01Systems in motion

Viveak Vadivelkarasan

Tech Lead · Distributed Systems · External APIs

Engineering.In motion.

I build reliable platforms, lead engineering teams, and take products from idea to production.

Explore my work Download CV Get in touch

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London, UKScroll to explore

02Complex environments

Built tokeep moving.

From an event platform carrying around a million events a day to migrations with zero customer-visible disruption, I turn complex systems into reliable, scalable platforms.

03Evidence at scale

~1M

events per day

through the event-driven delivery service I designed and built on my latest project.

Read the case study

Leading 9 engineers.

Technical lead across multiple parallel workstreams on my latest project, working closely with product, delivery and the technical architect, and owning architecture and engineering standards.

See the role

04Selected work · Latest project · Tech Lead, External APIs

Designing delivery for ~1Mevents a day.

I lead a team of 9 engineers across multiple parallel workstreams, working closely with product, delivery and the technical architect, and I designed and built the event-driven webhook delivery service behind every external client integration.

~1Mevents per day

AWS EventBridge
BullMQ
Redis
PostgreSQL
EKS
HMAC
Datadog

Read the case study

Conceptual illustration. Not a diagram of any employer's systems.

Conceptual illustration. It does not depict the client's architecture.

05Dyson · via Deloitte Digital · Lead Engineer

Changing the platform behinda 300+ engineer organisation.

As Lead Engineer on the Deloitte Digital programme, I led the EC2-to-Kubernetes migration on AWS and built the automated UAT and performance environments around it.

300+engineers in the organisation, Jun 2018 - May 2020

AWS
Kubernetes
EC2
AEM

Read the case study

06LEGO · via Deloitte Digital · Lead Engineer

A platform migration.Zero customer-visible disruption.

As Lead Engineer on the Deloitte Digital programme, I led a team of four engineers migrating LEGO's communication channels from Oracle Crowdtwist to Salesforce Marketing Cloud, and built the AWS integrations underpinning the new marketing pipeline.

0customer-visible disruptions

Salesforce Marketing Cloud
Oracle Crowdtwist
AWS

Read the case study

Conceptual illustration. Not a record of the programme's architecture.

Separate engagement · Full-Stack Developer, LEGO.com · via Deloitte Digital

Jun 2020 - Jun 2021

~30% fewer customer-service contacts.

Designed and shipped the AWS-driven automated self-returns journey on LEGO.com, cutting customer-service contact volume by ~30%.

A different engagement from the marketing-platform migration above; it is not an outcome of that migration.

See the engagement

07From platforms to products · AadhiPixels

From the first idea.To the product in your hand.

Independent product studio where I identify product opportunities, then design, architect, build, deploy and operate the software myself, alongside smaller experiments taken from concept to working product.

Explore the products Try the walkthroughs

Find local help

Sample marketplace

Service

CleaningPlumbingElectricalGardeningHandyman

Postcode area

E2SE1N1SW4

3 sample providers in E2

£60 to £95 call-out

Northlock Plumbing
4.9(211)From £65
Replies in about 1 hour
Request
Copperline Plumbing & Heating
4.7(89)From £60
Replies in about 2 hours
Request
Tapwright & Sons
4.6(54)From £70
Replies same day
Request

Ratings, reviews and prices are sample data.

Your booking

Request a booking to follow its status here.

TheCocoCard · customer card

Find local help

Sample marketplace

Service

CleaningPlumbingElectricalGardeningHandyman

Postcode area

E2SE1N1SW4

3 sample providers in E2

£60 to £95 call-out

Northlock Plumbing
4.9(211)From £65
Replies in about 1 hour
Request
Copperline Plumbing & Heating
4.7(89)From £60
Replies in about 2 hours
Request
Tapwright & Sons
4.6(54)From £70
Replies same day
Request

Ratings, reviews and prices are sample data.

Your booking

Request a booking to follow its status here.

Fixabee · local services

Conceptual walkthrough with synthetic data. Sample business rules are illustrative and not confirmed live-product behaviour. Nothing here creates real accounts, payments, payouts or bookings.

TheCocoCard
Digital loyalty for local businesses.
Walkthrough Visit thecococard.com
Fixabee
Local services. Sorted.
Walkthrough Visit fixabee.com

08Live simulation · Show the engineering

Break the system.See how it recovers.

An interactive, deterministic simulation of a resilient webhook delivery pipeline: retries with bounded backoff, per-subscription circuit breakers, rate limits, a dead-letter queue with replay, and HMAC-signed payloads you can tamper with.

Interactive educational simulation. Synthetic data. Not connected to employer systems.

Try the simulation The platform behind it

Prefer to play it? Throughput is a small 3D arcade game built for this site around the same ideas.

Illustration. The working simulation, with controls and inspectors, is on the lab page.

09The person and the experience

9+ years of platforms,teams and products.

I lead engineering hands-on: on my latest project, a team of 9 across parallel workstreams and the architecture and engineering standards of a platform handling around a million events a day. Before that, seven years at Deloitte Digital, from Engineer to Manager, leading engineering on client programmes for LEGO, Dyson and UK Government.

View the full experience

Selected milestones

2025 - Present
Latest project
Tech Lead, External APIs. Leading 9 engineers across parallel workstreams on a platform handling ~1M events a day.
2018 - 2025
Deloitte Digital
Engineer to Manager, Technology Consulting. Client programmes for LEGO, Dyson and UK Government.
2015 - 2018
Gentrack, Accenture, Tullett Prebon
Software engineering roles, an internship and an industrial placement.
2017
City, University of London
BSc (Hons) Computer Science. AWS Certified Solutions Architect.

10Let's build what's next

Let's buildwhat comes next.

Opportunities, projects and ideas are all welcome. Email is quickest; LinkedIn works too.

Email
viveak.03@gmail.com
LinkedIn
linkedin.com/in/viveakv
CV
Download CV (PDF)
Location
London, UK