Awesome Open Source
Awesome Open Source

GitHub Readme Stats


A brand new, fast, and lightweight ORM. | Documentation

Nuget Nuget GitHub issues Coverage Status GitHub Discord

Venflow is currently undergoing a full rewrite, check the progress here.


Venflow is a brand new ORM, written from the ground up to try and provide an alternative to EF-Core and many other ORMs. It allows you to define Models and their relations with each other. Additionally it maps all queries on its own while still maintaining great performance.

Lets face it, EF-Core is awesome, but it can be slow, really slow. However this library tries to overcome that by providing similar features while maintaining great performance. Venflow comes with a very similar UX to Dapper and EF-Core, in order to keep the learning curve as low as possible.


  • Simple change-tracking for update operations
  • Autogenerated Inserts
  • Autogenerated Deletes
  • Autogenerated Query Materializer, Join Generator
  • SQL Injection safe string Interpolated SQL
  • Refactorable and maintainable SQL


The simplest way to do so, is by giving the project a ⭐️ and sharing the project to others. How you can help other than that? This can be done in numerous ways, over on the issue section, such as:

  • Creating feature requests
  • Creating pull requests
  • Reporting bugs

For more information take a look at our contribution guideline.


Venflow can currently be downloaded on

Also you can install it via the Package Manager Console:

Install-Package Venflow


Benchmarking ORM's isn't an easy task, since there are a bunch of different factors which can alter the result in one way or another. I do not present any beautiful graphs here simply because they would get too complex and it would require too many graphs to remain practical. This is also the reason why I tried to come up with a composite number based on benchmark results. If you still want check all the individual benchmarks, which you definitely should, the source code can be found here and the results as .csv and .md are over here.

Lets just directly hop into the composite numbers of each tested ORM.

ORM Name Composite Score* Mean Score* Allocation Score*
#1 Dapper 2,822 2,707 0,115
#2 Venflow 4,658 3,786 0,872
#3 RepoDb 51,532 49,333 2,199
#4 EFCore 113,686 94,394 19,292

* Lower is considered to be better ** Do have missing benchmark entries for specific benchmark groups and therefor might have either better or worse scores.

Now how do I calculate this magic number? The formula is as following:

compositeScore = ((meanTime / lowestMeanTimeOfGroup - 1) + (allocation / lowestAllocationOfGroup - 1) / 10)

A group is considered to be a list of benchmark entries which are inside the same file and have the same count and target framework. Now as some ORM's don't have any benchmarks entries for specific benchmark groups it will instead take the lowest mean and the lowest allocation from this group. The source code of the calculation can be found here.


The benchmarks themselves or even the calculation of the composite numbers may not be right and contain bugs. Therefor take these results with a grain of salt. If you find any bugs inside the calculations or in the benchmarks please create an issue and I'll try to fix it ASAP.

Is this package for you?

Especially for ORM's it is becoming a harder challenge than ever before, to choose the right one for you. This project tries to be as transparent as possible, so if any of the following points apply to you or your project, choose a different ORM at least for your current project.

  • You are feeling unsure about writing raw SQL.
  • You are using a database other than PostgreSQL.
  • You rely on a code-first implementation.
  • You require Linq2Sql.

indicates that this point might change it the future

But why should I use Venflow over EF-Core anyway?

Obviously this project is nowhere near as mature as EF-Core as it already covers all your needs. However Venflow is all about performance in every way. You might ask yourself now, why would I even care? Well, especially for Web-Apps it really matters! Your response times for all requests involving some sort of Database interaction will immediately decrease. This also means that your application will not take up as much resources on your server. Obviously this only is applicable, if the website encounters somewhat high traffic.

But why should I use Venflow over Dapper anyway?

Venflow supports a lot more things out of the box, such as automatically generated Delete/Insert statements, as well as simple change tracking to easily update specific entities. Another big factor, which probably is one of the biggest differences to Dapper, are the automatically generated materializers for queries. A lot of the times a materializer generated by Venflow will be faster, especially for bigger tables, than a hand written Dapper one. This is due to the nature of how Dapper and Venflow handle parsing of SQL results.

