No one knows your score but you. This is your personal checkpoint.
Future-Ready Training
RxJS Course Built for AI-Paired Learning
RxJS Course at Wisen, Chennai, India, develops practical skills for building asynchronous, event-driven logic with reactive streams. Learn observables, operators, subjects, schedulers, error handling, multicasting, debugging, and testing through AI-Paired Training and project-focused development workflows.
“The right RxJS Course path today can shape your software career tomorrow.”
2700+ Happy Students/Year
Trusted by 30+ Corporate Clients
17,700+ Learners Trained to Date
27+ Years of Training Excellence
Build an AI-Ready Career
Build a Project-Ready Career
Human thinking leads the work. AI assistance accelerates the practice.
Gain Knowledge. Grow Your Career.
RxJS Course Syllabus
The course curriculum for RxJS Course follows a published syllabus with chapter-wise practice, live code review and AI-assisted exercises. It connects RxJS training with state management workflows, so learners build current tooling confidence, project-ready habits and clear career growth. Practice follows.
Chapter 1Reactive Foundations
Reactive Foundations
This chapter focuses on What reactive programming means, Push against pull data models, Promises compared with observables and the practice needed to use these concepts confidently in real projects.
- What reactive programming means
- Push against pull data models
- Promises compared with observables
- Single values against streams
- Where RxJS is used in practice
- Installing and importing RxJS
- The Observable type
- The observer contract
- next, error and complete
- Subscribing to an observable
- The Subscription object
- Unsubscribing and teardown
- Cold observables
- Hot observables
- Making a cold observable hot
- Unicast against multicast
- Synchronous and asynchronous emissions
- Marble diagram notation
- Reading marble diagrams
- The pipeable operator model
- The pipe function
- A first end-to-end stream
Chapter 2Creating Observables
Creating Observables
This chapter focuses on The new Observable constructor, Writing the subscribe function, Returning a teardown function and the practice needed to use these concepts confidently in real projects.
- The new Observable constructor
- Writing the subscribe function
- Returning a teardown function
- of and static values
- from with arrays and iterables
- from with promises
- fromEvent for DOM events
- fromEventPattern for custom sources
- interval and timer
- range
- defer for lazy creation
- EMPTY, NEVER and throwError
- generate for loops as streams
- iif for conditional sources
- Converting callbacks with bindCallback
- bindNodeCallback
- Creating from WebSockets
- Creating from an EventEmitter
- Wrapping an existing API as a stream
- Scheduling on creation
- Testing custom creation functions
- Choosing the right creation function
Chapter 3Transformation Operators
Transformation Operators
This chapter focuses on map, pluck and its replacement, scan for running accumulation and the practice needed to use these concepts confidently in real projects.
- map
- pluck and its replacement
- scan for running accumulation
- reduce and completion
- mergeMap for parallel inner streams
- concatMap for ordered inner streams
- switchMap for latest-only
- exhaustMap for ignoring while busy
- Choosing between the four map operators
- Concurrency limits on mergeMap
- mergeScan
- expand for recursive streams
- toArray
- buffer and bufferTime
- bufferCount and bufferToggle
- window and windowTime
- groupBy
- partition
- pairwise
- Flattening nested data
- Chaining transformations readably
- Common transformation mistakes
Chapter 4Filtering and Timing Operators
Filtering and Timing Operators
This chapter focuses on filter, first and its predicate form, last and the practice needed to use these concepts confidently in real projects.
- filter
- first and its predicate form
- last
- take and takeLast
- takeUntil
- takeWhile
- skip, skipLast and skipUntil
- skipWhile
- distinct
- distinctUntilChanged
- distinctUntilKeyChanged
- debounceTime
- debounce with a duration selector
- throttleTime
- throttle with configuration
- auditTime and sampleTime
- sample with a notifier
- delay and delayWhen
- timeout and timeoutWith
- elementAt
- ignoreElements
- Choosing debounce, throttle or audit
Chapter 5Combination Operators
Combination Operators
This chapter focuses on merge, concat, combineLatest and the practice needed to use these concepts confidently in real projects.
