Benchmarks¶

Rezi includes a benchmark suite comparing terminal UI pipelines across 22 scenarios. The authoritative write-up, methodology, and raw artifacts live in:

BENCHMARKS.md — full scenario definitions, results, and caveats
benchmarks/ — committed JSON + Markdown result sets

Frameworks¶

Framework	Runtime	Notes
Rezi	Node.js	Full layout engine, binary drawlist, native C renderer
Ink	Node.js	React reconciler + Yoga layout + ANSI string output
OpenTUI (React)	Bun	React declarative driver on `@opentui/core`
OpenTUI (Core)	Bun	Direct imperative API, no React overhead
Bubble Tea	Go binary	Elm architecture, `lipgloss` string rendering
terminal-kit	Node.js	Low-level terminal buffer, no layout system
blessed	Node.js	Imperative terminal UI, no constraint layout
Ratatui	Rust binary	Native immediate-mode renderer

Selected results — 2026-02-27, M4 Pro, PTY mode¶

Single-replicate quick run. Numbers are directional; see BENCHMARKS.md for caveats.

Primitive workloads¶

rerender — one value changes in a stable tree:

Framework	Mean	ops/s
terminal-kit	60µs	16,400
Ratatui	70µs	14,300
blessed	71µs	14,000
Rezi	391µs	2,600
OpenTUI (Core)	1.18ms	850
OpenTUI (React)	2.72ms	368
Bubble Tea	8.32ms	120
Ink	20.03ms	50

tree-construction — build a widget tree from scratch:

Framework	100 items	1000 items
Rezi	209µs	1.55ms
terminal-kit	203µs	1.91ms
Ratatui	917µs	2.37ms
OpenTUI (Core)	1.59ms	17.60ms
blessed	1.82ms	19.73ms
Ink	24.61ms	78.94ms
OpenTUI (React)	10.67ms	102.49ms

Full-app workloads (PTY output)¶

terminal-full-ui — composite dashboard, 24 services, 40×120 terminal:

Framework	Mean	ops/s	Peak RSS
Ratatui	267µs	3,700	2.8 MB
blessed	331µs	3,000	100 MB
Rezi	1.24ms	806	89 MB
OpenTUI (Core)	1.31ms	765	107 MB
OpenTUI (React)	3.15ms	317	162 MB
Bubble Tea	8.33ms	120	~2 MB
Ink	22.09ms	45	170 MB

terminal-strict-ui — structured multi-panel layout (header, 3-column body, footer, status bar):

Framework	Mean	ops/s
Ratatui	189µs	5,300
blessed	334µs	3,000
Rezi	950µs	1,100
OpenTUI (Core)	1.27ms	788
OpenTUI (React)	4.60ms	217
Bubble Tea	8.32ms	120
Ink	22.41ms	45

terminal-virtual-list — 100K items, 40-row viewport, full PTY output:

Framework	Mean	ops/s
Ratatui	129µs	7,700
blessed	154µs	6,500
Rezi	798µs	1,300
OpenTUI (Core)	1.09ms	916
OpenTUI (React)	6.75ms	148
Bubble Tea	8.32ms	120
Ink	22.56ms	44

Memory¶

Peak RSS at terminal-level workloads:

Framework	Typical range
Ratatui	2–3 MB
Bubble Tea	1–30 MB
Rezi	83–215 MB
terminal-kit	83–142 MB
blessed	85–420 MB
OpenTUI (Core)	85–243 MB
Ink	128–1,250 MB
OpenTUI (React)	96–5,440 MB

Running benchmarks¶

Prerequisites¶

# Build Rezi
npm ci && npm run build && npm run build:native
npx tsc -b packages/bench

# Bun — required for OpenTUI scenarios
# Install: curl -fsSL https://bun.sh/install | bash

# Go — required for Bubble Tea (built automatically on first run)

# Rust/cargo — required for Ratatui (must be built manually):
cd benchmarks/native/ratatui-bench && cargo build --release && cd -

Quick run — all frameworks, PTY mode¶

PATH="$HOME/.cargo/bin:$HOME/.bun/bin:$PATH" \
REZI_BUN_BIN="$HOME/.bun/bin/bun" \
node --expose-gc packages/bench/dist/run.js \
  --suite all --io pty --quick \
  --output-dir benchmarks/local-all

Full run (more iterations)¶

PATH="$HOME/.cargo/bin:$HOME/.bun/bin:$PATH" \
REZI_BUN_BIN="$HOME/.bun/bin/bun" \
node --expose-gc packages/bench/dist/run.js \
  --suite all --io pty \
  --output-dir benchmarks/local-full

Rigorous terminal suite — multi-replicate, shuffled¶

Suitable for publication-grade comparisons. Requires bare-metal Linux with CPU pinning for minimal jitter:

node --expose-gc packages/bench/dist/run.js \
  --suite terminal --io pty \
  --replicates 7 --discard-first-replicate \
  --shuffle-framework-order --shuffle-seed my-run \
  --cpu-affinity 0-7 --env-check warn \
  --output-dir benchmarks/local-terminal

Targeted runs¶

# One scenario across all frameworks
node --expose-gc packages/bench/dist/run.js \
  --scenario terminal-full-ui --io pty --quick

# One framework across all scenarios
node --expose-gc packages/bench/dist/run.js \
  --framework rezi-native --io pty --quick

# Rezi vs OpenTUI Core
node --expose-gc packages/bench/dist/run.js \
  --matchup rezi-opentui --opentui-driver core \
  --io pty --quick --output-dir benchmarks/local-matchup

Key flags¶

Flag	Description
`--suite all\\|terminal`	All scenarios, or terminal-only
`--framework <name>`	Single framework
`--scenario <name>`	Single scenario
`--io stub\\|pty`	Stub (no PTY) or real terminal write
`--quick`	Reduced iteration counts for fast checks
`--replicates <n>`	Repeat the full run N times
`--output-dir <path>`	Write `results.json` + `results.md`

See BENCHMARKS.md for the full scenario reference, methodology notes, and interpretation guidance.