaul_cache_bytes &&
                devices == other.devices && no_host == other.no_host &&
                vec_tensor_buft_override_equal(tensor_buft_overrides, other.tensor_buft_overrides);
     }
@@ -1368,6 +1399,8 @@ static std::vector<cmd_params_instance> get_cmd_params_instances(const cmd_param
                 /* .split_mode            = */ sm,
                 /* .load_mode             = */ lm,
                 /* .longhaul_cache_bytes  = */ params.longhaul_cache_bytes,
+                /* .tokenizer_longhaul    = */ params.tokenizer_longhaul,
+                /* .tokenizer_longhaul_cache_bytes = */ params.tokenizer_longhaul_cache_bytes,
                 /* .main_gpu              = */ mg,
                 /* .no_kv_offload         = */ nkvo,
                 /* .flash_attn            = */ fa,
@@ -1405,6 +1438,8 @@ static std::vector<cmd_params_instance> get_cmd_params_instances(const cmd_param
                 /* .split_mode            = */ sm,
                 /* .load_mode             = */ lm,
                 /* .longhaul_cache_bytes  = */ params.longhaul_cache_bytes,
+                /* .tokenizer_longhaul    = */ params.tokenizer_longhaul,
+                /* .tokenizer_longhaul_cache_bytes = */ params.tokenizer_longhaul_cache_bytes,
                 /* .main_gpu              = */ mg,
                 /* .no_kv_offload         = */ nkvo,
                 /* .flash_attn            = */ fa,
@@ -1442,6 +1477,8 @@ static std::vector<cmd_params_instance> get_cmd_params_instances(const cmd_param
                 /* .split_mode            = */ sm,
                 /* .load_mode             = */ lm,
                 /* .longhaul_cache_bytes  = */ params.longhaul_cache_bytes,
+                /* .tokenizer_longhaul    = */ params.tokenizer_longhaul,
+                /* .tokenizer_longhaul_cache_bytes = */ params.tokenizer_longhaul_cache_bytes,
                 /* .main_gpu              = */ mg,
                 /* .no_kv_offload         = */ nkvo,
                 /* .flash_attn            = */ fa,
@@ -1484,6 +1521,8 @@ struct test {
     llama_split_mode         split_mode;
     llama_load_mode          load_mode;
     uint64_t                 longhaul_cache_bytes;
+    bool                     tokenizer_longhaul;
+    uint64_t                 tokenizer_longhaul_cache_bytes;
     int                      main_gpu;
     bool                     no_kv_offload;
     llama_flash_attn_type    flash_attn;
@@ -1524,6 +1563,8 @@ struct test {
         split_mode     = inst.split_mode;
         load_mode      = inst.load_mode;
         longhaul_cache_bytes = inst.longhaul_cache_bytes;
+        tokenizer_longhaul = inst.tokenizer_longhaul;
+        tokenizer_longhaul_cache_bytes = inst.tokenizer_longhaul_cache_bytes;
         main_gpu       = inst.main_gpu;
         no_kv_offload  = inst.no_kv_offload;
         flash_attn     = inst.flash_attn;
@@ -1591,7 +1632,8 @@ struct test {
             "n_ubatch",       "n_threads",      "cpu_mask",      "cpu_strict",     "poll",
             "type_k",         "type_v",         "n_gpu_layers",  "n_cpu_moe",      "split_mode",
             "main_gpu",       "no_kv_offload",  "flash_attn",    "devices",        "tensor_split",
-            "tensor_buft_overrides",            "load_mode",     "longhaul_cache_bytes", "embeddings",
+            "tensor_buft_overrides",            "load_mode",     "longhaul_cache_bytes",
+            "tokenizer_longhaul", "tokenizer_longhaul_cache_bytes", "embeddings",
             "no_op_offload",  "no_host",        "fit_target",    "fit_min_ctx",
             "n_prompt",       "n_gen",          "n_depth",
