oha

oha is an HTTP load-testing CLI for generating concurrent traffic against a URL or a file of URLs and summarizing how the server responded. It covers quick benchmark runs, rate-limited load checks, and live terminal monitoring.

• Benchmark APIs or sites with fixed request counts or timed runs, tuning concurrency, QPS, burst behavior, keep-alive, HTTP version, headers, auth, and request bodies.
• Measure latency percentiles, histograms, first-byte timing, throughput, and status-code distribution, then export summaries as JSON or per-request data as CSV.
• Replay more realistic traffic mixes with URL lists or generated URL patterns, and optionally persist successful request records to SQLite for later analysis.

• Non-interactive flags, --no-tui, and structured JSON or CSV output make it easy to slot into CI checks, performance regressions, and agent verify loops.
• The default ratatui monitor is a real fullscreen TUI for humans watching a run, but the code uses a faster collection path when TUI is disabled, which is the better automation mode.
• Fit is strongest for inspect-only HTTP performance checks; it does not model browser execution or richer multi-step user journeys.

• --output-format json produces a summary document rather than per-request event records; use CSV or the SQLite sink when each request matters.
• It operates at the raw HTTP request layer, so JavaScript execution, rendering, and browser-managed session behavior are outside scope.