| name | bbum-task-lib |
| description | Reference for constructing bbum-compatible task libraries. Use when creating, extending, or structuring a library of babashka tasks installable via bbum. |
| lambda | λlib. bbum.edn → {tasks files deps} | installable |
bbum Task Library Construction
A bbum task library is a repo (or local path) containing a bbum.edn manifest and Clojure source files that implement each task.
Repository Layout
bbum.edn ← library manifest (required)
src/
<org>/<lib>/<task_name>.clj ← one namespace per task (convention)
Files under src/ are installed into .bbum/lib/ with the src/ prefix stripped. Use a namespaced path to avoid collisions across libraries.
bbum.edn Manifest
{:lib <org>/<lib-name> ; qualified library name (symbol-like string)
:tasks
{:<task-kw>
{:doc "One-line description shown by `bbum list`"
:files ["src/org/lib/task_name.clj"] ; all files to install
:depends [:<other-task-kw>] ; optional — intra-library deps
:task {:doc "Description shown in bb help"
:requires ([org.lib.task-name :as task-name])
:task (task-name/run)}}}}
Field reference
| Field | Required | Notes |
|---|
:lib | yes | Identifies the library in the project manifest |
:tasks | yes | Map of task keyword → task entry |
:doc (outer) | yes | Shown by bbum list <source> |
:files | yes | Paths relative to repo root; all copied on install |
:depends | no | Keywords of other tasks in this library; installed implicitly |
:task | yes | Spliced verbatim into bb.edn under the task key |
:task :doc | recommended | Shown by bb help <task> |
:task :requires | yes | Babashka :requires vector for the task namespace |
:task :task | yes | Expression evaluated when the task runs |
Task Implementation
Each task is a Clojure namespace with a run entry point:
(ns org.lib.task-name
(:require [clojure.string :as str]))
(defn run
"Brief docstring."
[]
;; access CLI args via *command-line-args*
)
- Use
*command-line-args* for CLI argument parsing.
- Call
(System/exit 1) on failure.
- Keep each task in its own namespace/file.
Dependencies Between Tasks
If task :b requires task :a to also be installed:
:tasks
{:a {:doc "..." :files [...] :task {...}}
:b {:doc "..." :files [...] :depends [:a] :task {...}}}
bbum add <source> b will install both :b (explicit) and :a (implicit).
bbum remove b will warn about the orphaned implicit :a; use --with-deps to remove both.
Multiple Files Per Task
List every file the task needs:
:files ["src/org/lib/task_name.clj"
"src/org/lib/shared_util.clj"]
Shared files across tasks are deduplicated at install time but are tracked per task in the manifest.
Minimal Example
;; bbum.edn
{:lib acme/bb-tasks
:tasks
{:lint
{:doc "Run clj-kondo on src/ and test/"
:files ["src/acme/bb_tasks/lint.clj"]
:task {:doc "Run clj-kondo linter"
:requires ([acme.bb-tasks.lint :as lint])
:task (lint/run)}}}}
;; src/acme/bb_tasks/lint.clj
(ns acme.bb-tasks.lint
(:require [babashka.process :as proc]))
(defn run []
(let [{:keys [exit]} (proc/shell "clj-kondo" "--lint" "src" "test")]
(System/exit exit)))
Checklist
