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A data-oriented shell

Filesystem Data as Tables

The ls command in Nushell returns a table of files with columns such as name, type, size, and modified timestamp, rather than a simple text listing. This means you can query it directly. For example, you can list directories in the current folder sorted by last modified time (as shown in Figure 3) with

ls | where type == "dir" | sort-by modified | reverse

Figure 3: The ls command filters and sorts only directories by their last modified time, displaying the results in a structured table with color-coded columns for clarity.

System Information as Structured Data

Commands such as ps (process list) and sys (system info) are built into Nushell and return structured data as well. For instance, ps gives you a table of running processes (with columns for PID, name, CPU, memory, etc.). You could find the top memory-consuming process (see Figure 4) with

ps | sort-by mem | last 1

Figure 4: Nushell displays the process using the most memory (in this case, dockerd) with detailed metrics in a structured table format.

Opening and Parsing Structured Files

Nushell's open command is a powerful way to bring data from files (or URLs) into Nushell's pipeline. It auto-detects file types including JSON, CSV, TOML, YAML, XML, Excel, SQLite, and more and parses them into tables or records [2]. For example, the table in Figure 5 is generated with

open stack.yaml

Figure 5: Nushell opens and visualizes the stack.yaml file as a nested table, making it easy to inspect OpenFaaS deployment details such as provider, gateway URL, and function configuration.

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