lazycsv

A blazingly fast terminal UI for CSV files. Navigate huge datasets with vim keys, switch between files instantly, and never touch your mouse.

Inspired by lazygit, lazydocker, and lazysql.

 lazycsv: sales_data.csv                                              2/100
──────────────────────────────────────────────────────────────────────────
      A           B              C              D           E
  #   ID          Date           Product        Qty         Price
  1   001         2024-01-15     Widget A       100         $25.00
> 2   002         2024-01-16     Gadget B       50          $42.50
  3   003         2024-01-17     Doohickey      75          $18.75
  4   004         2024-01-18     Thingamajig    200         $12.00
  5   005         2024-01-19     Whatchamacal   150         $35.00
──────────────────────────────────────────────────────────────────────────
sales.csv | customers.csv | orders.csv                               [1/3]
NORMAL                                                    2,B "2024-01-16"

Why LazyCSV?

• Fast - 100K+ rows at 60 FPS (in-memory)
• Vim keys - hjkl your way through data, full vim emulation planned
• Multi-file - switch between CSVs like Excel sheets (press [ ])
• Simple - no config needed, just works
• Clean - minimal vim-like UI, zero clutter

Note: LazyCSV loads the entire CSV file into memory for maximum performance. This design choice prioritizes speed and simplicity over handling files larger than available RAM.

Install

git clone https://github.com/funkybooboo/lazycsv.git
cd lazycsv
cargo install --path .

Quick Start

# Open current directory (scans for CSV files)
lazycsv

# Open specific file
lazycsv data.csv

# Open a directory
lazycsv ./data/

# With options
lazycsv data.csv --delimiter ';' --no-headers

# In the app:
# hjkl or arrows  -> navigate
# [ or ]          -> switch between CSV files
# gg or G         -> jump to top/bottom
# :B or :A5       -> jump to column B or cell A5
# ?               -> show help
# :q              -> quit

That's it! Press ? in the app for full keybindings.

Essential Keys

Key	Action
hjkl or arrows	Move around (with count: 5j, 10h)
gg / G / 15G	Jump to first/last/line 15
:B / :A5	Jump to column B or cell A5
w / b / e	Next/prev/last non-empty cell
:15	Command mode: jump to row 15
zt / zz / zb	Position row at top/center/bottom
[ / ]	Switch CSV files
?	Show help
:q or q	Quit

Vim users: All your favorite motions work (0, $, count prefixes, etc.)

Innovation: Multi-File Navigation

LazyCSV treats CSV files in the same directory like Excel sheets. Open one file, instantly switch between all of them with [ and ] keys. No more cd and reopening!

Roadmap to v1.0

Version	Features
v0.1.0	Foundation - viewing, navigation, multi-file
v0.2.0	Type safety refactor (internal)
v0.3.0	Advanced navigation - column jumps, command mode, word motion
v0.3.1	UI/UX polish - mode indicator, transient messages, help redesign
v0.3.2	Pre-edit polish - minimal UI, vim-like status line
v0.4.0	Insert mode - quick cell editing, row operations
v0.4.1	Persistence - :w, :W, multi-file dirty tracking, command ranges
v0.5.0	Column operations - ;o, ;O, ;dd, ;yy, ;p, visual mode
v0.6.0	Vim Magnifier - multi-line cell editing with full vim
v0.7.0	Search - /, n, N fuzzy cell search
v0.8.0	Undo/redo - u, Ctrl+r, . dot command
v0.9.0	Transforms - :sort, :filter, data operations
v1.0.0	Stable release - polish, performance, docs

Post-v1.0 Features

Future considerations (not committed):

• Column resize & freeze
• Advanced features - macros, tab completion
• Data export - JSON, Markdown, HTML

See plans/roadmap.md for the complete detailed roadmap.

Documentation

• Keybindings - Every keyboard shortcut by version
• Design - How it looks and feels
• Architecture - How it works
• Development - How to contribute

Development

# Using Task (recommended)
task run        # run with sample.csv
task test       # run tests
task all        # format, lint, test

# Or with Cargo
cargo run -- sample.csv
cargo test

See docs/development.md for contributing guidelines.

