Mention plan for integrated build tool with test framework

Author: schoen

docs/resources/roadmap.md

@@ -48,3 +48,7 @@ We're creating tools and examples for integrating other data sources into Simpli
 ## Sample applications
 
 We're developing prototypes of several real financial applications on Simplicity, including collateralized lending mechanisms and options contracts. You can see work in progress on some of these at <https://github.com/BlockstreamResearch/simplicity-contracts>.
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+## Integrated build system and package manager
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+We're prototyping a tool, somewhat akin to `cargo` or `go`, providing package management, development workflow, and test orchestration features. This tool will provide a test framework support unit and integration tests, including running integration tests against a regtest environment to simulate the effects of multiple related transactions.