# Ollama Holes ![image](https://github.com/user-attachments/assets/649ffcd2-0560-47d6-bbbe-74bae08cbb70) ## Introduction This is an example of a typed-hole plugin for GHC that uses the [Ollama](https://ollama.com/) to host a local LLM to fill in holes in Haskell code. Before using this plugin, make sure you have the Ollama CLI installed and the model you want to use is available. You can install the Ollama CLI by following the instructions at [https://ollama.com/download](https://ollama.com/download), and you can install the default model (gemma3:27b) by running `ollama pull gemma3:27b`. Note that the speed and quality of the hole-fits generated by the plugin depends on the model you use, and the default model requires a GPU to run efficiently. For a smaller model, we suggest `gemma3:4b-it-qat`, or `deepcoder:1.5b`. This plugin is also availble on Hackage [https://hackage.haskell.org/package/ollama-holes-plugin](https://hackage.haskell.org/package/ollama-holes-plugin) ## Example Given ```haskell {-# OPTIONS_GHC -fplugin=GHC.Plugin.OllamaHoles #-} {-# OPTIONS_GHC -fplugin-opt=GHC.Plugin.OllamaHoles:model=gemma3:27b #-} {-# OPTIONS_GHC -fplugin-opt=GHC.Plugin.OllamaHoles:n=5 #-} module Main where import Data.List main :: IO () main = do let k = (_b :: [Int] -> [String]) print (k [1,2,3]) ``` We get the following output: ```text Main.hs:12:20: error: [GHC-88464] • Found hole: _b :: [Int] -> [String] Or perhaps ‘_b’ is mis-spelled, or not in scope • In the expression: _b :: [Int] -> [String] In an equation for ‘k’: k = (_b :: [Int] -> [String]) In the expression: do let k = (_b :: [Int] -> [String]) print (k [1, 2, ....]) • Relevant bindings include k :: [Int] -> [String] (bound at Main.hs:12:15) main :: IO () (bound at Main.hs:12:1) Valid hole fits include \x -> map show x map (show) \x -> map (\y -> "Number: " ++ show y) x \x -> replicate (length x) "Hello" [] | 12 | main = do let k = (_b :: [Int] -> [String]) | ^^ Error: cabal: Failed to build exe:main from OllamaHolesTest-1.0.0. ``` ## Installation 1. Install [Ollama](https://ollama.com/download) 2. Install the `gemma3:27b` model (or any other model you prefer) using the following command: ```bash ollama pull gemma3:27b ``` 3. Clone this repository and navigate to the directory, and build the project using: ```bash cabal build ``` 4. Run the example using: ```bash cabal build Test ``` 5. Enjoy! If you want to change the underlying model, make sure to pass the model name via the plugin arguments (see example) ## OpenAI and Gemini backends The plugin now supports using the OpenAI API and Gemini APIs to generate valid hole fits. Simply set the backend flag `-fplugin-opt=GHC.Plugin.OllamaHoles:backend=openai`, or `-fplugin-opt=GHC.Plugin.OllamaHoles:backend=gemini`, and make sure that you have the `OPENAI_API_KEY` or `GEMINI_API_KEY` set in your environment. To use with any other OpenAI compatible api (like groq or OpenRouter), simply set `-fplugin-opt=GHC.Plugin.OllamaHoles:backend=openai`, and `-fplugin-opt=GHC.Plugin.OllamaHoles:openai_base_url=https://api.groq.com/openai`, `-fplugin-opt=GHC.Plugin.OllamaHoles:openai_key_name=GROQ_API_KEY`,