flowgrate/dotnet

C# SDK for Flowgrate — Laravel-style database migrations with a fluent API.

How it works

Define migrations in C# using the fluent Blueprint API. The SDK serializes them to JSON and pipes to the Flowgrate CLI, which compiles and executes the SQL.

Requirements

• Flowgrate CLI — download the binary for your platform and put it on your PATH

# Linux (amd64)
curl -L https://github.com/flowgrate/core/releases/latest/download/flowgrate-linux-amd64 -o flowgrate
chmod +x flowgrate
sudo mv flowgrate /usr/local/bin/

# macOS (Apple Silicon)
curl -L https://github.com/flowgrate/core/releases/latest/download/flowgrate-darwin-arm64 -o flowgrate
chmod +x flowgrate
sudo mv flowgrate /usr/local/bin/

# macOS (Intel)
curl -L https://github.com/flowgrate/core/releases/latest/download/flowgrate-darwin-amd64 -o flowgrate
chmod +x flowgrate
sudo mv flowgrate /usr/local/bin/

# Or build from source
go install github.com/flowgrate/core@latest

Setup

1. Reference the SDK in your migrations project:

<ProjectReference Include="path/to/Flowgrate/Flowgrate.csproj" />

2. Add Program.cs:

using System.Reflection;
using Flowgrate;

FlowgrateRunner.Run(Assembly.GetExecutingAssembly());

3. Create flowgrate.yml next to your project:

Generate it with the CLI (recommended):

flowgrate init --db=postgres://user:pass@localhost/mydb

Or create manually:

database:
  url: postgres://user:pass@localhost/mydb

migrations:
  project: ./Migrations
  sdk: csharp

4. Generate and run migrations:

flowgrate make CreateUsersTable
flowgrate up

Migration anatomy

using Flowgrate;

public class _20260402_163107_CreateUsersTable : Migration
{
    public static string Version => "20260402_163107";

    public override void Up()
    {
        Schema.Create("users", table =>
        {
            table.Id();
            table.String("name");
            table.String("email", 100);
            table.Timestamps();
        });
    }

    public override void Down()
    {
        Schema.DropIfExists("users");
    }
}

Blueprint API reference

Create / drop table

Schema.Create("users", table => { ... });
Schema.Table("users", table => { ... });   // ALTER TABLE
Schema.Drop("users");
Schema.DropIfExists("users");

Column types

table.Id()                          // BIGSERIAL PRIMARY KEY
table.SmallInteger("level")         // SMALLINT
table.Integer("views")              // INTEGER
table.BigInteger("score")           // BIGINT
table.Decimal("price", 10, 2)       // NUMERIC(10, 2)
table.Float("rating")               // REAL
table.Double("latitude")            // DOUBLE PRECISION
table.Boolean("active")             // BOOLEAN
table.String("name")                // VARCHAR(255)
table.String("code", 10)            // VARCHAR(10)
table.Text("bio")                   // TEXT
table.Uuid("public_id")             // UUID
table.Json("settings")              // JSON
table.Jsonb("metadata")             // JSONB
table.Binary("avatar")              // BYTEA
table.Date("birthday")              // DATE
table.Time("opens_at")              // TIME
table.Timestamp("verified_at")      // TIMESTAMP

Column modifiers (chainable)

.Nullable()                         // NULL
.Default(value)                     // DEFAULT 'value'
.DefaultExpression("NOW()")         // DEFAULT NOW()  — raw SQL
.GeneratedUuid()                    // DEFAULT gen_random_uuid()
.Comment("description")
.Unique()                           // single-column unique index

Helpers

table.Timestamps()                  // created_at + updated_at TIMESTAMP DEFAULT NOW()
table.SoftDeletes()                 // deleted_at TIMESTAMP NULL
table.RememberToken()               // remember_token VARCHAR(100) NULL
table.Polymorphic("commentable")    // commentable_id BIGINT + commentable_type VARCHAR(255) + index
table.NullablePolymorphic("taggable")

Foreign keys

table.ForeignId("role_id")
     .Constrained("roles")          // REFERENCES roles(id)
     .OnDelete("cascade")
     .OnUpdate("cascade");

Indexes

table.Unique("email", "tenant_id").Name("uq_users_email_tenant");
table.Index("created_at");
table.Index("email", "name").Name("idx_users_search");

ALTER TABLE

Schema.Table("users", table =>
{
    table.AddColumn("phone").String(20).Nullable();
    table.ChangeColumn("name").String(500);
    table.DropColumn("avatar");
});

Running in Docker

docker compose exec sdk dotnet run --project /migrations | flowgrate up