llm-cpp v0.2.0: 26 single-header C++17 libraries for LLM features
https://github.com/Mattbusel/llm-cpp

1. Copy the headers you want from include/ into your project.
2. In exactly ONE .cpp file, define the implementation macro before including:
     #define LLM_CACHE_IMPLEMENTATION
     #include "llm_cache.hpp"
   Every other file just includes the header.
3. Compile as C++17. Headers marked libcurl also need -lcurl.

Try one with no API key:
  g++ -std=c++17 -Iinclude examples/offline/cache.cpp -o cache && ./cache
  cl /std:c++17 /EHsc /Iinclude examples\offline\cache.cpp

Header                  needs     implementation macro
llm_stream.hpp          libcurl   LLM_STREAM_IMPLEMENTATION
llm_retry.hpp           none      LLM_RETRY_IMPLEMENTATION
llm_cost.hpp            none      LLM_COST_IMPLEMENTATION
llm_cache.hpp           none      LLM_CACHE_IMPLEMENTATION
llm_format.hpp          none      LLM_FORMAT_IMPLEMENTATION
llm_json.hpp            none      LLM_JSON_IMPLEMENTATION
llm_parse.hpp           none      LLM_PARSE_IMPLEMENTATION
llm_embed.hpp           libcurl   LLM_EMBED_IMPLEMENTATION
llm_rag.hpp             libcurl   LLM_RAG_IMPLEMENTATION
llm_rank.hpp            libcurl   LLM_RANK_IMPLEMENTATION
llm_compress.hpp        none      LLM_COMPRESS_IMPLEMENTATION
llm_batch.hpp           libcurl   LLM_BATCH_IMPLEMENTATION
llm_log.hpp             none      LLM_LOG_IMPLEMENTATION
llm_trace.hpp           none      LLM_TRACE_IMPLEMENTATION
llm_pool.hpp            none      LLM_POOL_IMPLEMENTATION
llm_mock.hpp            none      LLM_MOCK_IMPLEMENTATION
llm_eval.hpp            libcurl   LLM_EVAL_IMPLEMENTATION
llm_ab.hpp              libcurl   LLM_AB_IMPLEMENTATION
llm_chat.hpp            libcurl   LLM_CHAT_IMPLEMENTATION
llm_agent.hpp           libcurl   LLM_AGENT_IMPLEMENTATION
llm_vision.hpp          libcurl   LLM_VISION_IMPLEMENTATION
llm_template.hpp        none      LLM_TEMPLATE_IMPLEMENTATION
llm_router.hpp          none      LLM_ROUTER_IMPLEMENTATION
llm_guard.hpp           none      LLM_GUARD_IMPLEMENTATION
llm_audio.hpp           libcurl   LLM_AUDIO_IMPLEMENTATION
llm_finetune.hpp        libcurl   LLM_FINETUNE_IMPLEMENTATION

Headers fetched from each library's main branch on 2026-09-28.
