Bash vs Python Scripting Guide | Generated by AI
Question: When should I use a Bash/shell script (.sh) versus a Python script? Bash seems very convenient for many tasks, but sometimes Python feels simpler — how do I decide which one to use?
Answer:
Here’s a practical decision guide that most experienced developers use:
| Situation | Prefer Bash (.sh) | Prefer Python |
|---|---|---|
| Gluing together existing command-line tools (grep, awk, sed, jq, ffmpeg, etc.) | ✅ Very strong | ⚠️ Overkill |
| Quick one-liners or short automation (< ~50 lines) | ✅ Extremely fast to write and run | ⚠️ Slower startup, more boilerplate |
| Running only on Linux/macOS servers or in CI/CD | ✅ Native, zero dependencies | ⚠️ Need Python installed |
| Heavy text processing with regexes | ✅ With grep/sed/awk — often fastest | ✅ With re module — more readable for complex cases |
| Complex logic, data structures (lists, dicts, classes), algorithms | ⚠️ Painful and error-prone | ✅ Natural and safe |
| Error handling, logging, testing, refactoring | ⚠️ Primitive | ✅ Excellent |
| Working with JSON, YAML, APIs, databases, CSV | ⚠️ Clumsy (jq helps, but still limited) | ✅ Libraries make it trivial |
| Need to run the script on Windows without WSL | ❌ Very painful | ✅ Just works (or PyInstaller for standalone exe) |
| Performance matters and you’re doing heavy CPU work | ⚠️ Slow for loops | ✅ Much faster (or call C extensions) |
| You or your team will maintain this script in 6–12 months | Only if it stays tiny | ✅ Almost always |
| You need virtual environments or dependency management | ❌ Impossible | ✅ pip/venv/poetry |
Quick decision flowchart (mental model)
-
Can I do it in ≤ 20 lines using mostly standard UNIX tools piped together?
→ Use Bash - Do I need any of these:
- Nested data structures
- Proper functions with local variables
- Real error handling/classes/modules
- Libraries (requests, pandas, sqlalchemy, etc.)
- Unit tests
→ Use Python
-
Is it a cron job that runs for < 2 seconds and just moves files, restarts services, does simple grep/awk?
→ Bash is perfect - Will this script grow over time or be edited by multiple people?
→ Start with Python from day one
Common sweet spots
- Bash/sh:
- Deployment scripts (calling docker, kubectl, terraform)
- System administration one-offs
- Makefile helpers
- Git hooks (sometimes)
- Python:
- Any script > 100 lines
- Anything that talks to HTTP APIs
- Data processing pipelines
- DevOps tools you publish to others (e.g. cookiecutter templates, CLI tools with click/typer)
Hybrid approach (best of both worlds)
Very common and recommended:
#!/usr/bin/env bash
# Small bash wrapper
python3 - <<'PY'
# Your complex logic in Python
import json, sys, requests
...
PY
Or call Python from Bash when needed:
data=$(python3 -c "import json, sys; print(json.load(sys.stdin)['key'])" <<< "$json")
Bottom line:
Use Bash when it’s obviously simpler and stays tiny.
Switch to (or start with) Python the moment you feel any friction with data structures, error handling, or readability. Most people regret writing large Bash scripts, but almost nobody regrets choosing Python for automation.