Pulsar: Redefining the Pharo IDE at ESUG 2026

By Esteban Lorenzano | September 7, 2026 | ⏱️ 1 min read

At the ESUG 2026 conference in Plovdiv, I had the opportunity to introduce Pulsar, a fresh, coding-centric Integrated Development Environment (IDE) specifically designed for Pharo.

The Philosophy of "Coding-First"

In an era where ~~manual coding~~ is often overshadowed by the rebirth of Rapid Application Development (RAD) via generative AI agents, one might wonder if a "coding-first" approach is still relevant.

"Programming tools should empower developers to deeply understand, navigate, and modify their systems while remaining intimately connected to the source code."

While generative tools are powerful, they do not replace the necessity of these core capabilities. The goal of Pulsar is to cultivate the "power user" within every developer.

The Power User Equation

We can think of the growth of a developer's capability as: $\text{Capability} = \int (\text{Tooling Efficiency} \times \text{Code Proximity}) \, dt$

Key Technical Advancements

Pulsar isn't just a shell; it introduces significant functional improvements to the Pharo ecosystem.

1. Modern String Interpolation (F-Strings)

F-strings are making their way into Pharo. Pulsar currently implements a version that provides:

Readable interpolation for cleaner code.
Full AST (Abstract Syntax Tree) support.
Seamless debugger integration.
Backward compatibility as a bridge toward Pharo 15.

Example Concept:

"Hypothetical F-String usage in Pulsar"
f"The current system time is {Date today}"

2. Scalable Version Control Visualization

Pulsar integrates a new "Git river" based on git-rivera. Unlike traditional graphs that can lag with massive histories, this implementation generates commit graphs lazily and on-demand.

Feature	Traditional Git Browsers	Pulsar (Git Rivera)
Loading	Eager / Full Load	Lazy / On-Demand
Scalability	Struggles with large repos	High scalability
Performance	Potential UI freeze	Fluid navigation

Current Status & Community Call

Pulsar is currently in pre-alpha, though it recently achieved a milestone by winning first prize at ESUG 2026. It is designed for real-world working sessions and is ready for those who enjoy the "bleeding edge."

How you can contribute:

Download the IDE from the Smallworks Forge.
Use it in your daily Pharo workflow.
Attempt to break the system.
Send feedback to help shape the future of the tool.

Resources:

Presentation Slides: Pulsar: A New Pharo IDE — Growing the Power User in You
Source Code: https://forge.smallworks.eu/pharo/Pulsar