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Dev tools · September 7, 2021

ST

Symbolica – Try our symbolic code executor in the browser

We're a couple of software engineers who believe that to build great software you need to write good tests, but we also sympathise when engineers say things like: - "Writing tests was too time consuming on my tight schedule", or - "Unit tests don't catch enough bugs, so they're useless", or - "I've inherited a legacy code base without tests and have no idea where to start" To tackle this we're building Symbolica (https://www.symbolica.dev), a symbolic code executor [1], that lets you run your code for all possible inputs. This means you can do things like: - Assert properties about…

Symbolica – Try our symbolic code executor in the browser launched on September 7, 2021 with 45 votes, #1,084 of 2,941 launches that month and more than 75% of that year's launches.

Alternatives

In plain words

Symbolica is a browser-based symbolic code executor that runs code across all possible inputs simultaneously. It allows developers to verify code properties hold for every conceivable input, check if different implementations are equivalent, and detect undefined behaviors. The tool targets engineers who struggle with time-consuming test writing, find traditional unit tests insufficient, or need to work with untested legacy code.

written from the facts on this page · September 2026

From the sources

In the maker’s words, at launch

We're a couple of software engineers who believe that to build great software you need to write good tests, but we also sympathise when engineers say things like: - "Writing tests was too time consuming on my tight schedule", or - "Unit tests don't catch enough bugs, so they're useless", or - "I've inherited a legacy…

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Source: Show HN post ↗ · launch text quoted in part

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