# Training 100x Cheaper Retrieval models Neon and Castform

DevFeed: [Training 100x Cheaper Retrieval models Neon and Castform](<https://devfeed.tech/articles/training-100x-cheaper-retrieval-models-neon-and-castform-5343.md>)

Original publisher: [Read original article](<https://neon.com/blog/how-castform-neon-beats-frontier-models-on-price-and-efficiency>)

Author: Pranav Aurora

Published: 2026-08-05T12:00:00Z

Content type: article

Language: en

Sources: [Blog -- Neon Docs](<https://devfeed.tech/sources/blog-neon-docs.md>)

Topics: [Retrieval Augmented Generation (RAG)](<https://devfeed.tech/topics/retrieval-augmented-generation-rag.md>), [Training AI Models](<https://devfeed.tech/topics/training-ai-models.md>), [Machine learning](<https://devfeed.tech/topics/machine-learning.md>), [Open Source Models & Datasets](<https://devfeed.tech/topics/open-source-models-datasets.md>), [Large Language Model](<https://devfeed.tech/topics/llm.md>), [Open Source](<https://devfeed.tech/topics/open-source.md>), [Latency](<https://devfeed.tech/topics/latency.md>), [Database](<https://devfeed.tech/topics/database.md>)

Tags: [agentic](<https://devfeed.tech/tags/agentic.md>), [agents](<https://devfeed.tech/tags/agents.md>), [cost](<https://devfeed.tech/tags/cost.md>), [embedding](<https://devfeed.tech/tags/embedding.md>), [infra](<https://devfeed.tech/tags/infra.md>), [llms](<https://devfeed.tech/tags/llms.md>), [machine-learning](<https://devfeed.tech/tags/machine-learning.md>), [model](<https://devfeed.tech/tags/model.md>), [models](<https://devfeed.tech/tags/models.md>), [open-source](<https://devfeed.tech/tags/open-source.md>), [performance](<https://devfeed.tech/tags/performance.md>), [post-training](<https://devfeed.tech/tags/post-training.md>), [product](<https://devfeed.tech/tags/product.md>), [rag](<https://devfeed.tech/tags/rag.md>), [retrieval](<https://devfeed.tech/tags/retrieval.md>), [rl](<https://devfeed.tech/tags/rl.md>), [scale](<https://devfeed.tech/tags/scale.md>), [search](<https://devfeed.tech/tags/search.md>), [systems](<https://devfeed.tech/tags/systems.md>), [tools](<https://devfeed.tech/tags/tools.md>), [training](<https://devfeed.tech/tags/training.md>)

## AI overview

The article explains how Castform uses reinforcement-learning post-training to improve open-weight models for agentic retrieval. It contrasts multi-step retrieval with one-shot embedding search, emphasizing the cost and latency of repeated frontier-model calls and the potential for smaller open models to perform specific search tasks more cheaply.

## Source excerpt

"Most teams' best training data is just sitting in their databases. The problem is that turning raw data into something usable is hard, and letting agents read, search, and mutate data cheaply at scale requires advanced infra. Pointing Castform at Neon skips both." -- Ying Hang Seah, cofounder, Castform