Civic Innovations<p><strong>Revisiting an Old Idea: Building a Rules Engine with CouchDB</strong></p><p>A few years back, while working at 18F, I created <a href="https://github.com/mheadd/couch-rules-engine" rel="nofollow noopener" target="_blank">a prototype</a> that explored something a bit unconventional: using CouchDB’s document validation functions as the foundation for a rules engine. The idea was to leverage CouchDB’s built-in validation capabilities to create business rules that could be applied to documents as they’re inserted or updated.</p><p>I’ve always been somewhat obsessed with <a href="https://couchdb.apache.org/" rel="nofollow noopener" target="_blank">CouchDB</a>—there’s something elegant about its document-oriented approach and the way it handles replication, versioning, and distributed architectures. (<a href="https://www.youtube.com/watch?v=2sE7bY76kag" rel="nofollow noopener" target="_blank">Here’s a video I made over 10 years ago</a> showing how to load polling location data into a CouchDB instance.) So even though my prototype remained just that, the concept has continued to bubble in the back of my brain.</p><p>Recently, I decided to dust off this old project and give it the attention it deserves. I’ve worked to develop <a href="https://github.com/mheadd/couch-rules-engine/blob/main/ROADMAP.md" rel="nofollow noopener" target="_blank">a comprehensive roadmap</a> to transform the basic prototype into a more functional and usable product that truly leverages CouchDB’s unique strengths.</p><p><strong>What Makes This Interesting</strong></p><p>Instead of building yet another traditional rules engine, this approach uses CouchDB’s native validation functions as the rule execution environment. This means:</p><ul><li><strong>Native versioning</strong> through <a href="https://docs.couchdb.org/en/stable/api/document/common.html" rel="nofollow noopener" target="_blank">CouchDB’s document revision system</a></li><li><strong>Built-in replication</strong> for <a href="https://docs.couchdb.org/en/stable/replication/intro.html" rel="nofollow noopener" target="_blank">distributing rules across environments</a></li><li><strong>RESTful rule management</strong> using <a href="https://docs.couchdb.org/en/stable/api/index.html" rel="nofollow noopener" target="_blank">CouchDB’s HTTP API</a></li><li><strong>Distributed validation</strong> that scales with <a href="https://docs.couchdb.org/en/stable/cluster/index.html" rel="nofollow noopener" target="_blank">CouchDB clusters</a></li></ul><p>The roadmap I’ve created takes my earlier work from a proof-of-concept to a (hopefully) production-ready system with a web-based rule management interface, comprehensive testing infrastructure, and advanced rule capabilities—all while maintaining the elegance of the core CouchDB foundation.</p><p><strong>Looking Ahead</strong></p><p>Over the next few weeks (again, hopefully), I’ll be working through the development phases, starting with a modern testing framework and a clean web interface for rule management. The goal is to create something that demonstrates how CouchDB’s unique features can be leveraged in ways that traditional databases simply can’t match.</p><p>If you’re interested in following along or have thoughts about creative uses for CouchDB, <a href="https://github.com/mheadd/couch-rules-engine/issues" rel="nofollow noopener" target="_blank">I’d love to hear from you</a>. Sometimes the most interesting solutions come from pushing familiar tools in unexpected directions.</p><p><a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/art/" target="_blank">#art</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/books/" target="_blank">#books</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/couchdb/" target="_blank">#CouchDB</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/governmet/" target="_blank">#governmet</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/javascript/" target="_blank">#Javascript</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/open-source/" target="_blank">#OpenSource</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/politics/" target="_blank">#politics</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/rules/" target="_blank">#rules</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/service-delivery/" target="_blank">#serviceDelivery</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/software/" target="_blank">#software</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://civic.io/tag/technology/" target="_blank">#technology</a></p>