Google Sheets Live Bridge

Overview

The Veydra Live Bridge is a Google Workspace Add-on that connects Google Sheets directly to the Veydra System Dynamics Engine. It replaces static file exports with real-time, bi-directional sync — giving you native spreadsheet recalculation with sub-200ms latency.

Unlike legacy tools that require exporting files and manually importing data, the Live Bridge maintains a persistent connection to your Veydra models with automatic updates.

Key Benefits

Real-Time Sync

Changes in Sheets instantly update your Veydra model, and simulation results flow back automatically

Native Experience

Works with familiar spreadsheet features — formulas, ranges, and dynamic arrays

Multi-User Collaboration

Multiple users can work on the same sheet with real-time updates across all sessions

Live Model Info

Generate auto-updating sheets with all model variables, units, and current values

How It Works

+----------------------------------------------+
|                Google Sheet                   |
|                                               |
|  +-------------+   +----------------------+  |
|  |  Sidebar UI |   |  =VEYDRA.FORECAST()  |  |
|  |  (Controls) |   |  Custom Functions    |  |
|  +------+------+   +----------+-----------+  |
|         |                     |              |
|  +------+---------------------+------------+ |
|  |         Apps Script Host Layer          | |
|  +--------------------+--------------------+ |
+------------------------|---------------------+
                         |  REST + WebSocket
                         v
           +------------------------+
           |   Veydra Cloud Engine  |
           +------------------------+

The Live Bridge consists of:

Sidebar UI — A React-based panel for authentication, model selection, and parameter controls
Custom Functions — Spreadsheet formulas like =VEYDRA.FORECAST() that fetch simulation results
Apps Script Layer — Handles triggers, sheet I/O, and the WebSocket connection to Veydra

Features

Bi-Directional Cell Mapping

Map spreadsheet cells directly to Veydra model nodes: Sheet → Veydra (Inputs)

Select a cell range in your spreadsheet
Open the Veydra sidebar and click Bind
Choose the input node to map (e.g., “Marketing Spend”)
Changes to those cells automatically update the model

Veydra → Sheet (Outputs) Use the VEYDRA.FORECAST function to pull simulation results:

=VEYDRA.FORECAST("model_id", "input_range", "output_node")

This function supports Dynamic Arrays — a 12-month forecast automatically populates 12 cells without needing to copy the formula down.

Reactive Sliders

The sidebar includes interactive sliders for model parameters:

Drag a slider to change a parameter value
The Veydra engine recalculates immediately
Results update in your spreadsheet in real-time (no manual refresh)

This is perfect for sensitivity analysis and exploring “what-if” scenarios.

Model Info Generator

Generate a comprehensive summary sheet of your connected model:

Open the sidebar and click Generate Model Info Sheet
A new sheet is created with all variables, their units, and current values
Unlike static exports, this sheet stays synchronized with your model

Multi-User Real-Time Sync

When multiple users have the same Google Sheet open:

User A changes a parameter via the sidebar
User B sees the updated values appear in their sheet automatically
Both users see the same simulation results

This enables collaborative scenario planning and teaching sessions.

Getting Started

Installation

Open Google Sheets

Create a new spreadsheet or open an existing one at sheets.google.com

Install the Add-on

Go to Extensions → Add-ons → Get add-ons and search for “Veydra Live Bridge”Click Install and grant the required permissions

Open the Sidebar

After installation, go to Extensions → Veydra Live-Bridge → Open Sidebar

Click Sign in with Google in the sidebar to authenticate with your Veydra account

Connecting a Model

Select a Model

In the sidebar, use the Model dropdown to select from your available Veydra models

View Model Details

Click Generate Model Info Sheet to see all available variables and their current values

Bind Input Cells

Select cells in your sheet, then click Bind in the sidebar to map them to model inputs

Add Output Formulas

Enter =VEYDRA.FORECAST() formulas to display simulation results

Custom Functions Reference

VEYDRA.FORECAST

Runs a simulation and returns the forecast values for an output variable.

=VEYDRA.FORECAST(model_id, input_range, output_node, [periods])

Parameter	Type	Description
`model_id`	String	The Veydra model ID (found in the model URL)
`input_range`	Range	Cell range containing input values
`output_node`	String	Name of the output variable to return
`periods`	Number	(Optional) Number of time periods to forecast

Example:

=VEYDRA.FORECAST("12345", B2:B13, "Revenue", 12)

Returns a 12-row array of forecasted revenue values based on the inputs in B2:B13.

Comparison with Legacy Tools

Feature	Stella/Vensim (Legacy)	Veydra Live Bridge
Data sync	Static .sem file exports	Live WebSocket connection
Update latency	Manual re-import	Under 200ms automatic
Collaboration	Single-user file ownership	Multi-user real-time sync
Info sheets	Static snapshot	Live-updated
Dynamic arrays	Not supported	Native support
Version control	Manual file copies	Cloud-based with history

Troubleshooting

Sidebar won't open

Ensure you’ve granted the add-on the required permissions
Try refreshing the page and reopening via Extensions → Veydra Live-Bridge → Open Sidebar
Check that pop-ups are not blocked for Google Sheets

VEYDRA.FORECAST returns an error

Verify the model ID is correct (check the URL in app.veydra.io)
Ensure the output node name matches exactly (case-sensitive)
Check that your input range contains valid numeric values

Changes not syncing in real-time

Check your internet connection
The WebSocket connection may have timed out — close and reopen the sidebar
Verify the Veydra service is operational at status.veydra.io

Requirements

Google account with access to Google Sheets
Veydra account with at least one model
Modern browser (Chrome, Firefox, Edge, or Safari)
Internet connection for real-time sync

Getting Started

Platform Features

Model Playground

Simulation Components

Tools

Integrations

Development

Overview

Key Benefits

Real-Time Sync

Native Experience

Multi-User Collaboration

Live Model Info

How It Works

Features

Bi-Directional Cell Mapping

Reactive Sliders

Model Info Generator

Multi-User Real-Time Sync

Getting Started

Installation

Connecting a Model

Custom Functions Reference

VEYDRA.FORECAST

Comparison with Legacy Tools

Troubleshooting

Requirements

​Overview

​Key Benefits

Real-Time Sync

Native Experience

Multi-User Collaboration

Live Model Info

​How It Works

​Features

​Bi-Directional Cell Mapping

​Reactive Sliders

​Model Info Generator

​Multi-User Real-Time Sync

​Getting Started

​Installation

​Connecting a Model

​Custom Functions Reference

​VEYDRA.FORECAST

​Comparison with Legacy Tools

​Troubleshooting

​Requirements

Overview

Key Benefits

How It Works

Features

Bi-Directional Cell Mapping

Reactive Sliders

Model Info Generator

Multi-User Real-Time Sync

Getting Started

Installation

Connecting a Model

Custom Functions Reference

VEYDRA.FORECAST

Comparison with Legacy Tools

Troubleshooting

Requirements