AI · alternatives · 2026
24 alternatives to Memora – A Vector DB with Multistage Reranking
Hey HN, Matusa here! A friend and I have built Memora. Memora is a vector database with built-in multistage reranking, which can significantly improve search accuracy over semantic search. It also features a proprietary embedding model tailored for RAG use cases — where there's a structural mismatch between the content stored and the query used for searching (hence why HyDE works well). Memora started because we were working on a stealth AI startup where we used an agent that would query into a vector DB, but it would take multiple tries for the agent to find what it needed (20% of the time…
Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Prices are shown for the 1 we have checked on their own sites, 1 of them free or with a free tier. Memora – A Vector DB with Multistage Reranking launched in 2023; newer entries below may have overtaken it.
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Hey there HN! We’re Antonio, Luca, and Yuhang, and we’re excited to introduce Fast GraphRAG, an open-source RAG approach that leverages knowledge graphs and the 25 years old PageRank for better information retrieval and reasoning. Building a good RAG pipeline these days takes a lot of manual optimizations. Most engineers intuitively start from naive RAG: throw everything in a vector database and hope that semantic search is powerful enough. This can work for use cases where accuracy isn’t too important and hallucinations are tolerable, but it doesn’t work for more difficult queries that…
2024 · github.com · its alternatives →
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Memoriafree tier, from $9.99/mo▲156Search photos by text, speech, object & faces. 100% offline.
Aug 2026 · memoria.anasouh.fr · its alternatives →
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Hey HN! We are building Epsilla (https://github.com/epsilla-cloud/vectordb), an open-source, self-hostable vector database for semantic similarity search that specializes in low query latency. When do we need a vector database? For example, GPT-3.5 has a 16k context window limit. If we want to let it answer a question about a 300 page book, we cannot put the whole book content into the context. We have to choose the sections of the book that are most relevant to the question. Vector database is specialized at ranking and picking the most relevant content from a large pool…
2023 · github.com · its alternatives →
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Hey HN! I built a proof-of-concept for AI memory using Git instead of vector databases. The insight: Git already solved versioned document management. Why are we building complex vector stores when we could just use markdown files with Git's built-in diff/blame/history? How it works: Memories stored as markdown files in a Git repo Each conversation = one commit git diff shows how understanding evolves over time BM25 for search (no embeddings needed) LLMs generate search queries from conversation context Example: Ask "how has my project evolved?" and it uses git diff to show actual…
2025 · github.com · its alternatives →
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Hey HN, we want to share HelixDB (https://github.com/HelixDB/helix-db/), a project a college friend and I are working on. It’s a new database that natively intertwines graph and vector types, without sacrificing performance. It’s written in Rust and our initial focus is on supporting RAG. Here’s a video runthrough: https://screen.studio/share/szgQu3yq. Why a hybrid? Vector databases are useful for similarity queries, while graph databases are useful for relationship queries. Each stores data in a way that’s best for its main type of query (e.g.…
2025 · github.com · its alternatives →
- 6LA
We are excited to share Lantern! Lantern is a PostgreSQL vector database extension for building AI applications. Install and use our extension here: https://github.com/lanterndata/lantern We have the most complete feature set of all the PostgreSQL vector database extensions. Our database is built on top of usearch — a state of the art implementation of HNSW, the most scalable and performant algorithm for handling vector search. There’s three key metrics we track. CREATE INDEX time, SELECT throughput, and SELECT latency. We match or outperform pgvector and pg_embedding…
2023 · docs.lantern.dev · its alternatives →
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Memori▲168Persistent memory from agent trace, not just conversation
May 2026 · memorilabs.ai · its alternatives →
- 8IM
2020 · memordo.com · its alternatives →
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Memoriq▲130Archive and search saved conversations from ChatGPT, Claude, Gemini, and Grok in one encrypted AI chat vault.
