I built a TUI for testing regex patterns without leaving the terminal. It's most useful if you're working over SSH, in containers, or just prefer not to context-switch to regex101.com.
What it does:
- Live matching that updates on every keystroke
- 3 regex engines (Rust regex, fancy-regex, PCRE2) — switch with Ctrl+E to compare behavior differences
- Capture group highlighting with distinct colors per group
- Plain-English explanations generated from the regex AST
- Replace/substitution mode with live preview
- Pipe from stdin: echo "log line" | rgx '\d+' and output results to stdout with Ctrl+O
- Written in Rust with ratatui. Install: cargo install rgx-cli or brew install brevity1swos/tap/rgx.
To be clear about what this isn't: regex101.com is more capable overall — more engines, step-through debugging, shareable links, community patterns. rgx doesn't try to replace it.
Where rgx fills a gap: testing patterns on remote servers where you can't open a browser, piping results into other commands, and testing against the actual Rust regex crate behavior (which regex101 doesn't support).
The multi-engine switching is the feature I use most — instantly checking if a lookahead works in Rust's regex crate vs PCRE2.
Would love feedback on what would actually be useful for your workflow.
I built a TUI for testing regex patterns without leaving the terminal. It's most useful if you're working over SSH, in containers, or just prefer not to context-switch to regex101.com.
What it does:
- Live matching that updates on every keystroke - 3 regex engines (Rust regex, fancy-regex, PCRE2) — switch with Ctrl+E to compare behavior differences - Capture group highlighting with distinct colors per group - Plain-English explanations generated from the regex AST - Replace/substitution mode with live preview - Pipe from stdin: echo "log line" | rgx '\d+' and output results to stdout with Ctrl+O - Written in Rust with ratatui. Install: cargo install rgx-cli or brew install brevity1swos/tap/rgx.
To be clear about what this isn't: regex101.com is more capable overall — more engines, step-through debugging, shareable links, community patterns. rgx doesn't try to replace it.
Where rgx fills a gap: testing patterns on remote servers where you can't open a browser, piping results into other commands, and testing against the actual Rust regex crate behavior (which regex101 doesn't support).
The multi-engine switching is the feature I use most — instantly checking if a lookahead works in Rust's regex crate vs PCRE2.
Would love feedback on what would actually be useful for your workflow.