Open Source ROI Model

Here are some loose thoughts on Open Source contribution Return On Investment (ROI):

I once created a game called TuxBucks which tried to model the dynamics of open source ROI.

Below is a list of some factors affecting open source ROI, which I think would be good to model. I have no idea, for most of these, how to come up with realistic values for these factors.

Overview

• Total return from open source = amount of code that is relevant to your product, minus acquisition and integration cost, minus participation cost

• • Let RP = amount of code relevant to your product
  • Let AC = acquisition cost
  • Let IC = integration cost
  • Let PC = participation cost
• the formula becomes ROI = RP - AC - IC - PC

• Acquisition cost = license fees plus subscription fees plus downloading costs
  • downloading costs = cost to train inexperienced engineers in downloading plus cost to download
  • Integration cost = finding cost plus conflict resolution cost plus adaptation cost plus quality assurance cost
  • Finding cost = cost to train inexperienced engineers in finding plus search time plus downloading cost plus evaluation cost
  • conflict resolution cost = cost to resolve patch conflicts
    • Conflict resolution depends on patch series breadth (patch locality), and magnitude of version gap (among other things)

Effect of mainlining code

• what costs go up in order to mainline code?
  • cost to generalize code (very hard to gauge?)
  • cost to convert code to submission standards
  • cost to forward-port code to the latest project version
    • may be unavoidable if your code is dependent on other items (especially board support or architecture code)
    • could factor in cost to forward-port the board support or architecture code
• what costs go down as a result of mainlined code?

Effect of not being current with your source code version

• What is effect of not being current?
  • raises mainlining cost (see mainlining code costs)

Effect of experience with open source

• What are switching costs for developers entering open source work?
  • How expensive is it to learn diff+patches or git, for example?
  • What is the magnitude of the learning curve for participating?
  • Does the learning curve increase over time (I believe it does, as complexity of code bases grow)
• Can this be measured by examining

Dynamics of network effects

• What number of contributors is needed before open source becomes useful?
  • number of contributors affects amount of contributions
  • skill of contributors affects value of contributions
  • amount and value of contributions affects the total code base size
  • total code base value affects likelihood of code relevance to product (really?)
• Can this be modeled, realistically?

Dynamics of participation costs

• as participation increasing, training cost go down
  • finding cost is reduced
  • mainlinging cost is reduced
  • integration cost is reduced??