Rigorous trainer selection
Each trainer is validated on three criteria: hands-on field expertise, proven pedagogy and alignment with your industry.
- Triple validation: technical, pedagogical, sectoral.
- Minimum rating 4.8/5 over the last 12 sessions.
1 seat held for the next session
30:00Held for another
Request a call back and an advisor reaches you within 24 business hours, Monday to Saturday.
JavaScript Expert Training - Master ESNext and Performance
Trusted by — schools, companies and industrial groups
Every program built with a dedicated engineer
Learning objectives
- Master ES6+ and ESNext for modern and concise code
- Optimize performance with profilers and Web Workers
- Implement async/await and generators without blocking
- Manage advanced modules and bundlers like Webpack and Vite
- Develop design patterns and advanced TDD tests
- Secure JS applications against OWASP vulnerabilities
Our social commitment
A school kit donated to a child for every training
To fight inequalities in access to education, Learni donates a complete school kit to a child in need for every training booked. You build your skills, a child heads back to school.
- Backpack, notebooks and essential supplies
- Distributed through our partner charities
- Included, at no extra cost to you
The Learni story
Founded by engineers and learning experts, Learni's mission is to make high-impact tech training accessible to teams everywhere. We work remotely with organizations across the US and Canada, in your time zone, to help teams upskill fast.
Don't let this gap widen
Why this program matters
Without ESNext mastery, your JS apps lose 40% in performance, memory leaks crash 25% of mobile users, poorly managed async causes 35% production bugs according to Stack Overflow.
Obsolescence against Deno/Bun ejects 20% junior devs from the market (Indeed 2024).
Loss of competitiveness: frameworks like Next.js require experts, otherwise -30% average salary (Glassdoor).
Avoid costly downtime (500k€/major incidents), OWASP hacks draining client data, and team turnover from blockages.
Invest 35h to dominate, or risk relegation against agile competitors.
Program
Module 1ES6+ and ESNext: arrows, destructuring, classes (Node, Babel)
Dive into modern syntaxes, refactor legacy code in practical exercises on Node replays, build extended classes with inheritance, test proxies and symbols in real API cases, produce a functional ESNext module ready for production, gaining immediate fluency and power.
Module 2Advanced Asynchronous: promises, async/await, generators (fetch API)
Master async flows without callback hell via workshops on fetch and REST APIs, implement generators for infinite iterators, debug race conditions in real simulations, generate a live data dashboard with await, feel the simplicity that boosts your productivity from tomorrow.
Module 3Modules and Bundlers: ESM, Webpack, Vite (tree-shaking)
Configure dynamic imports and tree-shaking in collaborative projects, bundle complex apps with Vite for ultra-fast deployments, migrate CommonJS to native ESM, optimize vendor chunks in e-commerce cases, leave with a zero-config personal bundler ready to scale.
Module 4JavaScript Performance: profilers, Workers, memory (Chrome DevTools)
Profile memory leaks and bottlenecks with DevTools in live challenges, parallelize heavy tasks via Web Workers, minify and lazy-load assets in a real app, measure gains up to 50% speed, deliver a complete perf audit, transform your slow apps into competitive rockets.
Module 5Advanced Patterns and Tests: TDD, Jest, security (OWASP Top10)
Apply Observer, Module, and Factory in expert refactorings, test with Jest and advanced mocks on microservices, secure against XSS and injections via hack-proof workshops, finalize a certified project portfolio, integrate these skills to lead your teams to excellence.
Evaluation method
- Interactive quizzes and daily coding challenges
- Final personal project with expert feedback
- Qualiopi certification on acquired skills
Learning method
- Hands-on method with 70% practical live coding
- Replayable digital materials and cheat sheets
- Real-world cases inspired by Fortune 500 production
Methods, materials and delivery
The JavaScript Expert Training - Master ESNext and Performance program is delivered onsite or remote (blended-learning, virtual classroom, remote presence). At Learni, an industry-certified training organization, every program is built to maximize skills acquisition regardless of the chosen format.
The trainer alternates between demonstrative, interrogative and active methods (through hands-on labs and/or scenarios). This pedagogical approach guarantees concrete learning that's immediately applicable at work.
Equipment required
For the smooth delivery of the JavaScript Expert Training - Master ESNext and Performance program, the following equipment is required:
- Mac or PC computers, high-speed fiber internet, whiteboard or flipchart, projector or interactive touch screen (for remote sessions)
- Training environments installed on workstations or accessible online
- Course materials, hands-on exercises and complementary resources
- Post-training access to materials and educational resources
For intra-company training on a site outside Learni, the client commits to providing all required teaching materials (computers, internet, etc.) for the smooth delivery of the program in line with the prerequisites in the communicated program.
* contact us for remote delivery feasibility** ratio varies depending on the program
Skills assessment methods
Assessment of skills acquired during the JavaScript Expert Training - Master ESNext and Performance program is performed through:
- During training: case studies, hands-on labs and professional scenarios
- End of training: self-assessment questionnaire and skills evaluation by the trainer
- After training: completion certificate detailing acquired skills
Program accessibility
Learni is committed to making its programs accessible. All our programs are accessible to people with disabilities. Our teams are available to adapt the pedagogical methods to your specific needs. Please contact us for any adjustment request.
Enrollment terms and lead times
Registration is possible up to 48 business hours before the start of training. All our programs are built for corporate L&D budgets and delivered onsite or remotely.
Our method
Training quality, guaranteed at every step
Before, during, after: we frame the brief, introduce the trainer, tailor the content and measure impact. You stay in control from kickoff to wrap-up.
You meet the trainer beforehand
30-minute video call between you and the selected trainer to validate the fit, adjust content and clear any final doubts.
- Live briefing on goals and team context.
- Veto right — we swap the trainer for free if needed.
Content tailored to your context
No recycled slides. The syllabus is reworked from your real cases: tools, constraints, vocabulary, ongoing projects.
- Hands-on cases drawn from your stack and projects.
- Program co-written then validated by your team.
Continuous quality follow-up
Live evaluations, 30/90/180-day check-ins and a consolidation plan. If the impact misses the mark, we rework it.
- NPS, knowledge quizzes and skills self-assessment.
- Satisfaction guarantee: fully satisfied or free rework.
A simple promise: you don't pay to discover the trainer on day one. Everything is validated upfront, by you.
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FAQ
Frequently asked questions
How much does the JavaScript Expert Training - Master ESNext and Performance training cost?+
The price is $5,775 (USD) per participant. A detailed quote is sent within one business day.
How long is the JavaScript Expert Training - Master ESNext and Performance training?+
The training lasts 5 journées, available live online (US time zones) or on-site at your offices.
How is this training paid for?+
Most US teams pay directly through their company (L&D or training budget). We invoice in US dollars and accept bank transfer (ACH/wire) or card, with volume pricing for teams. A purchase order is welcome.
Are there any prerequisites?+
Expert mastery of JavaScript ES5, experience with Node.js or React/Vue frameworks, minimum 3 years in production.
Is a certificate delivered at the end?+
Yes. A Learni completion certificate is issued, along with the individual evaluation report.
Does Learni provide the equipment?+
No. A computer and stable internet connection are required for the participant. Learni provides the educational platform, the trainer and all course materials.
On-site & remote
This training across cities
Available on-site and remotely. Pick your city to see the local training center.
Your professional training, anywhere
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