In designing Git Work, I must analyse other relevant services.
I'm publishing this article as a draft so it's out there and I can get feedback from you guys, perhaps I missed something?
Codemill
- "Marketplace for pull requests", so focused on pull requests
 - Integrated with GitHub
 - Requires sign in to see the available work
 - "Pull work" approach, the Worker is in control
 - Nothing about disputes
 - Has an alerting system
 - Charge per piece of work
 - 10% commission
 - "[..] elastic, scalable, on demand and pay-as-you-go development power [..]" source.
 
BountySource
- "Bountysource is the funding platform for open-source software"
 - No support for private projects
 - Unit of work is an Issue, with a link to a PR
 - Bounties offered by users
 - Bounties potentially from multiple users
 - Not ties to a specific workflow
 - Comprehensive integrations including GitHub, and it's open source
 - 10% commission as of 20 April 2017.
 
Upwork
- "Work with someone perfect for your team"
 - Unit of work is a project
 - Bidding and proposal process (write a cover letter!)
 - Reputation and reviews
 - Work is mostly large, per-project
 - Freelancers offer free consultations during bidding
 - Act as Escrow, has complex dispute resolution
 - Hourly charge, estimate number of hours
 - 2.75% + 20%/10%/5% commission as of 20 April 2017.
 
Toptal
- "Hire the top 3% of freelance talent"
 - Hiring is based on passing their tests and interviews
 - "interview [..] 40 hours of your time" source.
 - $500 deposit
 - Charged per hour/week/etc, looks per-project
 - Unclear how work is agreed upon
 - Dispute process is unclear
 
LinkedIn ProFinder
- "ProFinder helps you hire top local freelancers"
 - Proposal driven process, similar to Toptal
 - Pricing: after 10 proposals, requires LinkedIn Premium Business account
 - Beyond software development, they mention accountants for example
 
Usage
Some people use these services as a springboard.
    
Top comments (1)
Great resource - thank you!