Why Skylos?

The Analysis Tool Landscape

There are many static analysis tools for Python. Here’s how Skylos fits in:

Feature Comparison

Capability	Skylos	Bandit	Semgrep	Vulture	Pylint
Dead code detection	✅	❌	❌	✅	Partial
Taint analysis	✅	❌	✅	❌	❌
Framework awareness	✅	❌	Partial	❌	❌
Complexity metrics	✅	❌	❌	❌	✅
Secret detection	✅	❌	✅	❌	❌
Quality gate	✅	❌	❌	❌	❌
AI-powered fixes	✅	❌	❌	❌	❌
TypeScript support	✅	❌	✅	❌	❌
Confidence scoring	✅	❌	❌	Partial	❌
Interactive removal	✅	❌	❌	❌	❌

Tool-by-Tool Comparison

vs Bandit
vs Semgrep
vs Vulture
vs Pylint
vs Snyk Code

Bandit

What it does: Security-focused linter using AST pattern matching.Limitations:

No taint analysis—misses indirect vulnerabilities
No dead code detection
No quality metrics
No framework awareness (high false positives)

# Bandit catches this:
eval(user_input)  # ✅ B307: eval detected

# Bandit misses this:
data = user_input
query = data
cursor.execute(query)  # ❌ No SQL injection warning

When to use Bandit: Quick security audit when you don’t need depth.When to use Skylos: Production security where indirect vulnerabilities matter.

Vulture

What it does: Dead code detection via AST analysis.Limitations:

No security scanning
No quality metrics
Limited framework awareness
No confidence scoring
No interactive removal

# Vulture flags this as unused:
@app.route('/users')  # ❌ False positive
def get_users():
    return users

When to use Vulture: Simple dead code check on non-framework code.When to use Skylos: Framework-aware detection with confidence filtering.

The Skylos Difference

1. All-in-One Analysis

Most tools focus on one thing. Skylos combines three: One tool, one config, one CI step—not three separate pipelines.

2. Framework Awareness Reduces Noise

Other tools don’t understand Django, Flask, or FastAPI:

# What other tools see:
@app.route('/api/users')
def get_users():  # "Unused function"
    return jsonify(users)

# What Skylos sees:
@app.route('/api/users')
def get_users():  # Not flagged—called by framework
    return jsonify(users)

3. Confidence Scoring Filters Uncertainty

Instead of boolean “used/unused”, Skylos scores confidence:

Finding	Confidence	Other Tools	Skylos
`def _helper()`	20%	Flagged	Filtered out
`def __str__()`	0%	Flagged	Excluded
`def unused_fn()`	85%	Flagged	Reported

4. Taint Analysis Catches Real Vulnerabilities

Pattern matching finds obvious issues. Taint analysis follows data flow:

5. Built-in Quality Gate

No scripting required to block bad PRs:

# Other tools: requires wrapper script
bandit -r . -f json > report.json
python check_results.py report.json || exit 1

# Skylos: built-in
skylos . --danger --gate

Migration Guide

From Vulture

# Before
vulture myproject/ --min-confidence 80

# After
skylos myproject/ --confidence 80

Skylos uses similar confidence scoring but adds framework awareness.

From Bandit

# Before
bandit -r myproject/ -f json -o bandit.json

# After
skylos myproject/ --danger --json -o skylos.json

Skylos includes all Bandit-style checks plus taint analysis.

From Pylint (complexity only)

# Before
pylint myproject/ --disable=all --enable=R0912,R0915

# After
skylos myproject/ --quality

Skylos focuses on actionable metrics, not style.

When to Use Multiple Tools

Skylos doesn’t replace everything. Consider combining:

Use Case	Recommendation
Code formatting	Use Black/Prettier (not Skylos)
Type checking	Use mypy/Pyright (not Skylos)
Dead code + Security + Quality	Use Skylos
Custom security rules	Use Semgrep + Skylos
Supply chain analysis	Use Snyk/Dependabot + Skylos

Try It Yourself

pip install skylos

skylos . --danger --quality --secrets

Overview

Concepts

Product: Scan

Product: Gate

Product: Fix

Tutorial

Reference

The Analysis Tool Landscape

Feature Comparison

Tool-by-Tool Comparison

Bandit

Semgrep

Vulture

Pylint

Snyk Code

The Skylos Difference

1. All-in-One Analysis

2. Framework Awareness Reduces Noise

3. Confidence Scoring Filters Uncertainty

4. Taint Analysis Catches Real Vulnerabilities

5. Built-in Quality Gate

Migration Guide

From Vulture

From Bandit

From Pylint (complexity only)

When to Use Multiple Tools

Try It Yourself

Next Steps

Getting Started

Security Analysis

Overview

Concepts

Product: Scan

Product: Gate

Product: Fix

Tutorial

Reference

​The Analysis Tool Landscape

​Feature Comparison

​Tool-by-Tool Comparison

​Bandit

​Semgrep

​Vulture

​Pylint

​Snyk Code

​The Skylos Difference

​1. All-in-One Analysis

​2. Framework Awareness Reduces Noise

​3. Confidence Scoring Filters Uncertainty

​4. Taint Analysis Catches Real Vulnerabilities

​5. Built-in Quality Gate

​Migration Guide

​From Vulture

​From Bandit

​From Pylint (complexity only)

​When to Use Multiple Tools

​Try It Yourself

​Next Steps

Getting Started

Security Analysis

The Analysis Tool Landscape

Feature Comparison

Tool-by-Tool Comparison

Bandit

Semgrep

Vulture

Pylint

Snyk Code

The Skylos Difference

1. All-in-One Analysis

2. Framework Awareness Reduces Noise

3. Confidence Scoring Filters Uncertainty

4. Taint Analysis Catches Real Vulnerabilities

5. Built-in Quality Gate

Migration Guide

From Vulture

From Bandit

From Pylint (complexity only)

When to Use Multiple Tools

Try It Yourself

Next Steps