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AI · June 15, 2025

Semcache – I built a semantic cache in Rust

Have a look at my semantic caching project! It's built to easily integrate in existing LLM workflows, you can use it as a proxy where the cache forwards missed requests without modification to a specified upstream, automatically updating it's cache with the response. You can also use it as a cache-aside cache with a provided python library. It works by computing embedding vectors of input queries, and matches them to seen query + response pairs using a vector store. Everything is in-memory, so it should be blazing fast :)

Semcache – I built a semantic cache in Rust launched on June 15, 2025 with 5 votes and more than 75% of that year's launches. The site was still online in September 2026, 1 year on.

What it does

Semantic caching layer for your LLM applications. Reuse responses and reduce token usage. - sensoris/semcache

semcache is a semantic caching layer for your LLM applications. docker run -p 8080:8080 semcache/semcache:latest Configure your application e.g with the OpenAI Python SDK: from openai import OpenAI # Point to your Semcache host instead of OpenAI client = OpenAI ( base_url = "http://localhost:8080" , api_key = "your-key" ) # Cache miss - continues to OpenAI response = client . chat . completions . create ( model = "gpt-4o" , messages = [{ "role" : "user" , "content" : "What is the capital of France?" }] ) # Cache hit - returns instantly response = client . chat . completions . create ( model = "gpt-4o" , messages = [{ "role" : "user" , "content" : "Tell me France's capital city" }] ) Node.js…from github.com

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