- merge
- concat
- combineLatest
- combineLatest emission rules
- zip
- forkJoin
- forkJoin and the completion requirement
- race
- withLatestFrom
- startWith
- endWith
- concatWith and mergeWith
- switchAll, mergeAll and concatAll
- exhaustAll
- Combining user input with server data
- Dependent sequential requests
- Parallel requests with results together
- Waiting for multiple conditions
- Handling one source that never emits
- Avoiding stalled combinations
- Debugging combination operators
- Choosing the right combinator
Chapter 6Subjects and Multicasting
Subjects and Multicasting
This chapter focuses on What a Subject is, Subject as observer and observable, Multicasting with a Subject and the practice needed to use these concepts confidently in real projects.
- What a Subject is
- Subject as observer and observable
- Multicasting with a Subject
- BehaviorSubject and current value
- ReplaySubject and buffered history
- ReplaySubject with a time window
- AsyncSubject
- Choosing the right Subject
- Subjects as simple state stores
- Exposing asObservable
- Avoiding leaking the Subject
- The share operator
- shareReplay and its configuration
- refCount behaviour
- connectable and connect
- Reference counting pitfalls
- Caching HTTP responses with shareReplay
- Memory leaks from shareReplay
- Event buses and their risks
- Subjects against signals
- Testing subject-based code
- Refactoring subjects to derived streams
Chapter 7Error Handling and Resilience
Error Handling and Resilience
This chapter focuses on How errors terminate a stream, The error callback in subscribe, catchError and the practice needed to use these concepts confidently in real projects.
- How errors terminate a stream
- The error callback in subscribe
- catchError
- Returning a fallback observable
- Rethrowing after logging
- Recovering without killing the outer stream
- catchError placement inside inner streams
- retry and its count
- retry with delay configuration
- Exponential backoff
- retryWhen and its replacement
- Retrying only on specific errors
- finalize for cleanup
- The complete callback
- timeout and error handling
- Handling HTTP error status codes
- Mapping errors to user messages
- Global error handling strategies
- Circuit breaker patterns
- Fallback and degraded modes
- Logging and observability in streams
- Testing error paths
Chapter 8Schedulers, Concurrency and Utility
Schedulers, Concurrency and Utility
This chapter focuses on What a scheduler controls, asyncScheduler, asapScheduler and the practice needed to use these concepts confidently in real projects.
- What a scheduler controls
- asyncScheduler
- asapScheduler
- queueScheduler
- animationFrameScheduler
- observeOn
- subscribeOn
- Choosing a scheduler
- Scheduling and performance
- Avoiding synchronous recursion
- tap for side effects
- tap and debugging streams
- Custom logging operators
- toPromise and its replacement
- firstValueFrom and lastValueFrom
- Default values to avoid EmptyError
- Creating custom operators with pipe
- Higher-order custom operators
- Typing custom operators
- Reusable operator libraries
- Operator composition guidelines
- Keeping streams readable
Chapter 9Real-World Patterns
Real-World Patterns
This chapter focuses on Typeahead search with debounce and switchMap, Cancelling stale requests, Autosave with debounce and the practice needed to use these concepts confidently in real projects.
- Typeahead search with debounce and switchMap
- Cancelling stale requests
- Autosave with debounce
- Form value streams
- Cross-field reactive validation
- Polling with interval and switchMap
- Stopping polling on inactivity
- Infinite scroll streams
- Pagination with scan
- Drag and drop with mouse event streams
- Double-click and gesture detection
- WebSocket reconnection logic
- Server-sent events as streams
- Progress reporting
- Optimistic UI updates
- Caching with shareReplay and invalidation
- Coordinating multiple loading indicators
- Combining route params with data loads
- Undo and redo with scan
- State machines with streams
- Rate limiting user actions
- Choosing streams or promises per case
Chapter 10Testing, Debugging and Project Work
Testing, Debugging and Project Work
This chapter focuses on Why streams need dedicated testing, Testing with subscribe assertions, The TestScheduler and the practice needed to use these concepts confidently in real projects.
- Why streams need dedicated testing
- Testing with subscribe assertions
- The TestScheduler
- Marble syntax for tests
- cold and hot helpers
- expectObservable
- expectSubscriptions
- Testing time-based operators
- Testing error paths with marbles
- Mocking services that return observables
- Testing custom operators
- Common testing pitfalls
- Debugging with tap and logging
- RxJS DevTools and visualisation
- Finding memory leaks from subscriptions
- Detecting unsubscribed streams
- Performance of long operator chains
- Migrating deprecated operators
- Project: designing the stream architecture
- Project: implementing the data flows
- Project: error handling and resilience
- Project: tests and final walkthrough
Reactive Foundations
This chapter focuses on What reactive programming means, Push against pull data models, Promises compared with observables and the practice needed to use these concepts confidently in real projects.