Jun 2026 · memoriq.me · its alternatives →
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I've been working on Polign and built a small prototype around something I've been thinking about with agent memory. I have built a lightweight/stateless vector db + BM25 search which works really well with typed facts and structured queries. It uses your own S3, or GCS bucket as primary storage, and restarting a node is fairly quick. Demo + writeup: https://polign.com/blog-edge-agent-memory Live search demo: https://demo.polign.com Docs: https://polign.com
Aug 2026 · polign.com · its alternatives →
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Hey HN! We're Phil and Ming, co-founders of Retake (https://github.com/getretake/retake). Retake is an open source tool that adds keyword and semantic (i.e hybrid) search to databases. We’ve started by extending the capabilities of Postgres with an SDK for lightning-fast queries. We built Retake to fix two issues: keeping vectors in sync with Postgres in real time is difficult, and most vector databases aren’t built for hybrid search. A quick refresher: “keyword search” refers to a technique where results are scored based on the appearance of exact words or terms.…
2023 · github.com · its alternatives →
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Memora gives AI the ability to recall memories during interactions, just like humans do subconsciously. For now, it’s just text-based memories, but our vision extends to the full spectrum of human memory: emotions, audio, video. Key Features: Built-in multi-tenancy for managing multiple organizations, users, and agents. Time-stamped memories to track how information evolves over time. Scalable, modular, and developer-friendly design. GitHub: https://github.com/ELZAI/memora Install: pip install memora-core We’re looking for feedback and contributions, let’s change how we…
2025 · github.com · its alternatives →
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Memora▲4AI coding agent. Single binary. Any model. Full audit trail.
May 2026 · radotsvetkov.github.io · its alternatives →
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Hey HN! I’ve recently open-sourced Pyversity, a lightweight library for diversifying retrieval results. Most retrieval systems optimize only for relevance, which can lead to top-k results that look almost identical. Pyversity efficiently re-ranks results to balance relevance and diversity, surfacing items that remain relevant but are less redundant. This helps with improving retrieval, recommendation, and RAG pipelines without adding latency or complexity. Main features: - Unified API: one function (diversify) supporting several well-known strategies: MMR, MSD, DPP, and COVER (with more to…
2025 · github.com · its alternatives →
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Hey HN! I'm Arindam, part of the team behind Memori (https://memori.gibsonai.com/). Memori adds a stateful memory engine to AI agents, enabling them to stay consistent, recall past work, and improve over time. With Memori, agents don’t lose track of multi-step workflows, repeat tool calls, or forget user preferences. Instead, they build up human-like memory that makes them more reliable and efficient across sessions. We’ve also put together demo apps (a personal diary assistant, a research agent, and a travel planner) so you can see memory in action. Current LLMs are stateless…
2025 · github.com · its alternatives →
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Vector databases store memories. They don't manage them. After 10k memories, recall quality degrades because there's no consolidation, no forgetting, no conflict resolution. Your AI agent just gets noisier. YantrikDB is a cognitive memory engine — embed it, run it as a server, or connect via MCP. It thinks about what it stores: consolidation collapses duplicate memories, contradiction detection flags incompatible facts, temporal decay with configurable half-life lets unimportant memories fade like human memory does. Single Rust binary. HTTP + binary wire protocol. 2-voter + 1-witness HA…
Apr 2026 · github.com · its alternatives →
- 18MS
2019 · memos.org · its alternatives →
- 19SA
Hi HN, I’m Tullie, founder of Shaped. Previously, I was a researcher at Meta AI, worked on ranking for Instagram Reels, and was a contributor to PyTorch Lightning. We built ShapedQL because we noticed that while retrieval (finding 1,000 items) has been commoditized by vector DBs, ranking (finding the best 10 items) is still an infrastructure problem. To build a decent for you feed or a RAG system with long-term memory, you usually have to put together a vector DB (Pinecone/Milvus), a feature store (Redis), an inference service, and thousands of lines of Python to handle business logic…
Jan 2026 · playground.shaped.ai · its alternatives →
- 20AG
This is a vector index I built that supports insertion and k-nearest neighbors (k-NN) querying, optimized for GPUs. It operates entirely in CUDA and can process queries on half a billion vectors in under 200 milliseconds. The codebase is structured as a standalone library with an HTTP API for remote access. It’s intended for high-performance search tasks—think similarity search, AI model retrieval, or reinforcement learning replay buffers. The codebase is located at https://github.com/rodlaf/BinaryGPUIndex.
2025 · rlafuente.com · its alternatives →
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MemoryOS▲3Hybrid AI Memory: Vector RAG meets Knowledge Graphs
Apr 2026 · github.com · its alternatives →
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Extremely memory-efficient vector database. Contribute to D-Star-AI/minDB development by creating an account on GitHub.
2024 · github.com · its alternatives →
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Also compare
- FastGraphRAG – Better RAG using good old PageRank alternatives
- Memoria alternatives
- Epsilla – Open-source vector database with low query latency alternatives
- I replaced vector databases with Git for AI memory (PoC) alternatives
- HelixDB – Open-source vector-graph database for AI applications (Rust) alternatives
- Lantern – a PostgreSQL vector database for building AI applications alternatives
Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →