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DEV-111 Development

Modern JavaScript & TypeScript

Build the language fluency every web and Node course assumes: modern JavaScript semantics, the event loop, module systems, and a working TypeScript type discipline. Learners finish able to read and write typed application code, explain why an async result arrived in the order it did, and defend a bundler and test setup they configured themselves.

B2Foundation
6modules
42skill atoms
3role journeys
Curriculum

What this course covers.

6 modules, 42 named skill atoms. Expand any module to see them.

1Language Core7 skill atoms
let and const scopingclosuresprototypes and this bindingdestructuringspread and restoptional chainingnullish coalescing
2Async & the Event Loop7 skill atoms
call stack and task queuemicrotasks vs macrotaskspromise combinatorsasync/await error handlingabortcontrollerunhandled rejection trapslong-task starvation
3Typing with TypeScript7 skill atoms
structural typinginterfaces vs type aliasesunion and literal typesstrictnullchecksany vs unknowntype assertions and their costdeclaration files
4Generics & Narrowing7 skill atoms
generic functionsconstraints with extendskeyof and indexed accessmapped typesconditional typesdiscriminated unionscustom type guards
5Modules, Bundlers & Tests7 skill atoms
esm import and exportesm vs cjs interoptree shakingvite and esbuild configvitest and jest setupmodule mockingcoverage thresholds
6AI Assistants in JavaScript Work7 skill atoms
scaffolding vs understandingreviewing generated type definitionsstale ecmascript and node api suggestionshallucinated npm packagesany creep in generated codeconfidently wrong async orderingengineer accountable for runtime behaviour
Where it fits

DEV-111 in the role journeys.

This course appears in 3 of our 45 role journeys. Here is what a learner takes immediately before and after it in each.

Full-Stack Developer

Foundation stage
AI-101DEV-111DEV-211

Frontend Engineer

Foundation stage
AI-101DEV-111DEV-211

Mobile Developer

Foundation stage
AI-101DEV-111DEV-221

Roles this course serves

The capability ladder

This course is authored to band B2.

Every course we run is written to one rung of the CASI ladder, so a plan can be assembled to take a team from where they are to where they need to be.

What do B1–B6 mean?The CASI Capability Ladder — click to expand

Every course targets a band on the CASI Capability Ladder — our six-band proficiency scale, anchored to open standards (O*NET, ESCO, NICE, NIST AI RMF, Bloom's). A band tells you how deep a course goes, and what evidence proves it.

What the learner can doTypical evidence
B1
AwareUnderstands concepts and vocabulary; uses tools with guidance
Knowledge checks
B2
FoundationPerforms standard tasks correctly in familiar contexts
Guided labs, autograded exercises
B3
PractitionerDelivers complete pieces of work independently
Scenario labs, proctored hands-on exams
B4
ProfessionalHandles production-grade complexity, trade-offs and failure modes
Break-fix drills, design defenses
B5
AdvancedEngineers systems end-to-end under constraints; leads others
Rubric-scored capstones, vivas
B6
ExpertSets direction; recognised authority across teams
Portfolio + panel evaluation

A note on B6. Courses in this catalog target B1–B5. B6 is not taught — it is recognised, through a portfolio and a panel, once someone is setting direction for others. Every journey here is built to land a learner at B5.

Next step

Run DEV-111 for your team.

This course runs at several lengths depending on how deep you need to go and how much of it your people already have. Tell us who is being trained and we will scope it.

Add it to a training plan Talk to our team Check your team’s level free