- What reactive programming means
- Push against pull data models
- Promises compared with observables
- Single values against streams
- Where RxJS is used in practice
- Installing and importing RxJS
- The Observable type
- The observer contract
- next, error and complete
- Subscribing to an observable
- The Subscription object
- Unsubscribing and teardown
- Cold observables
- Hot observables
- Making a cold observable hot
- Unicast against multicast
- Synchronous and asynchronous emissions
- Marble diagram notation
- Reading marble diagrams
- The pipeable operator model
- The pipe function
- A first end-to-end stream
Upskilling & Induction Programs
Corporate RxJS Course
Corporate RxJS course delivery makes reactive code something your team can read and debug: observables, operators, subjects, error handling and subscription management, taught against the asynchronous problems your applications actually hit. On-site in Chennai or live online. The pace is set by your developers.
Industry-Relevant RxJS Skills
Observables and operators, subjects, flattening strategies, error handling, retries, schedulers and subscription lifecycles.
AI-Enabled Learning
Work effectively with Claude and AI development tools while human reasoning, engineering judgement and ownership stay at the centre of every RxJS decision.
Induction & Upskilling Programs
Structured learning paths for new hires, freshers and experienced developers adopting or strengthening RxJS skills.
Hands-On Reactive Workflows
Compose streams for search, polling and cancellation, handle errors and retries, then test and debug marble by marble.
Customized Corporate Programs
Align training with your roles, technology stack, delivery timeline, live projects and organisational requirements.
AI-Evaluated Skill Development
Evaluate practical progress through AI-assisted assessments that identify strengths, skill gaps and areas for improvement.
Stream. Combine. Cancel.
RxJS Training Skills You Gain
Fifteen capabilities you leave with — stream thinking, the core operator set, flattening strategies, cancellation and marble testing.
Thinking in Streams
Model events, requests and user input as observable streams instead of scattered callbacks and flags.
Observables & Subscriptions
Understand cold and hot observables, subscription lifetimes, and what actually starts and stops the work.
Transformation Operators
Shape streams with map, filter, scan and the rest of the core operator set, composed as a readable pipeline.
Flattening Strategies
Choose between switchMap, mergeMap, concatMap and exhaustMap and explain the difference in behaviour.
Combining Streams
Join sources with combineLatest, withLatestFrom, forkJoin and zip without creating hidden ordering bugs.
Subjects & Multicasting
Use Subject, BehaviorSubject and share to multicast a stream to several consumers safely.
Error Handling & Retries
Recover from failures with catchError, retry and backoff so a stream fails in a way the interface can present.
Timing & Rate Control
Apply debounce, throttle, auditTime and distinctUntilChanged to typeahead, scroll and polling work.
Cancellation & Cleanup
Cancel in-flight work with takeUntil and unsubscribe patterns so streams never outlive the view that created them.
Debugging Streams
Instrument pipelines with tap and DevTools to see what a stream is actually emitting and when.
Marble Testing
Test asynchronous behaviour deterministically with marble diagrams and the TestScheduler.
Reactive HTTP & WebSockets
Drive API calls, polling and live socket data reactively, with the cancellation each case needs.
Reactive State Patterns
Build small reactive stores from streams, and connect them to Angular signals or React state cleanly.
Custom Operators
Extract repeated pipelines into custom operators that are named for the behaviour they encapsulate.
AI-Assisted Development
Use Claude and Claude Code to reason about and review stream logic while you keep the reactive design.
How the verification works
How you verify your RxJS skills independently
Most training providers set their own test and mark their own paper. We do not. At the end of each stage of the RxJS Course you check your own readiness using your own ChatGPT, Claude, Gemini or other AI account. Wisen does not write the questions, does not see your answers, and does not record your score.
The reasoning is straightforward. A score we control proves very little — to an employer, or to you. A score produced by a tool we have no influence over is worth something. You ask the AI to test you on RxJS, it decides what to ask, and the result belongs to you alone.
