diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c
index e8a375116..3c69a1ae0 100644
--- a/lib/compress/zstd_compress.c
+++ b/lib/compress/zstd_compress.c
@@ -2603,7 +2603,6 @@ static size_t ZSTD_compress_insertDictionary(ZSTD_CCtx* zc, const void* dict, si
     }
 }
 
-
 /*! ZSTD_compressBegin_internal() :
 *   @return : 0, or an error code */
 static size_t ZSTD_compressBegin_internal(ZSTD_CCtx* cctx,
@@ -2825,7 +2824,7 @@ static ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict* cdict) {
     return ZSTD_getParamsFromCCtx(cdict->refContext);
 }
 
-size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict, U64 pledgedSrcSize)
+size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize)
 {
     if (cdict->dictContentSize) CHECK_F(ZSTD_copyCCtx(cctx, cdict->refContext, pledgedSrcSize))
     else CHECK_F(ZSTD_compressBegin_advanced(cctx, NULL, 0, cdict->refContext->params, pledgedSrcSize));
diff --git a/lib/compress/zstdmt_compress.c b/lib/compress/zstdmt_compress.c
index 4e09a2082..283f76841 100644
--- a/lib/compress/zstdmt_compress.c
+++ b/lib/compress/zstdmt_compress.c
@@ -217,6 +217,7 @@ typedef struct {
     pthread_mutex_t* jobCompleted_mutex;
     pthread_cond_t* jobCompleted_cond;
     ZSTD_parameters params;
+    ZSTD_CDict* cdict;
     const void* dict;
     size_t dictSize;
     unsigned long long fullFrameSize;
@@ -227,8 +228,13 @@ void ZSTDMT_compressChunk(void* jobDescription)
 {
     ZSTDMT_jobDescription* const job = (ZSTDMT_jobDescription*)jobDescription;
     buffer_t const dstBuff = job->dstBuff;
-    size_t const initError = ZSTD_compressBegin_advanced(job->cctx, job->dict, job->dictSize, job->params, job->fullFrameSize);
-    if (ZSTD_isError(initError)) { job->cSize = initError; goto _endJob; }
+    if (job->cdict) {
+        size_t const initError = ZSTD_compressBegin_usingCDict(job->cctx, job->cdict, job->fullFrameSize);
+        if (ZSTD_isError(initError)) { job->cSize = initError; goto _endJob; }
+    } else {
+        size_t const initError = ZSTD_compressBegin_advanced(job->cctx, job->dict, job->dictSize, job->params, job->fullFrameSize);
+        if (ZSTD_isError(initError)) { job->cSize = initError; goto _endJob; }
+    }
     if (!job->firstChunk) {  /* flush frame header */
         size_t const hSize = ZSTD_compressContinue(job->cctx, dstBuff.start, dstBuff.size, job->srcStart, 0);
         if (ZSTD_isError(hSize)) { job->cSize = hSize; goto _endJob; }
@@ -271,8 +277,7 @@ struct ZSTDMT_CCtx_s {
     unsigned frameEnded;
     unsigned allJobsCompleted;
     unsigned long long frameContentSize;
-    const void* dict;
-    size_t dictSize;
+    ZSTD_CDict* cdict;
     ZSTDMT_jobDescription jobs[1];   /* variable size (must lies at the end) */
 };
 
@@ -324,6 +329,7 @@ static void ZSTDMT_releaseAllJobResources(ZSTDMT_CCtx* mtctx)
 size_t ZSTDMT_freeCCtx(ZSTDMT_CCtx* mtctx)
 {
     if (mtctx==NULL) return 0;   /* compatible with free on NULL */
+    ZSTD_freeCDict(mtctx->cdict);
     POOL_free(mtctx->factory);
     if (!mtctx->allJobsCompleted) ZSTDMT_releaseAllJobResources(mtctx); /* stop workers first */
     ZSTDMT_freeBufferPool(mtctx->buffPool);  /* release job resources into pools first */
@@ -442,8 +448,12 @@ static void ZSTDMT_waitForAllJobsCompleted(ZSTDMT_CCtx* zcs) {
     }
 }
 
-size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* zcs, const void* dict, size_t dictSize,
-                                   ZSTD_parameters params, unsigned long long pledgedSrcSize) {
+
+static size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
+                                    const void* dict, size_t dictSize, unsigned updateDict,
+                                    ZSTD_parameters params, unsigned long long pledgedSrcSize)
+{
+    ZSTD_customMem const cmem = { NULL, NULL, NULL };
     if (zcs->allJobsCompleted == 0) {   /* previous job not correctly finished */
         ZSTDMT_waitForAllJobsCompleted(zcs);
         ZSTDMT_releaseAllJobResources(zcs);
@@ -451,8 +461,12 @@ size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* zcs, const void* dict, size_t di
     }
     params.fParams.checksumFlag = 0;   /* current limitation : no checksum (to be lifted in a later version) */
     zcs->params = params;
-    zcs->dict = dict;
-    zcs->dictSize = dictSize;
+    if (updateDict) {
+        ZSTD_freeCDict(zcs->cdict); zcs->cdict = NULL;
+        if (dict && dictSize) {
+            zcs->cdict = ZSTD_createCDict_advanced(dict, dictSize, 0, params, cmem);
+            if (zcs->cdict == NULL) return ERROR(memory_allocation);
+    }   }
     zcs->frameContentSize = pledgedSrcSize;
     zcs->targetSectionSize = (size_t)1 << MAX(ZSTDMT_SECTION_LOGSIZE_MIN, (zcs->params.cParams.windowLog + 2));
     zcs->inBuffSize = zcs->targetSectionSize + ((size_t)1 << zcs->params.cParams.windowLog);
@@ -466,16 +480,23 @@ size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* zcs, const void* dict, size_t di
     return 0;
 }
 