             "test_time",      "avg_ns",         "stddev_ns",     "avg_ts",         "stddev_ts"
@@ -1607,11 +1649,11 @@ struct test {
             field == "main_gpu" || field == "n_prompt" || field == "n_gen" || field == "n_depth" || field == "avg_ns" ||
             field == "stddev_ns" || field == "no_op_offload" || field == "n_cpu_moe" ||
             field == "fit_target" || field == "fit_min_ctx" || field == "flash_attn" ||
-            field == "longhaul_cache_bytes") {
+            field == "longhaul_cache_bytes" || field == "tokenizer_longhaul_cache_bytes") {
             return INT;
         }
         if (field == "f16_kv" || field == "no_kv_offload" || field == "cpu_strict" ||
-            field == "embeddings" || field == "no_host") {
+            field == "embeddings" || field == "no_host" || field == "tokenizer_longhaul") {
             return BOOL;
         }
         if (field == "avg_ts" || field == "stddev_ts") {
@@ -1688,6 +1730,8 @@ struct test {
                                             tensor_buft_overrides_str,
                                             llama_load_mode_name(load_mode),
                                             std::to_string(longhaul_cache_bytes),
+                                            std::to_string(tokenizer_longhaul),
+                                            std::to_string(tokenizer_longhaul_cache_bytes),
                                             std::to_string(embeddings),
                                             std::to_string(no_op_offload),
                                             std::to_string(no_host),
@@ -2005,6 +2049,12 @@ struct markdown_printer : public printer {
         if (params.longhaul_cache_bytes != cmd_params_defaults.longhaul_cache_bytes) {
             fields.emplace_back("longhaul_cache_bytes");
         }
+        if (params.tokenizer_longhaul != cmd_params_defaults.tokenizer_longhaul) {
+            fields.emplace_back("tokenizer_longhaul");
+        }
+        if (params.tokenizer_longhaul_cache_bytes != cmd_params_defaults.tokenizer_longhaul_cache_bytes) {
+            fields.emplace_back("tokenizer_longhaul_cache_bytes");
+        }
         if (params.embeddings.size() > 1 || params.embeddings != cmd_params_defaults.embeddings) {
             fields.emplace_back("embeddings");
         }
diff --git a/tools/server/README.md b/tools/server/README.md
index 2df8893..41db8d6 100644
--- a/tools/server/README.md
+++ b/tools/server/README.md
@@ -56,6 +56,8 @@ For the full list of features, please refer to [server's changelog](https://gith
 | `--token-cache-size N` | shared tokenizer and tokenized-text cache size in MiB (default: 5120, 0 = disable)<br/>(env: LLAMA_ARG_TOKEN_CACHE_SIZE) |
 | `--token-cache-dir PATH` | path to the shared tokenizer and tokenized-text cache database<br/>(env: LLAMA_ARG_TOKEN_CACHE_DIR) |
 | `--token-cache-clear` | clear the shared tokenizer and tokenized-text cache before loading the model<br/>(env: LLAMA_ARG_TOKEN_CACHE_CLEAR) |
+| `--tokenizer-longhaul` | build and page the Qwen3.5/Laguna tokenizer through a bounded cache<br/>(env: LLAMA_ARG_TOKENIZER_LONGHAUL) |
+| `--tokenizer-longhaul-cache N` | tokenizer-longhaul RAM cache size in MiB<br/>(env: LLAMA_ARG_TOKENIZER_LONGHAUL_CACHE) |
 | `-fa, --flash-attn [on\|off\|auto]` | set Flash Attention use ('on', 'off', or 'auto', default: 'auto')<br/>(env: LLAMA_ARG_FLASH_ATTN) |
 | `--perf, --no-perf` | whether to enable internal libllama performance timings (default: false)<br/>(env: LLAMA_ARG_PERF) |
 | `-e, --escape, --no-escape` | whether to process escapes sequences (\n, \r, \t, \', \", \\) (default: true) |