Seventy per cent is the mark we treat as ready. Score seventy or above and you move on to the next stage. Score below it and we work through the gap with you: identify what was missed, teach it again, practise it, then go back to the AI and check. You repeat that loop as many times as it takes.
In short
- You use your own AI account, not one of ours.
- We do not write the questions and cannot influence them.
- Your score stays private — we never see it.
- Below seventy per cent, we work through the gap with you and you verify again.
Our Unique Promise
Independent AIVerification Checkpoint
You learn RxJS Course. AI verifies. Wisen helps you grow beyond 70%.
Use ChatGPT, Claude, or another AI tool to validate your RxJS Course readiness.
It is your learning journey. Go at your pace.
Every step you take today builds your tomorrow.
Our mission is your growth, always.
Placement Assistance
Career Support You Can Count On
RxJS training for developers tired of guessing which operator to use. We make no job guarantee at all — we make you someone worth interviewing.
- 01
Gain 2+ Years of Professional Knowledge
Operator choice, subscription management and debugging a stream that fires twice are the things that take most developers two years to get right. We go straight at them.
- 02
Resume / Biodata Support
Get expert guidance to build a strong, professional resume that highlights your skills, projects and achievements.
- 03
Portfolio Development
Build real-world projects and a strong portfolio that demonstrates your practical skills to potential employers.
- 04
Interview Preparation
Reactive questions are marble-diagram questions. We practise drawing the stream, naming the operator and explaining the timing out loud, which is exactly how they are asked.
- 05
Job Search Guidance
RxJS depth is a differentiator inside Angular and Node roles rather than a title. We help you find those roles and lead with the skill where it counts.
- 06
Placement Assistance
We assist you in identifying relevant opportunities and connecting with potential employers.
- 07
Independent AI Verification Checkpoint
Your learning, projects and skills are verified by our Independent AI Verification System to ensure objective and unbiased evaluation.
- 08
Future-Ready Knowledge
Reactive thinking outlives any one library. What you learn here transfers to signals, streams and whatever the next abstraction over asynchronous data turns out to be.
Our Commitment
We do not guarantee employment and never structure the course as if we did. Your success rests on your practice, assessments, interviews and employer needs. We stay available at every step.
Stream. Practice. Master RxJS.
Reactive Programming Course Materials
This reactive programming course is supported by material that makes stream behaviour visible. Notes explain operators and subscription lifetimes with diagrams; lab activities build a typeahead with cancellation and retries; and exercises ask you to fix pipelines that leak, duplicate requests or emit in the wrong order. Everything is authored in-house and practised against real asynchronous work. All original work.
What You Will Receive
RxJS Notes & Explanations
Explanations of observables, operators, flattening strategies, subjects and cancellation, written for practising developers rather than copied from documentation.
Guided Lab Activities
Labs that carry one change through planning, implementation and verification — a typeahead with debouncing, cancellation and retry among them.
Hands-On Exercises
Independent tasks on fixing leaks, duplicated requests and out-of-order emissions, worked without a walkthrough to lean on.
Worked Walkthroughs
Recorded sessions showing project setup, the change itself, and the checks that prove it works.
Progressive Learning Path
A route from the fundamentals to reactive state and marble-tested asynchronous logic, in the order the live sessions follow.
Revision & Reference Sheets
Compact references for operator selection, marble syntax and cleanup patterns, plus the review habits that keep AI-assisted work safe.
What Makes Our RxJS Learning Materials Different?
27+ Years of Experience
Authored by trainers who weigh every RxJS decision against decades of delivered software.
Human-Authored Content
Written by trainers who work with RxJS daily, then reviewed line by line.
Original Learning Materials
Created in-house, not assembled from documentation or shared prompt collections.
Practice First
Every technique is applied to a real RxJS task and its result inspected.
Continuously Refined
Revised as RxJS and developer tooling move, so sessions reflect what works this month.
Review Discipline Built In
Materials teach reading the diff and testing the change, not accepting output on trust.
Plan. Stream. Verify.
RxJS Course Duration & Batch Timings
RxJS Course from Wisen IT Solutions, Chennai runs live in two paces over 60 Hrs of instructor-led training. The lecture and practical time is split 50 : 50, with the practical half weighted towards composing streams and proving their timing with marble tests.
