What is J written in?

The J runtime is written in C.

J is a programming language, first released in 1990.

Implementation

LayerWritten inNotes
RuntimeC (since 1990)J interpreter written in C by Ken Iverson and Roger Hui

Runtime model

The J runtime, written in C, manages the execution of J programs. Runtime-based languages rely on a host process to interpret or compile code at runtime rather than compiling entirely ahead-of-time to native machine code. This means running J programs requires the runtime to be present on the target system.

The choice of C for the runtime gives J access to native performance, established platform abstractions, and existing ecosystem libraries.

Explore in the Graph

See J's full lineage, including all implementation and influence relationships, in the interactive graph.

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Or view the J language page for the complete record.

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