Critical-path scheduling
Most of your schedule cannot move the end date. This is the part that can.
Every plan has one chain of work that sets the finish. Everything else has float and can slip without costing you a day. LumaPlan keeps that chain lit, so you always know which delay is the one that matters.
A real forward and backward pass, running here. Click any bar to push it two days and watch what happens to the finish.
Why it matters
A late task is not the same as a late project.
On a schedule of any size, most activities carry float. They can start late, run long, or sit idle for a week, and the completion date does not move. Chasing them costs you attention and buys nothing.
The driving path is the chain where float has run out. Push any task on it and the finish date moves the same day, by the same amount. That is the only work worth escalating, and on a thousand-line programme it is not obvious which work it is.
LumaPlan computes it on every change and shows it directly on the bars — not buried in a filter you have to remember to apply.
Interchange
It reads the schedules you already have.
Your programme lives in someone else's file, and the people you report to are not going to change tools. LumaPlan opens their formats directly and writes them back, so it fits into the chain you already work in.
- MS Project
- .mpp read directly — the binary format, parsed natively. .mspdi / .xml read and write.
- Primavera
- .xer and .pmxml read and write, checked against P6 exports task by task.
- Exchange
- .mpx, plus a native .lplan file that round-trips everything the other formats drop.
- No runtime
- Every reader is pure Rust. One binary, nothing to install alongside it and no companion service to keep running.
- Out
- PDF submittals, timescaled Gantt, XLSX, PowerPoint and a 16:9 presentation view.
- Conventions
- Switches between MS Project and P6 date arithmetic, because the two disagree and your dates should match whoever you are reporting to.
Scale
Built against a real programme, not a demo file.
Performance targets are held to a live construction schedule rather than a synthetic one, and they are regression-tested — because a scheduler that stutters at ten thousand lines is a scheduler you stop opening.
Platforms
The same schedule, wherever you open it.
Web
Installs as a desktop app from the browser and keeps working offline. Multiple people on one schedule, with live presence.
macOS & Windows
A real native build, not a wrapped tab. Opens local files directly and signs in as you.
Tablet
Laid out for a site tablet — progress, lookahead and the driving path, without a mouse.
Know which delay actually costs you.
LumaPlan is in active development. It is being built against real construction programmes, and it is not open for signups yet.