Total Learning Hours
60 Hrs
Lecture : Practical
50 : 50
Batches
Weekday & Weekend
- Instructor-led sessions
- Guided lab activities
- Hands-on RxJS practice
- Reviewed project work
Normal Track
2.5 Hours / Session
24 sessions · about 5 weeks
A steady pace for developers taking RxJS training alongside a full working day.
- Working Developers
- College Students
- Team Leads
- Weekend Batches
Fast Track
5 Hours / Session
12 sessions · about 3 weeks
A concentrated schedule through the same RxJS syllabus for learners free on weekdays.
- Full-Time Learners
- Job Seekers
- Fresh Graduates
- Career Switchers
What Every Seat Includes
- Live instructor-led sessions
- Hands-on RxJS coding
- Guided lab activities
- Independent exercises
- AI-assisted learning
- Code review and feedback
- Doubt clarification
- Certificate on completion
Same Syllabus · Same Labs · Same Evaluation · Same Outcome
Whichever batch of the RxJS Course you join, the syllabus, lab activities, exercises and evaluation are identical. Only the pace differs, so pick the track that fits the time you can genuinely give it each week.
Live online, worldwide
Join RxJS Course from anywhere in the world
Every session is taught live by a practising engineer — never a pre-recorded video. Batches run to Indian Standard Time, and the timing is adjusted to suit your time zone wherever you are.
Live, not recorded
You write code during the session, ask questions as they come up, and have that code reviewed.
Your time zone, any country
Weekday and weekend slots in IST. If none of them suit where you live, we schedule a batch that does.
Pay from outside India
International debit and credit cards, PayPal and direct bank transfer are all accepted.
Balanced Learning. Live Streams. Career-Ready Skills.
RxJS Lecture-Practical Ratio
RxJS is a practice, not a subject to read about. The RxJS Course is delivered on a 50 : 50 lecture-practical ratio, so every concept is applied in the same session it is explained, on code that behaves like the code you will be paid to write.
Sessions are spent composing streams and proving their timing with marble tests — which is what delivery work and technical interviews actually ask for, rather than a description of it.
50%Theory
50%Practical
50% Theory
Where each RxJS idea comes from, and when it is the right one to reach for.
- Reactive Foundations
- Transformation Operators
- Combination Operators
- Subjects and Multicasting
- Schedulers, Concurrency and Utility
- Testing, Debugging and Project Work
50% Practical
What you do with it, in the same session, on code that behaves like production.
- Composing pipelines operator by operator
- Building a typeahead with cancellation
- Fixing a leak with takeUntil and cleanup
- Choosing a flattening operator and proving it
- Writing marble tests on the TestScheduler
- Instrumenting a stream to see what it emits
Why a 50 : 50 Split Works for RxJS
See It Work First
Each idea is demonstrated running before you are asked to build with it.
Build It Immediately
Every concept becomes RxJS code you write while it is still fresh.
Work on Real Code
Practice happens on realistic repositories, not on disposable snippets.
Fail Where It Is Safe
Break it in the room, where a trainer can explain what actually went wrong.
Prove the Skill
Leave able to demonstrate the work, not only to talk about it.
Our Learning Philosophy
Every RxJS concept is followed by something you build yourself.
Clear Entry Bar. No Guesswork. Career-Ready Start.
RxJS Course Prerequisites
This RxJS Course assumes no reactive programming experience beyond the language prerequisite below. Observables, operators, subjects, schedulers and error handling are introduced from the first session.
The RxJS Course is delivered live online and in Chennai, so everyone starts the same exercises from the same baseline.
MandatoryJavaScript Foundation
- JavaScript is a mandatory prerequisite — begin with the JavaScript Course
- Functions, arrays, objects and destructuring
- Promises and async/await in everyday use
- Callbacks and event handlers in the browser
EngineeringDiscipline
- Willingness to review every change you write
- Care with credentials and private repositories
- Habit of describing a defect precisely
- Commitment to the hands-on RxJS Course builds
RxJS WorkspaceSetup
- A laptop with a stable internet connection
- Node.js and npm — setup guidance provided
- VS Code plus a working terminal
- A modern browser with developer tools
Who Can Join?
