Java · Node · Python · Go · Angular · React · AWS

Systems designed, built and modernised — at a fixed price.

New systems, and the ones that have outlived their stack. Architecture, build, migration — delivered as bounded modules, each with its own price, date and written acceptance criteria. No hourly billing, no scope creep, no overrun. The work decides the stack, not me.

Book a 20-minute call See pricing
15+ yearsArchitecture and delivery
Fixed priceQuoted before you commit
Any stackBackend, frontend and cloud

What I take on

The enterprise stack built around 2015 — a JVM or .NET backend, an AngularJS front end, on-prem deployment — reached end of life on all three layers at once. Most contractors can fix one. I quote the whole thing, so the integration risk stays with me instead of with you.

Fifteen years of this across healthcare document systems, financial and billing platforms, building operations, automation and integration work — so I usually understand the domain before I open the codebase, which is where this kind of work tends to go wrong.

Architecture

New systems, designed and built

Greenfield work where the scope is defined: an architecture, a sequenced plan, then the build in modules. Most useful where the system has to be right the first time rather than iterated into shape.

  • Architecture review and target design
  • Event-driven and service decomposition
  • Multi-tenant platforms, SSO, operations tooling
  • Delivered module by module, priced before you commit
Backend

Framework and runtime upgrades

Out of support and blocking your security review. Mechanical work that touches every file — which is exactly the kind that overruns when it is billed hourly.

  • Spring Boot 2 → 3, Java 8/11 → 21
  • Node, Python and Go version migrations
  • Dependency and CVE remediation
  • Test suite green before handover
Frontend

Front-end rewrites

AngularJS has had no security patches since January 2022. Migrated incrementally, screen group by screen group — nothing goes dark mid-way.

  • AngularJS → Angular, component by component
  • Angular and React version upgrades
  • Server-rendered templates → SPA
Cloud

Cloud migration

WebLogic and Oracle licensing commonly runs $50k+ a year. The migration usually pays for itself inside twelve months.

  • Terraform infrastructure as code
  • Containerization, ECS / EKS / AKS
  • CI/CD pipeline and staging mirror
  • Cutover runbook for your team
Performance

Slow endpoints, fixed to a number

Three named endpoints to an agreed p95, measured before and after on staging. Half the fee is contingent on hitting the target.

  • N+1 queries, missing indexes
  • In-memory joins that belong in SQL
  • Serial calls that should run parallel
Architecture

A plan before anyone writes code

A week reading what you already have, then a written roadmap: what to change, in what order, and what each piece costs. No code, no commitment beyond the week, and the document is yours whether or not I build any of it.

  • Current state, honestly described
  • Target architecture and the steps between
  • Each module scoped and priced, so you can stop at any point

How it works

Every engagement starts with a paid assessment. You get a fixed price on every module before you commit to any of them — and the assessment is useful on its own even if you stop there.

  1. Paid assessment

    Three to five days. I read the codebase and return every blocker, the effort behind each one, a risk register, and a fixed price per module.

  2. You pick the modules

    Take all of them, some of them, or none. Each module carries itemized deliverables, objective acceptance criteria and a delivery date.

  3. Delivery in milestones

    Short gates, not quarterly ones. You review working code against the written criteria at every milestone, so nothing runs for months before you see it.

  4. Handover

    Tests green, documentation written, code transferred. For cloud work, your team runs the production cutover from my runbook, with me on the call.

Pricing

Published, because a number you can plan against is the point. Everything is fixed-price — if the work takes longer than I estimated, that is my problem and not your budget's.

EngagementScopePriceTerms
Assessment3–5 days. Written report, blockers, effort, fixed module quotes$900 – $2,500100% upfront
Architecture roadmap1 week. Current state, target architecture, sequenced plan. No code$2,500 – $5,000100% upfront
Performance2–3 weeks. Three endpoints to an agreed p95$6,000 – $15,00050% up, 50% on hitting the number
Single module2–4 weeks. One bounded slice of one layer$5,000 – $12,00050% / 50%
Multi-module5–8 weeks. Two layers$15,000 – $28,000Milestone-gated
Full program10–14 weeks. Backend, frontend and cloud$30,000 – $55,000Milestone-gated

Payment due on invoice; work begins on receipt of funds. Intellectual property transfers on final payment. Two review rounds are included in every module — anything outside the written acceptance criteria is a change order with its own price and date.

Selected work

Fifteen years of enterprise delivery. Client work is described without naming the client; the reference implementation is public and runnable.

Live demo

Building operations console

Floor plans with devices plotted by position and coloured by status, per-floor alert handling, deviation from setpoint, and estate demand. A fault is located, not just listed.

  • Angular · standalone components and signals, no NgModules
  • 142 kB bundle, no charting library
  • Open the demo  ·  Source
Live demo

Trade storefront

A supplier catalogue for architectural lighting. Specification filtering on colour temperature, beam angle and ingress rating, with trade accounts, cart, checkout and order history.

  • React 19 · TypeScript · Vite · Tailwind
  • Colour temperature rendered as colour; each product drawn in section from its own data
  • Open the demo  ·  Source
Open source

Event-driven telemetry pipeline

A runnable reference implementation of the building-telemetry architecture I use: ingest, windowed anomaly detection, and command dispatch over Kafka.

  • TypeScript · Fastify · Kafka · MongoDB
  • Detection rules as a pure, unit-tested module
  • Simulator with realistic occupancy curves and seeded faults
  • Repository, CI-verified
Open source

O&M handover gap report

Reads a folder of building-services handover documents and reports what is missing — the assets with no commissioning certificate, the certificates for plant that was never in the register, and the scans nobody can read.

  • Python · pdfplumber · no cloud, no API key
  • Collapses the five ways one asset tag gets written, so it never reports a certificate missing that is sitting in the folder
  • Unreadable scans are cross-referenced against the gaps they may be hiding
  • Repository, CI-verified
Case study

Workflow orchestration platform

A configurable engine for construction project delivery — pipelines defined as data, so routing changes without a deployment. Included extracting a 3,100-line route file into a service layer behind repository interfaces.

  • Fastify · TypeScript · MongoDB · Socket.IO · Kafka
  • 913 source files · 99 test files
  • Multi-tenant isolation enforced in middleware
Case study

Building management platform

Event-driven monitoring and control across multiple office campuses — HVAC, electrical metering and DC power — decomposed so ingestion throughput and analytics load scale independently.

  • Six Kafka microservices · 438 source files
  • Telemetry, anomaly detection, scheduling, device registry
Case study

Financial modelling engine

IRR modelling for commercial property deals, replacing the spreadsheets an investment team had been pricing deals with. Capex and opex drivers held as versioned data rather than cells.

  • Spring Boot 3.5 · Java 21 · Spring Data MongoDB
  • React 18 front end for scenario comparison

Start with an assessment

Tell me what you are running and what is blocking you. I reply within one business day with scope and a price, or tell you straight away if it isn't a fit.

Or email directly: ashish@ashishaggarwal168.com
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