Basic usage

As already mentioned, Venflow tries to keep the learning curve from other ORM's as low as possible, therefore a lot of patterns will seem familiar to either EFCore or Dapper.

Basic configuration

The official documentation and guides can be found here

In Venflow you are reflecting your PostgreSQL database with the Database class, which will host all of your tables. This class represents a connection to your database and therefor doesn't support multi threaded use. In the following example we will configure a database containing two tables, Blogs and Posts. One Blog contains many posts and a post contains a single Blog.

public class BlogDatabase : Database
    public Table<Blog> Blogs { get; set; }
    public Table<Post> Posts { get; set; }

    public BlogDatabase() : base("Your connection string.")

Now lets configure the actual relation between Blogs and Posts through the EntityConfiguration<T> class. In the Configure , method you can configure several things such as the name of the table this entity should map to and much more. These configuration classes do automatically get discovered, if they are in the same assembly as the Database class. If they are not in the same assembly, you can override the Configure method in the Database class which passes in a DatabaseOptionsBuilder, which will allow you to specify assemblies which should also be searched for entity configurations.

public class BlogConfiguration : EntityConfiguration<Blog>
    protected override void Configure(IEntityBuilder<Blog> entityBuilder)
        entityBuilder.HasMany(b => b.Posts)
                     .WithOne(p => p.Blog)
                     .UsingForeignKey(p => p.PostId);

An instance of your Database class exposes the underlying connection and the actual CRUD builders. In the example below you can see how you would query a set of Blogs with their posts.

await using var database = new BlogDatabase(); // You should register a Transient/Scoped your DI Container.

const string sql = @"SELECT * FROM ""Blogs"" JOIN ""Posts"" ON ""Posts"".""BlogId"" = ""Blogs"".""Id""";

var blogs = await database.Blogs.QueryBatch(sql).JoinWith(x => x.Posts).QueryAsync();
// Or
var blogs = await database.Blogs.QueryBatch<Post>((b, p) => $"SELECT * FROM {b} JOIN {p} ON {p.BlogId} = {b.Id}").QueryAsync();

With parameters, this could be written in one of the following two ways.

var id = 1;

var blogs = await database.Blogs.QueryBatch(b => $"SELECT * FROM {b} WHERE {b.Id} = {id}").QueryAsync();
// Or
var blogs = await database.Blogs.QueryInterpolatedBatch(@$"SELECT * FROM ""People"" WHERE ""Id"" = {id}").QueryAsync();

More on topic of querying and other CRUD operations can be found over on the docs.

Road map

  • Composed PK support
  • Direct support for many to many relations
  • Support for materialized Views
  • Bulk operation support from PostgreSQL.Bulk
  • Code-First
  • AOT proxy/entity generation with Source Generators


I also want to mention all the other great packages out there, build by awesome people, which helped with building Venflow in one way or another such as being open-source.

Awesome people which helped in the development

  • LunarLite for helping me with highly complex logically issues.
  • AnotherZane for being one of the early preview testers.
  • Jas and Altrius for providing general surface API ideas.


Contact information

If you feel like something is not working as intended or you are experiencing issues, feel free to create an issue. Also for feature requests just create an issue. For further information feel free to send me an email at [email protected] or message me on Discord 24_minutes#7496.


I wanna thank JetBrains for providing me and the project with a free Open Source license for their whole JetBrains suite. Their tools greatly improve the development speed of this project. If you want to get a free Open Source license for your own project and their collaborators, visit their Open Source page.

Alternatives To Venflow
Select To Compare

Alternative Project Comparisons
Related Awesome Lists
Top Programming Languages
Top Projects

Get A Weekly Email With Trending Projects For These Topics
No Spam. Unsubscribe easily at any time.
C Sharp (169,379
Postgres (23,947
Postgresql (23,947
Sql (22,314
Benchmark (11,679
Orm (5,933
Dapper (665
Objectmapper (273
Orm Framework (143
Orm Library (63
Postgresql Orm (7