+size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* zcs,
+                                const void* dict, size_t dictSize,
+                                ZSTD_parameters params, unsigned long long pledgedSrcSize)
+{
+    return ZSTDMT_initCStream_internal(zcs, dict, dictSize, 1, params, pledgedSrcSize);
+}
+
 /* ZSTDMT_resetCStream() :
  * pledgedSrcSize is optional and can be zero == unknown */
 size_t ZSTDMT_resetCStream(ZSTDMT_CCtx* zcs, unsigned long long pledgedSrcSize)
 {
-    return ZSTDMT_initCStream_advanced(zcs, zcs->dict, zcs->dictSize, zcs->params, pledgedSrcSize);
+    return ZSTDMT_initCStream_internal(zcs, NULL, 0, 0, zcs->params, pledgedSrcSize);
 }
 
 size_t ZSTDMT_initCStream(ZSTDMT_CCtx* zcs, int compressionLevel) {
     ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, 0);
-    return ZSTDMT_initCStream_advanced(zcs, NULL, 0, params, 0);
+    return ZSTDMT_initCStream_internal(zcs, NULL, 0, 1, params, 0);
 }
 
 
@@ -510,8 +531,9 @@ size_t ZSTDMT_compressStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, ZSTD_inBu
         zcs->jobs[jobID].srcStart = zcs->inBuff.buffer.start;
         zcs->jobs[jobID].srcSize = zcs->targetSectionSize;
         zcs->jobs[jobID].params = zcs->params;
-        zcs->jobs[jobID].dict = zcs->nextJobID == 0 ? zcs->dict : NULL;
-        zcs->jobs[jobID].dictSize = zcs->nextJobID == 0 ? zcs->dictSize : 0;
+        zcs->jobs[jobID].cdict = zcs->nextJobID==0 ? zcs->cdict : NULL;
+        zcs->jobs[jobID].dict = NULL;
+        zcs->jobs[jobID].dictSize = 0;
         zcs->jobs[jobID].fullFrameSize = zcs->frameContentSize;
         zcs->jobs[jobID].dstBuff = dstBuffer;
         zcs->jobs[jobID].cctx = cctx;
@@ -598,8 +620,9 @@ static size_t ZSTDMT_flushStream_internal(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* outp
         zcs->jobs[jobID].srcStart = zcs->inBuff.buffer.start;
         zcs->jobs[jobID].srcSize = srcSize;
         zcs->jobs[jobID].params = zcs->params;
-        zcs->jobs[jobID].dict = zcs->nextJobID == 0 ? zcs->dict : NULL;
-        zcs->jobs[jobID].dictSize = zcs->nextJobID == 0 ? zcs->dictSize : 0;
+        zcs->jobs[jobID].cdict = zcs->nextJobID==0 ? zcs->cdict : NULL;
+        zcs->jobs[jobID].dict = NULL;
+        zcs->jobs[jobID].dictSize = 0;
         zcs->jobs[jobID].fullFrameSize = zcs->frameContentSize;
         zcs->jobs[jobID].dstBuff = dstBuffer;
         zcs->jobs[jobID].cctx = cctx;
diff --git a/lib/compress/zstdmt_compress.h b/lib/compress/zstdmt_compress.h
index 7e9d07035..bdc4caabc 100644
--- a/lib/compress/zstdmt_compress.h
+++ b/lib/compress/zstdmt_compress.h
@@ -29,8 +29,8 @@ ZSTDLIB_API size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* cctx,
 
 ZSTDLIB_API size_t ZSTDMT_initCStream(ZSTDMT_CCtx* zcs, int compressionLevel);
 ZSTDLIB_API size_t ZSTDMT_resetCStream(ZSTDMT_CCtx* zcs, unsigned long long pledgedSrcSize);   /**< pledgedSrcSize is optional and can be zero == unknown */
-ZSTDLIB_API size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* zcs, const void* dict, size_t dictSize,
-                                   ZSTD_parameters params, unsigned long long pledgedSrcSize);  /**< pledgedSrcSize is optional and can be zero == unknown ; current limitation : no checksum */
+ZSTDLIB_API size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* zcs, const void* dict, size_t dictSize,   /**< dict can be released after init */
+                                   ZSTD_parameters params, unsigned long long pledgedSrcSize);  /**< params current limitation : no checksum ; pledgedSrcSize is optional and can be zero == unknown */
 
 ZSTDLIB_API size_t ZSTDMT_compressStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input);
 
diff --git a/lib/zstd.h b/lib/zstd.h
index a0d5c7856..52d65206c 100644
--- a/lib/zstd.h
+++ b/lib/zstd.h
@@ -572,6 +572,7 @@ ZSTDLIB_API size_t ZSTD_compressBegin(ZSTD_CCtx* cctx, int compressionLevel);
 ZSTDLIB_API size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel);
 ZSTDLIB_API size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize);
 ZSTDLIB_API size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned long long pledgedSrcSize);
+ZSTDLIB_API size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize);
 ZSTDLIB_API size_t ZSTD_compressContinue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);