denali build --print-slow-trees=true
cli v0.0.12 [local] | denali v0.0.29 [local]
✖ Build failed
TypeError: broccoli_slow_trees_1.default is not a function
at Project.finishBuild (/Users/daw/projects/oss/denali/denali-cli/lib/project.ts:320:21)
at Project.<anonymous> (/Users/daw/projects/oss/denali/denali-cli/lib/project.ts:193:12)
at Generator.next (<anonymous>)
at fulfilled (./node_modules/tslib/tslib.js:93:62)
at <anonymous>
at process._tickDomainCallback (internal/process/next_tick.js:228:7)
As reported by @seawatts in denali-js/denali#374: