Do I need to install anything?

No. It runs in any modern browser, free, with no account required.

For Engineers · Project Portfolio

Project Portfolio for an externality

Built for engineers using it for real design work. Go from concept to a running model in the browser, then scale to the cloud when needed. Simulate an externality live below — adjust the inputs and watch it respond, right in your browser.

Critical Path

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Critical Path MethodLive

project scheduling

Controls

Presets

Task B duration (days)

Task D duration (days)

The Critical Path Method finds the longest chain of dependent tasks through a project — the sequence that sets the minimum completion time. Tasks on it have zero slack: delay any one and the whole project slips. Tasks off it can float. Stretch task B or D and watch the critical path re-route. The backbone of project management.

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Data Inspector

Project duration15 days

Critical tasksA, B, D, F

Tasks6

Reading this result: The critical path is A → B → D → F at 15 days. Tasks C, E carry slack — delaying them will not move the finish date, but any slip on a critical task pushes the whole project.

Governing equation

T = paths max i \sum d_{i} = 15 days, slack_{i} = L S_{i} - E S_{i}

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Monte Carlo

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Monte Carlo Price SimulationLive

geometric Brownian motion

Controls

Presets

Initial price S₀

Expected return μ

Volatility σ

Horizon (years)

Geometric Brownian motion models a price with constant drift and random volatility — the assumption behind Black-Scholes. Running hundreds of simulated paths reveals the full distribution of outcomes, not just an average. Educational tool, not investment advice.

▶ Run in Python

Data Inspector

Median outcome$0

5th percentile$0

95th percentile$0

Governing equation

S_{t + Δ t} = S_{t} e^{(0.07 - \frac{0. 2 ^{2}}{2}) Δ t + 0.2 Δ t Z}, \tilde{S}_{1} \approx $0

Reading this result: Median outcome is about $0, just under the drift-only $107 — GBM compounds in log-space, so volatility always pulls the typical path below the average.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Frequently asked questions

Is this good for engineers?: Yes — this version of "Project Portfolio for an externality" is framed for engineers using it for real design work. Go from concept to a running model in the browser, then scale to the cloud when needed.
Do I need to install anything?: No. It runs in any modern browser, free, with no account required.