---
title: "Build with the vendor compiler"
---

# Build with the vendor compiler

Build and rebuild TwinCAT, CODESYS and TIA Portal projects through the vendor engine by command, task or agent, with the compiler's messages in Problems.

The Editor never compiles IEC 61131-3 code itself. Builds go through the [engineering host](https://neuralinverse.com/docs/modules/plc/toolchain/) to the vendor compiler you already use: the TwinCAT Automation Interface, the CODESYS scripting engine and TIA Portal Openness.

**State:** kit shipped for TwinCAT, CODESYS and TIA Portal. The commands, tasks, status bar and Problems markers are tested on Linux against a model of the engineering host, and the real engineering host is tested on Linux, where no engine exists. **No vendor compiler has run.** The message formats parsed are the documented ones, not yet captured from a real build.

## Build a project

Command Palette, category Neural Inverse PLC:

| Command | What it does |
|---|---|
| Build Project | Builds the project in its resident engine session |
| Rebuild Project | Rebuilds. A TIA Portal project is listed with the reason it cannot be rebuilt (Openness documents only a compile), and picking it builds nothing |
| Cancel Build | Cancels the running build |

Build Project and Cancel Build are also buttons on the **TwinCAT Projects** view. With several projects, the command asks which.

## Build tasks

Terminal > Run Task offers, with source "PLC" and type `ni-plc-build`:

- a Build and a Rebuild task per TwinCAT project (`.tsproj`);
- a Build and a Rebuild task per CODESYS project (`name.project`);
- a Build task per TIA Portal project (`.apNN`).

With one project in the workspace, its build is the default build task.

## While it builds and after

- The status bar entry **PLC Build** shows "Building ..." while a build runs; click it to cancel.
- The compiler's messages go to Problems, named after the engine, for example `TwinCAT 3.1.4024.60 build`, `CODESYS 3.5.19.50 build` or `TIA Portal V19 build`.
- The **PLC** output channel has the build's log.

| Vendor | Engine used | Where messages land |
|---|---|---|
| TwinCAT | The TwinCAT version the `.tsproj` pins. A project whose pinned version is not installed is not opened in another one, and the message names what was found | At the object file and line |
| CODESYS | The CODESYS of `neuralInverse.plc.paths.codesys`, with the profile of `neuralInverse.plc.codesys.profile`. Without the setting, the build says so and starts nothing | On the `.project` file at line 1, naming the object (`... (reported at PLC_PRG)`) |
| TIA Portal | TIA Portal V`NN`, the version of the `.apNN` extension, never a newer one (which would upgrade the project) | On the `.apNN` file at line 1, naming the object path (`... (reported at PLC_1/Program blocks/Main [OB1])`) |

A build in the same session opens the project again when it changed on disk and never saves it. One resident engine session per project serves its builds, and its controller actions, one after the other.

Agents can build too: the tools **Build PLC Project** and **Rebuild PLC Project** are asked every time (see [Agent tools](https://neuralinverse.com/docs/modules/plc/agents/)).

## Project files the engineering host opens

The engineering host opens a CODESYS `.project` and a TIA Portal `.apNN` only, not archives or text-based project folders. See [What's next](https://neuralinverse.com/docs/modules/plc/whats-next/).

## Not verified

- Any build by TwinCAT, CODESYS or TIA Portal.
- Placing CODESYS and TIA Portal messages at a line.
- Build times on a project of realistic size.