May 2023: Bazel UX: Flags and CLI (Ulf Adams @ EngFlow)

During the Bazel Community Day held in San Francisco on May 23rd 2023, Ulf Adams from EngFlow (www.engflow.com/) talked about the UX of Bazel, focusing on Bazel's flags and its terminal output when using the CLI.
Ulf Adams, the co-founder and CTO of EngFlow and one of the original authors of Bazel, shared his thoughts on the Bazel command line user experience.
In the first half of the talk, Ulf recommended reorganizing Bazel's nearly 600 flags into six categories to aid understanding and to surface flags that are frequently used.
1. Debug - flags that change how Bazel displays information about what is happening during a build.
2. Input - flags that change how Bazel sees the work, affecting workspace layout, what is considered source, which targets are built, and which platforms they are built for.
3. Rules - language-specific flags that change Bazel's behavior for built-in rules.
4. Migration - flags that support the controlled rollout of semantic changes to Bazel and its rules including changes to Starlark, the rule API, and rule semantics.
5. Strategy - flag that change how Bazel executes actions including caching, sandboxing, remote execution, and test sharding.
6. Meta - low-level flags that affect how Bazel works internally, mostly dealing with in-memory caches and out-of-memory errors.
Spreadsheet of Flags: tinyurl.com/ba...
In the second half of the talk, Ulf spoke about Bazel's terminal output during a build and suggested ways it could surface errors and other relevant information to users more clearly.
Learn more about Bazel events hosted by EngFlow:
www.engflow.co...