Status

v0.4.0 Complete! Fast CSV editing with vim keys. Insert mode for cell editing, row operations, and full keyboard control.

• Fast CSV viewer and editor with vim navigation
• Multi-file switching with [ ]
• Row/column numbering (A, B, C...)
• Column jumping with :B syntax (:B, :AA, :A5)
• Command mode with reserved commands (:q, :w, :h)
• Word motion (w/b/e for sparse data)
• Viewport control (zt/zz/zb)
• Minimal vim-like UI (no heavy borders, clean status line)
• Auto-width columns based on content
• Pending command display (shows g_, z_, 5_)
• Out-of-bounds errors (not silent clamping)
• NEW v0.4.0: Insert mode - i, a, I, A, s for cell editing
• NEW v0.4.0: Text editing - Backspace, Delete, Ctrl+h, Ctrl+w, Ctrl+u
• NEW v0.4.0: Row operations - o, O, dd, yy, p for rows
• NEW v0.4.0: Clear cells with Delete key in Normal mode
• Comprehensive test suite (408+ tests passing)
• Search and persistence coming in v0.4.1+

Current: v0.4.0 Complete | Performance: 60 FPS on 100K+ rows | Architecture: Clean, type-safe, well-tested

What's New in v0.4.0

v0.4.0 - Insert Mode:

• Enter Insert mode: i, a, I, A, s, or F2 on any cell
  • i - edit at cursor position
  • a - edit at end of cell
  • I - edit at start of cell
  • A - same as a
  • s - clear cell and enter Insert mode
  • F2 - edit cell (Excel/Calc style)
• Text editing in Insert mode:
  • Type to insert characters
  • Backspace or Ctrl+h - delete before cursor
  • Delete - delete at cursor
  • Ctrl+w - delete word backward
  • Ctrl+u - delete to start of cell
  • Home/End - move to start/end
  • Left/Right arrows - move cursor within cell
• Commit or cancel:
  • Enter - save and move down
  • Shift+Enter - save and move up
  • Tab - save and move right
  • Shift+Tab - save and move left
  • Esc - cancel without saving
• Row operations in Normal mode:
  • o - add row below, enter Insert mode
  • O - add row above, enter Insert mode
  • dd - delete current row (stored in clipboard)
  • yy - copy current row
  • p - paste row below
  • Delete - clear current cell content

Previous Versions

v0.3.0-v0.3.2 - Navigation & UI Polish:

• Row jumping: gg, G, 5G
• Column jumping: :c A, :c 1, :c AA
• Count prefixes: 5j, 10h
• Word motion: w, b, e
• Viewport control: zt, zz, zb
• Status bar with mode indicators
• Help overlay with ?
• No timeout on pending commands

What's New in v0.3.0 & v0.3.1

v0.3.0 - Advanced Navigation:

• Column jumping with Excel notation (ga, gB, gBC)
• Vim-style command mode (:15 for line)
• Word motion for sparse data (w, b, e)
• Viewport positioning (zt, zz, zb)
• Count prefixes (5j, 10h, etc.)

v0.3.1 - UI/UX Polish:

• Mode indicator (-- NORMAL -- / -- COMMAND --)
• Dirty flag display (*)
• Transient messages that auto-clear
• Redesigned help menu with better organization
• File list horizontal scrolling

Philosophy

LazyCSV follows the "lazy tools" design:

1. Keyboard first - mouse optional
2. Fast - instant response, in-memory for speed
3. Simple - no configuration required
4. Powerful - vim-style efficiency
5. Vim-first - if it works in vim, it should work here

License

GPL License - see LICENSE file for details.

Credits

Built with:

• ratatui - TUI framework
• csv - CSV parsing by BurntSushi
• Rust

Inspired by the excellent "lazy" tools: lazygit | lazydocker | lazysql | lazyssh

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Have fun exploring your data!