GridCraft is an open-source desktop spreadsheet application, a clean-room rebuild of the Microsoft Excel workflow written in pure Rust by the ArtCraft team. It is aimed at people who live in spreadsheets but would rather not rent one: analysts, finance and operations staff who need XLSX files to open correctly, plus developers who want a grid their scripts and AI agents can drive. It is also very new. The repository was created on 7 October 2026 and last pushed on 17 October 2026, and it has already gathered more than 5,500 stars and 2,500 forks, so read it as an early project with a lot of attention rather than a settled product.
What it does
GridCraft opens and saves the same XLSX files Excel does, according to the project, so trading workbooks with colleagues is the design target rather than an afterthought. The interface is a ribbon holding the parts a spreadsheet user reaches for first:
- a formula bar
- pivot tables
- more than 500 functions (the project's own count)
- dynamic arrays
- charts, sparklines, data bars and a totals row
The project ships a built-in sample workbook that was itself assembled with GridCraft's own commands, and the video shows that sample with charts, sparklines, a totals row and pivot tables all live rather than as screenshots. The sample doubles as the honest demo: what works there is what the authors are claiming.
"Clean room" here means the authors say they wrote the whole thing without touching Excel's code. File compatibility comes from reading and writing the format, not from reusing Microsoft's implementation.
How it works
The application is Rust end to end. The README says it runs natively on macOS, Windows, Linux and BSD, and in the browser through WebAssembly, which is the usual payoff of a single Rust core with no runtime underneath it. The speed claims in the README are the authors' own description, not an independent benchmark, and the materials contain no measured numbers at all.
The more unusual half is the command layer. Every button in the ribbon is also a command, and the project advertises those commands as drivable by an AI agent over MCP (Model Context Protocol). That is the same command surface the bundled sample was built from, which is a reasonable sign the automation path is real and not a thin wrapper added later. Note what this does not mean: GridCraft ships no model and sends your sheet nowhere by itself. The intelligence is whatever agent you point at it.
Getting started
The code is at github.com/storytold/gridcraft. The project names its platforms (macOS, Windows, Linux, BSD, and the web through WebAssembly) but does not list hardware requirements, so do not assume anything about memory or chip beyond "a normal desktop machine". The copy of the README saved for this entry is cut off before any install or build section, so this page cannot give you the exact build command or confirm whether prebuilt binaries are published under Releases: check the repository and the project's page at getartcraft.com/apps/gridcraft. Building from source will need a Rust toolchain. Licensing is permissive either way: GitHub reports Apache-2.0, while the README badge offers MIT or Apache-2.0. There is a Discord community linked from the README.
On money: GridCraft is free software that runs on your own machine, and nothing in the materials requires a paid service to use the spreadsheet, so the "no subscription" line in the video holds for the app itself. The one place cost can enter is automation. If you want the MCP commands driven by a model, you pay for that model yourself, either by running a local one on your hardware or by connecting a paid API key.
When to use it / when not
The main catch is stated plainly by the channel: open an old .xls file and the formatting does not come along yet. The second catch is age. A spreadsheet is judged on edge cases, and a project ten days old has no track record on large workbooks, odd number formats or long recalculation chains. The materials also say nothing about VBA macros or Excel add-ins, so assume those are absent until the repository says otherwise.
Use it instead of Microsoft Excel when you want a local, no-subscription grid that still exchanges XLSX, or when you want a spreadsheet an agent can operate command by command instead of through brittle screen control. Don't use it if your work depends on inherited .xls files keeping their formatting, on macros, or on a spreadsheet that has been debugged for years.
Anyone who files spreadsheet work under "tools I should not have to rent" should watch this repository, and anyone building agents that produce reports has a stronger reason still: a scriptable, local grid with a declared command surface is a better target than automating a closed office suite. Just treat the current state as a promising first release, keep the originals of anything important, and verify the files it writes before you send them to someone whose only reader is Excel.