- Students & Graduates
- JavaScript & Angular Developers
- Tech Leads & Architects
- Teams taming asynchronous code with streams
The Streams. The Operators. The Toolchain.
RxJS Course Tools & Technologies
The RxJS Course is taught inside the tools the work actually happens in. RxJS is taught as streams you can draw — marble diagrams on the board, the same sequences written in TypeScript and then asserted in marble tests.
You leave able to pick the right operator instead of nesting subscriptions. Every tool listed below is used in the sessions rather than only named in them.
Reactive Core
- Observables
- Subscriptions
- Creation Operators
- of / from / interval
- Unsubscription
- Cold vs Hot
Operators
- map & switchMap
- mergeMap & concatMap
- debounceTime
- filter & distinct
- combineLatest
- scan & reduce
Subjects & Resilience
- Subject & BehaviorSubject
- ReplaySubject
- catchError & retry
- share & shareReplay
- Multicasting
- Schedulers
Tooling & Quality
- TypeScript
- Angular CLI
- Marble Testing
- RxJS DevTools
- ESLint & Prettier
- VS Code
Learning Outcome
You finish the RxJS Course able to compose streams with the right operator instead of nested subscriptions — through project work you can defend in review.
- Compose Streams
- Choose the Operator
- Handle Failure
- Test With Marbles
Primary Sources
RxJS Course Official References
Operator semantics are precise and worth checking at the source; the language reference covers the asynchronous model underneath them.
- RxJS — Official documentation
The library’s reference for observables, operators and subscription management.
- MDN Web Docs — JavaScript
Mozilla’s language reference for the syntax, the built-ins and the runtime semantics taught in the syllabus.
Got Questions - Quick Answers
Frequently asked questions
Is there real hiring demand for the RxJS Course skills in Chennai?
Product companies, global capability centres and services firms in Chennai all run teams on this stack, which keeps steady demand behind the RxJS Course. Because the Reactive Programming Course is used for new builds and for long-lived applications alike, that demand spans startups and established engineering organisations.
Can freshers and non-IT graduates join Reactive Programming Training?
Yes. Freshers and graduates from non-IT streams join regularly, and Reactive Programming Training starts from the fundamentals before moving into advanced work. If your programming basics are thin we will say so before you enrol, and suggest the order in which to take RxJS Training and its prerequisites.
What is the refund policy if I enrol in the RxJS Course?
We run a one-week evaluation instead of a one-hour demo class. A ₹2,000 registration fee reserves your seat in the RxJS Course; attend the first week of live sessions and, if the training is not the right fit, that registration fee is refunded in full. If you register but cannot attend, it converts to Training Credit valid for 12 months. Once the course fee is paid, Reactive Programming Training fees are transferable once, within a month, if you leave before two weeks, and are neither refundable nor transferable after two weeks of attendance.
What placement support do I get with RxJS Training?
We do not promise a job, and you should be wary of anyone who does. What RxJS Training includes is preparation: we help you prepare your biodata, build a portfolio from work you have actually done, and identify the knowledge gaps that would cost you an interview. That review covers the the RxJS Course skills interviewers ask about today and the ones worth learning next, so you can keep preparing after the course ends.
- 27+
- Years of training
Delivering technical training from Chennai since 1996. - 17,700+
- Learners empowered through training
Corporate teams, IT working professionals, career switchers and students. - 2,700+
- Happy students / year
Learners completing our programmes every year. - 30+
- Corporate clients
Product companies, service firms and startups.
Corporate training clients
Teams that train with Wisen IT Solutions, Chennai, India
Engineering teams across product companies, IT services firms and startups run their JavaScript, Angular, React and Next.js upskilling and induction programs with us.
Altimetrik 
Aparajitha Corporate Services 
Caresoft 
Dzine Hub 
Firstsource 
Gigamon 
Helios and Matheson 
NextGen Healthcare 
Perpetuuiti Technosoft 
R Systems 
SRM Institute of Science and Technology 
Temenos 
The Hindu 
Tamil Nadu Electricity Board 
WABCO
Build JavaScript for the AI-era
Plan your JavaScript training with Wisen IT Solutions, India
Tell us where you are today — a beginner, a working developer, or a team with a delivery deadline — and we will map the right course, format and schedule.
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