biwa

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About ​

biwa is a modern CLI tool designed to bridge the gap between local comfort and remote necessity. It allows you to develop locally with your preferred tools while seamlessly running code on UNSW CSE infrastructure.

Evolution from cserun ​

biwa is the spiritual successor to cserun. We are deeply grateful to Bojin, the author of cserun, for pioneering this approach and providing the tool that inspired biwa.

biwa supports all usages of cserun while introducing significant improvements:

  • Superset of Features: Everything you could do in cserun, you can do in biwa.
  • Active Maintenance: Built to be maintained and improved for the long term.
  • Smart Environment: No need to manually set environments for every call.
  • Symlink Support: Seamlessly handles CSE symlinks (like 1511 or specific standard libraries).

Core Philosophy: Develop Locally ​

The core philosophy of biwa is simple: You should develop on your own machine.

CSE servers are shared resources. They are not designed to host VS Code servers for hundreds of students, nor do they have the disk space for modern node_modules or build artifacts.

biwa enables a Local-First Workflow:

  1. Edit Locally: Use VS Code, Neovim, IntelliJ, or any editor you love with zero latency.
  2. Build Locally: Run fast feedback loops on your own hardware.
  3. Execute Remotely: When you need to run autotest, give, or use specific CSE compilers, biwa handles it instantly.

The Problem with Remote Development ​

When working on UNSW CSE coursework, you often face a dilemma: work locally comfortably but struggle with submission/testing, or work remotely on CSE servers but deal with latency and restrictions.

Challenges of CSE Servers ​

  • Latency & Disconnects: SSH connections can be unstable, leading to laggy typing or dropped connections.
  • Disk Quotas: CSE servers have strict disk limits. Installing modern tools or even running npm install can quickly exhaust your quota.
  • Resource Limits: Heavy processes are killed, and persistent background tasks are discouraged.
  • Tooling Limitations: You can't easily install your favorite shell, editor plugins, or system dependencies.

Why Not Alternatives? ​

Raw SSH ​

The traditional approach: ssh z5555555@cse.unsw.edu.au

  • Manual Sync: You must manually copy files back and forth (scp/rsync).
  • Context Switching: Constant switching between local editor and remote terminal breaks flow.
  • Repetitive: Typing server details and passwords/keys repeatedly.

VS Code Remote SSH ​

The popular extension

  • Banned / Unstable on CSE: CSE servers aggressively kill the heavy "zombie" processes that VS Code leaves behind. This forcibly disconnects your session, requires a window reload, and often loses your terminal state.
  • Resource Limits: Because it runs a full Node.js server for each user, it consumes significant resources, leading to system instability—the primary reason it is restricted on shared servers.

SSH FS / SFTP Extensions ​

The filesystem mount approach

  • Slow Performance: Every file save or read requires a network round-trip.
  • Incompatible with node_modules: Dependency directories like node_modules often fail to work correctly on mounted volumes, or npm install takes an agonizingly long time due to thousands of small file operations.
  • Network Dependency: If your internet blips, your editor hangs.

VNC / VLab ​

The graphical desktop approach

  • High Latency: transmitting a full desktop UI over the internet is bandwidth-intensive and feels sluggish.
  • Overkill: You usually just need a terminal and an editor, not a full Linux desktop environment.

The biwa Solution ​

biwa handles the complexity so you don't have to.

Seamless Remote Execution ​

When you need to run a CSE-specific command (like autotest, give, or a specific compiler version), biwa handles it instantly:

  • Smart Sync (rsync): Unlike cserun which clones the directory from scratch every time (wasting disk space and time), biwa uses rsync to synchronize only changed files.
  • Direct Command Execution: Run CSE commands directly. For example, you can run biwa 1511 or biwa Give without needing biwa run.
  • Auto-Cleanup: Manages remote directories automatically. If you haven't touched a project in a while, biwa cleans it up to save your remote disk quota.
  • Transient: No heavy background processes left running on the server.