A code-first path off SQL Server Integration Services

A C# replacement for SSIS

SSIS is still fast. It is no longer where Microsoft invests. ETLBox keeps the Control Flow / Data Flow split you already know — as C# you can diff, test, and ship in CI.

A lot of production ETL still lives in SSIS because the engine is fast and operators know how to restart a package. New product energy sits in Azure Data Factory, Synapse, and Fabric. The expensive moment is the one where a cloud move or a hiring constraint forces the question, and the only packages you have are designer canvases. ETLBox is the code-first way out — not another designer.

SSIS

Same mental model. Different medium.

Control Flow is everything around the stream: create tables, truncate staging, run SQL, write counts. Data Flow is source → transform → destination, with a second path for rows that should not land. In ETLBox that is SqlTask around a linked network of components, started with Network.Execute. The toolbox jobs stay. The package becomes C#.

ETLBox

The package is code

Git diffs you can review
Unit tests and CI/CD
Streaming engine and bulk loads
Lookup, split, merge join, multicast
Runs anywhere .NET runs

SSIS

The package is a canvas

A .dtsx diff is XML, not a reviewable patch
Script Components nobody runs in a test
Fast engine, stalled product
One extra Lookup rearranges the canvas
Tied to SQL Server / Integration Runtime

ADF

ADF is the official successor. It is not the better designer.

For cloud-native, mostly linear pipelines, Azure Data Factory is a reasonable default. That is not the shape of most long-lived SSIS estates. Those packages are dense: Execute SQL around a Data Flow, lookups with no-match outputs, row redirection, Script Components because the toolbox cannot express the rule. Mapping Data Flows make that awkward. The SSIS Integration Runtime is a bridge so existing packages can keep running in Azure. It is not a destination.

ETLBox

Leave the designer

C#, not a second expression language
The same Control Flow / Data Flow split
Range lookups the SSIS toolbox cannot do
Debug in Visual Studio or Rider
On-prem, cloud, or a container — your call

ADF

Swap one canvas for another

Heavier UI, slower debugging
Still a canvas as the unit of reuse
Awkward for lookup-heavy SSIS work
Integration Runtime is a holding pattern
Does not fix Git, tests, or maintainability

Why AI actually helps here

A .dtsx package is a designer canvas serialized as XML. AI is weak at that. It is strong at C#. Once the flow is code, you can ask a model to draft a lookup, add a test, or review a PR — and you can still compile the result. That is the practical reason a code-first migration moves faster than redrawing the same package in ADF: the work is text a model can hold on to.

This is not an automated .dtsx importer. You rewrite the package in C# with the same components. AI is useful because that rewrite is code, not because a wizard hides the designer.

SSIS toolbox → ETLBox

The components production packages actually spend time in. Not every SSIS item (Fuzzy Lookup, DQS, the SCD wizard) has a one-click twin.

SSIS	ETLBox
Execute SQL / Truncate Table	`SqlTask`, `TruncateTableTask`
Flat File Source	`CsvSource`
Derived Column / Script Component	`RowTransformation`
Lookup	`LookupTransformation`
Conditional Split	`LinkTo(..., predicate)` or `ConditionalSplit`
OLE DB Destination	`DbDestination`
Error output	a second `LinkTo` predicate, or `LinkErrorTo`
ForEach File	a C# `foreach` over files, or `HasNextUri` on a source
Aggregate / Sort / Pivot / Merge Join / Multicast	`Aggregation`, `Sort`, `Pivot`, `MergeJoin`, `Multicast`

A full Control Flow and Data Flow — partner CSV, customer lookup, range lookup the SSIS Lookup transform cannot do, staging merge, error file — is in the walkthrough: Replacing SSIS with a C# data flow.

Used in production — not as a weekend project

Commonwealth Bank of Australia, Deloitte, Health Catalyst, SEW Eurodrive, Calpine, FASTEC. Teams run ETLBox because a nightly load has to survive the next decade of package changes, not the next designer.

Evaluate the code-first path

Keep the engine. Drop the canvas.

A trial key unlocks the full library. NuGet without a key is limited to 5,000 rows per data flow. If you want the packages rewritten with you, the people who built ETLBox take that work.

Get a free trial key Read the walkthrough Need us to migrate it?