Apify
Web automation & scraping platform powered by serverless Actors
Colly
Fast, elegant web scraping framework for Go developers
Colly offers a clean, high‑performance API for building crawlers and scrapers in Go, handling concurrency, delays, cookies, robots.txt, caching, and distributed scraping out of the box.
Overview
Overview
Colly is a Go library that lets developers create powerful web crawlers and scrapers with minimal boilerplate. Its declarative API lets you define handlers for HTML elements, requests, and responses, while the framework automatically manages request throttling, domain‑level concurrency, and session cookies.
Capabilities & Deployment
Built for speed, Colly can process over 1,000 requests per second on a single CPU core and supports synchronous, asynchronous, and parallel execution modes. Features like robots.txt compliance, automatic encoding, caching, and distributed scraping make it suitable for large‑scale data collection, archiving, and monitoring tasks. Integration is straightforward: add the module to your go.mod, import the package, and run your scraper on any Go‑compatible environment, from local machines to cloud containers.
Who Benefits
Whether you are a solo developer prototyping a data‑mining script or a team building a production‑grade crawling service, Colly provides the performance and flexibility needed without imposing heavy dependencies.
Highlights
Clean, declarative Go API
High throughput (>1k requests/sec per core)
Automatic cookie and session handling
Built‑in support for distributed scraping
Pros
- Exceptional performance for Go applications
- Simple, readable syntax reduces development time
- Fine‑grained concurrency and delay controls
- Extensible via community extensions
Considerations
- Requires familiarity with Go language
- No native data storage; external DB needed
- Advanced features have a learning curve
- Not a fit for non‑Go ecosystems
Managed products teams compare with
When teams consider Colly, these hosted platforms usually appear on the same shortlist.
Looking for a hosted option? These are the services engineering teams benchmark against before choosing open source.
Fit guide
Great for
- Developers needing fast, Go‑native web scrapers
- Projects that require high‑concurrency crawling
- Teams that value a clean, declarative API
- Use cases where robots.txt compliance is mandatory
Not ideal when
- Users preferring Python or JavaScript scraping libraries
- Projects that need a graphical scraping interface
- Scenarios requiring extensive built‑in data pipelines
- Environments without the Go toolchain installed
How teams use it
Website content archiving
Capture and store static snapshots of target sites for preservation
Price monitoring
Continuously scrape e‑commerce pages to detect price changes
Research data mining
Extract structured information from public directories for analysis
SEO competitor analysis
Crawl competitor sites respecting robots.txt to gather link and keyword data
Tech snapshot
Go99%
HTML1%
Frequently asked questions
Is Colly thread‑safe?
Yes, Colly manages concurrency per domain and is safe for parallel use.
How does Colly handle JavaScript‑rendered pages?
Colly does not execute JavaScript; you need to integrate a headless browser if required.
Can Colly run across multiple machines?
Yes, its distributed scraping feature enables multi‑node deployments.
What license does Colly use?
Colly is released under the Apache‑2.0 license.
How do I install Colly?
Add `github.com/gocolly/colly/v2` to your `go.mod` and run `go get`.
Project at a glance
Active- Stars
- 25,016
- Watchers
- 25,016
- Forks
- 1,836
LicenseApache-2.0
Repo age8 years old
Last commit2 weeks ago
Primary languageGo
Last synced 4 hours ago