⚡ Autypo

Blazing-fast autocomplete and typo-tolerant search for .NET

Autypo is a powerful, developer-friendly search engine for autocomplete, fuzzy matching, and short-string lookups. Whether you're building a product search bar, form helper, or CLI — Autypo makes it effortless to deliver typo-tolerant, fast, and intelligent user experiences.

📚 Table of Contents

• Getting Started
• Installation
• Features
• Limitations
• Perfect For
• Learning Resources
• Samples
• Benchmarks
• Project Structure
• Support and Feedback
• License

✨ Getting Started

✅ Basic Setup — In 30 Seconds

Autypo works out-of-the-box — no config required. Just provide your data and start getting intelligent completions.

using Autypo;
using Autypo.Configuration;

string[] movies = [
    "The Lord of the Rings: The Return of the King",
    "Star Wars: Return of the Jedi",
    "Batman Returns"
];

IAutypoComplete autypoComplete = await AutypoFactory.CreateCompleteAsync(config => config
    .WithDataSource(movies));

IEnumerable<string> suggestions = autypoComplete.Complete("retur of the");
// → "Star Wars: Return of the Jedi", "The Lord of the Rings: The Return of the King"

suggestions = autypoComplete.Complete("bamman rets");
// → "Batman Returns"

No tokenization setup. No fuzzy matching config. Just smart results.

✅ ASP.NET Core Setup with Background Indexing

For real-world apps, Autypo integrates seamlessly with ASP.NET Core and supports background indexing, multi-field search, and dependency-injected data sources.

using Autypo;
using Autypo.AspNetCore;
using Autypo.Configuration;

builder.Services.AddScoped<ProductsLoader>();

builder.Services.AddAutypoSearch<Product>(config => config
    .WithDataSource(serviceProvider => serviceProvider.GetRequiredService<ProductsLoader>())
    .WithBackgroundLoading(UninitializedBehavior.ReturnEmpty)

    .WithIndex(product => product.Name, index => index
        .WithAdditionalKeys(product => [product.Description]) // Index name + description
        .WithUnorderedTokenOrdering() // Order of words doesn't matter
        .WithPartialTokenMatching() // Partial queries still match
        // ... and many more configuration options!
    ));

Define a search endpoint using dependency-injected Autypo:

app.MapGet("/products/search", async (
    [FromQuery] string query,
    [FromServices] IAutypoSearch<Product> search) =>
{
    var results = await search.SearchAsync(query);
    return results.Select(r => r.Value);
});

Example Query:

GET /products/search?query=fngerprint usb recogn

Example Result:

[
 {
   "code": "A1067",
   "name": "Fingerprint USB",
   "description": "Secure USB flash drive with fingerprint encryption"
 },
]

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📦 Installation

Autypo is available on NuGet.

For ASP.NET Core integration (includes the core engine):

dotnet add package Autypo.AspNetCore

For standalone or non-web scenarios (e.g., console apps, background jobs):

dotnet add package Autypo

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💡 Features

Autypo gives you fast, typo-tolerant search with modern developer ergonomics — zero config to start, but extreme tuning if you need it.

🧠 Intelligent Matching

• Typo-tolerant by default — fuzzy, partial, and out-of-order input
• Token-level matching control (prefix, fuzziness)
• Opt-in partial matching and out-of-order input
• Built to rank “real world” input
• Multi-index support with priority-based short-circuiting

🔧 Deeply Configurable

• Index multiple fields (e.g. name + description)
• Plug in custom scorers, filters, and match policies
• Add tokenizers and analyzers (N-grams, stemming, etc)
• Per-query tuning for fuzziness, partial match, max results

⚙️ Production-Ready

• Blazing-fast in-memory autocomplete via IAutypoComplete
• Full-featured, multi-index search engine via IAutypoSearch<T>
• Eager, background, or lazy indexing — your choice
• Refresh indexes at runtime with AutypoRefreshToken
• Async-first, thread-safe, allocation-conscious

🌐 Framework-Friendly

• ASP.NET Core integration with full DI support
• Blazor Server–ready (ideal for typeahead inputs)
• Fully .NET-native — no native bindings, no hosted servers

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✅ Open source & MIT licensed
🛡️ Built for scale and safety
🎉 Developer-first design

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⚠️ Limitations

Autypo is intentionally designed for short-text and autocomplete scenarios — not full-text search.

• Documents are limited to 64 tokens max (e.g., product names, commands, short descriptions)
• In-memory indexing is fast and efficient, but may not suit massive corpora or multi-megabyte documents
• Autypo is not intended for long-form text search — for that, consider other tools.

This tradeoff is deliberate: it keeps Autypo incredibly fast, predictable, and ideal for UX-critical search.

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🎯 Perfect For

• E-commerce product & SKU search
• Admin panel filtering and form helpers
• Smart command palettes
• CLI "Did You Mean?" suggestions
• Blazor autocomplete inputs
• Live-search over reference data (countries, tags, part numbers)
• Fuzzy full-text matching over short documents

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📚 Learning Resources

📖 Guides

Guide	Description
ASP.NET Core Integration	End-to-end setup with dependency injection and hosted services
Indexing & Data Loading	Data sources, refresh tokens
Search & Matching	Customize fuzzy logic, token ordering and more
Text Analysis & Tokenization	Configure tokenizers, transformers, and analyzers
Custom Scoring & Filtering	Enrich matches with metadata and business logic

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💻 Samples

Sample	What it demonstrates
"Did You Mean?" Console Demo	Interactive CLI Helper – Suggests valid commands with fuzzy matching
ASP.NET Core Search API	Product Search – REST API with background indexing and multi-field matching
Blazor City Autocomplete	Real-Time Search UI – Typeahead with typo tolerance and reindexing

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📊 Benchmarks

Autypo competes head-to-head with Lucene and outperforms many .NET libraries for short-string search:

Library	Multi-Token	Index Time	Search Time	Avg/Search
Autypo	✅ Yes	163 ms	3.34 s	1.33 ms
Lucene (Fuzzy)	✅ Yes	776 ms	2.91 s	1.16 ms
Lucene (Suggest)	❌ No	1.12 s	503 ms	0.20 ms
Levenshtypo*	❌ No	25 ms	312 ms	0.12 ms
FuzzyWuzzy	❌ No	1 ms	4m 49s	92.56 ms

* Levenshtypo is the fuzzy string search library that powers Autypo’s low-level approximate matching engine. It supports typo-tolerant single-token search using optimized Tries and Levenshtein Automata.

⚠️ See full benchmark repo and disclaimer →

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📁 Project Structure

/src
  └── Autypo/                   # Core library
  └── Autypo.AspNetCore/        # ASP.NET Core integration
  └── Autypo.Benchmarks/        # Microbenchmarks
  └── Autypo.IntegrationTests/
  └── Autypo.UnitTests/
  └── Autypo.Aot/               # Ensures that Autypo works in AOT scenarios
  
/samples
  └── ApiSearchProducts/        # REST API example
  └── BlazorCities/             # Blazor Server autocomplete
  └── ConsoleDidYouMean/        # CLI demo

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💬 Support and Feedback

🧠 Have a question?
💡 Got feedback?
🐛 Found a bug?

Open an issue or start a discussion. We'd love to hear from you.

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⚖️ License

Autypo is released under the MIT License.

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🙋‍♂️ What's in a Name?

Autocomplete + Typo-tolerance = Autypo.

Simple name, serious power.

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Built for modern .NET developers.