LLM prompts https://github.com/preset-io/promptimize tokenization https://github.com/openai/tiktoken vector databases https://github.com/facebookresearch/faiss https://www.pinecone.io/ https://www.trychroma.com/ private https://bdtechtalks.com/2023/06/01/create-privategpt-local-llm/amp/ stacks serving LLMs https://github.com/ajndkr/lanarky https://github.com/deepset-ai/haystack (with Elasticsearch) full e2e example https://github.com/praj2408/Langchain-PDF-App-GUI no code GUI tools https://github.com/FlowiseAI/Flowise https://github.com/gmpetrov/databerry