---
title: ES|QL LINQ for .NET
description: Write C# LINQ expressions, get Elasticsearch ES|QL query strings. Type-safe, AOT compatible, with full IntelliSense and compile-time checking. Produces:...
url: https://docs-v3-preview.elastic.dev/esql-dotnet/esql
---

# ES|QL LINQ for .NET
Write C# LINQ expressions, get Elasticsearch [ES|QL](https://docs-v3-preview.elastic.dev/elastic/elasticsearch/tree/main/reference/query-languages/esql) query strings. Type-safe, AOT compatible, with full IntelliSense and compile-time checking.
```csharp
var results = await client.CreateQuery<LogEntry>()
    .From("logs-*")
    .Where(l => l.Level == "ERROR" && l.Duration > 1000)
    .OrderByDescending(l => l.Timestamp)
    .Take(50)
    .ToListAsync();
```

Produces:
```
FROM logs-*
| WHERE (log.level == "ERROR" AND duration > 1000)
| SORT @timestamp DESC
| LIMIT 50
```


## Two packages, one goal

The ES|QL LINQ support is split into two NuGet packages so you can choose the right level of dependency for your project.
**Most projects should install `Elastic.Clients.Esql`** -- it includes everything you need to build and execute ES|QL queries against an Elasticsearch cluster:
```shell
dotnet add package Elastic.Clients.Esql
```

This pulls in `Elastic.Esql` and `Elastic.Transport` automatically.
If you only need query string generation without any HTTP or transport dependency, install the translation library directly:
```shell
dotnet add package Elastic.Esql
```


| Package                                                                                     | What it does                                               | When to use it                                                      |
|---------------------------------------------------------------------------------------------|------------------------------------------------------------|---------------------------------------------------------------------|
| [Elastic.Clients.Esql](https://docs-v3-preview.elastic.dev/esql-dotnet/esql/package-client) | LINQ translation + query execution via `Elastic.Transport` | You want to run queries against a cluster and get results back      |
| [Elastic.Esql](https://docs-v3-preview.elastic.dev/esql-dotnet/esql/package-translation)    | LINQ-to-ES|QL translation only, zero dependencies          | You need string generation, a custom transport, or query inspection |


## Field name resolution

Field names are resolved automatically from your C# types using `System.Text.Json` conventions:
1. **`[JsonPropertyName]` attributes** -- if a property has `[JsonPropertyName("log.level")]`, that exact name is used in the generated ES|QL
2. **`JsonNamingPolicy`** -- if a `JsonNamingPolicy` is configured (e.g., `JsonNamingPolicy.CamelCase`), property names are transformed accordingly
3. **Default convention** -- without explicit configuration, property names are used as-is with camelCase conversion

```csharp
public class LogEntry
{
    [JsonPropertyName("@timestamp")]
    public DateTime Timestamp { get; set; } 

    [JsonPropertyName("log.level")]
    public string Level { get; set; }       

    public string Message { get; set; }     

    public long Duration { get; set; }      
}
```


### AOT-safe field resolution

For Native AOT compatibility, pass a source-generated `JsonSerializerContext` to the query provider. This ensures field names are resolved at compile time with zero reflection:
```csharp
[JsonSerializable(typeof(LogEntry))]
public partial class MyJsonContext : JsonSerializerContext;

var provider = new EsqlQueryProvider(MyJsonContext.Default);
var query = new EsqlQueryable<LogEntry>(provider)
    .From("logs-*")
    .Where(l => l.Level == "ERROR")
    .ToString();
```