// portfolio — the whole pack
Nikhil Sahu.
Software Engineer — Backend, Cloud & Distributed Systems
I build backend systems, cloud infrastructure and AI-powered products that scale, ship, and stay up. Terraform-first AWS, FastAPI/Go services, LGTM observability and production RAG are my daily tools.
Mumbai, Maharashtra, India (IST, UTC+5:30) · open to remote
photo: placeholder// 01 — experience
Three teams, three stacks, one habit: own it end to end.
Software Engineer
2025-11 → presentRaghuvarTech (Raghuvar IT Solutions LLP) · Ranchi, Jharkhand
Own infrastructure, CI/CD and observability for a multi-service platform; lead architecture reviews across backend, infra and agentic-AI systems.
- Own infra provisioning across dev/staging/prod with Terraform (VPC, EC2, RDS, IAM) as Infrastructure-as-Code; GitHub Actions pipelines enforce plan-before-apply, drift detection, and SSM/OIDC-backed secrets with zero long-lived credentials.
- Architected infra-ops, a centralized multi-environment IaC platform: S3 remote state, DynamoDB state locking, reusable Terraform modules (networking/compute/storage/IAM) and Ansible roles for PostgreSQL/PostGIS, Nginx+Certbot and PM2 deploys.
- Built lgtm-sidecar, a resource-capped observability stack (Grafana Alloy, Loki, Tempo, Prometheus, Pyroscope, Alertmanager) as a decoupled EC2 sidecar with distributed tracing and rate-capped tail sampling.
- Lead architecture reviews and cross-functional delivery across backend microservices, infrastructure, and RAG & agentic-AI systems; driving adoption of Kubernetes, Helm, ArgoCD (GitOps), Kustomize, Istio and Vault/External Secrets Operator.
- Standardized CI/CD across all services with environment-gated promotions and health-check-triggered rollbacks, cutting deployment cycles by 40%.
TerraformAnsibleAWSGitHub ActionsKubernetesArgoCDGrafanaLokiTempoPrometheusFastAPIPostgreSQLSoftware Development Engineer
2025-06 → 2025-10InkHub.in / BRMH.ai · Ranchi, Jharkhand
Built an AI-powered backend-as-a-service that generates full-stack e-commerce apps from prompts, and re-architected its AWS footprint.
- Built an AI-powered BaaS platform generating full-stack e-commerce apps (RESTful APIs, DB schemas, frontend) from prompts, deployed on AWS (EC2, ECS, Lambda, Step Functions, DynamoDB, Valkey, CloudWatch).
- Re-architected monolithic AWS infra into event-driven, containerized microservices, cutting monthly cloud spend by 76% with a zero-downtime migration.
- Owned observability and on-call readiness with CloudWatch alarms and structured logging, reducing mean-time-to-detect and accelerating root-cause resolution.
AWS ECSLambdaStep FunctionsDynamoDBValkeyCloudWatchNode.jsLLM integrationSoftware Development Engineer (Remote)
2024-11 → 2025-05EatTogether & Co. · Seattle, WA, USA (remote)
Backend engineer on a US food-tech team: real-time pricing, monolith-to-microservices refactor, cross-timezone agile delivery.
- Built a sub-100ms dynamic surge-pricing engine that personalizes user rates from real-time availability, spend history and geolocation.
- Refactored a monolith into event-driven microservices with async communication, improving isolation, independent deployability and integration with dependent systems.
- Collaborated cross-timezone with a distributed US team in an agile workflow: sprint planning, code review and incremental rollout of API and pricing changes.
Node.jsPostgreSQLRedisEvent-driven architectureREST APIs
// 02 — projects
Things I built and run.
CaseCloud
AI legal case management - multi-tenant SaaS with RAG over an 80M+ judgment corpus
- Multi-tenant SaaS with schema-per-tenant isolation (RLS, dynamic search_path) across cases, clients, proceedings, payments, cause lists and reminders under unified RBAC.
- RAG pipeline over a private legal corpus: Playwright court-portal ingestion, PDF parsing, Milvus vector indexing, hybrid dense+sparse retrieval with RRF reranking and source citations.
- Agentic drafting system grounding Gemini over 80M+ judgments and 6K+ legal templates with placeholder canonicalization, delivering jurisdiction-aware structured drafts from natural-language queries.
FastAPIPostgreSQLMilvusRedisRAGNext.jsAWS
Vedico
Telecom infra & realtime fleet tracking - Go WebSocket fan-out, geofencing, SLA escalation
- Decoupled Go realtime microservice (goroutine event loop, sync.RWMutex-guarded connection maps, channel multiplexing) delivering sub-millisecond circle-scoped WebSocket broadcast of GPS telemetry to a NOC dashboard.
- Haversine spatial engine with a 5-minute grace window for offline mobile flushes, plus a theft/proximity anomaly detector combining 50m geofencing, PostgreSQL FOR UPDATE locking and active work-order context.
- 4-tier automated SLA escalation state machine (Technician → Supervisor → Cluster Incharge → Manager) with FCM push, transient-failure backoff and hierarchical RBAC scoping.
GoFastAPIPostgreSQLPostGISFlutterNext.js
infra-ops
Multi-environment AWS IaC platform - Terraform + Ansible + GitOps-style CI/CD
- Centralized Terraform + Ansible repo provisioning dev/staging/prod: VPC/subnet/SG networking, EC2, S3 and least-privilege IAM via reusable, composable modules.
- GitOps-style CI/CD: PR-triggered terraform plan, environment-gated auto-apply to dev with manual approval gates for staging/prod, nightly drift detection that opens GitHub issues on divergence.
- Hardened provisioning: OIDC-based GitHub Actions auth (no long-lived keys), IMDSv2 enforcement, UFW + fail2ban, encrypted, versioned, DynamoDB-locked state.
TerraformAnsibleGitHub ActionsAWS
lgtm-sidecar
Open-source observability hub - LGTM stack + Pyroscope as a resource-capped sidecar
- Production-grade, resource-optimized observability sidecar on the LGTM stack plus Pyroscope and Alertmanager, fronted by Nginx/Certbot TLS and decoupled from app hosts via a lightweight Edge Alloy agent.
- OpenTelemetry pipelines with W3C TraceID correlation across FastAPI and Next.js services; tenant/office ids flow through span baggage into structured metadata rather than high-cardinality labels.
- SRE-grade policy: rate-capped tail sampling, S3-backed Loki/Tempo via IAM role, Prometheus/Loki-ruler → Alertmanager (Slack + email), memory-limited Alloy pipelines.
Grafana AlloyLokiTempoPrometheusOpenTelemetryDocker
Immigration Copilot
Agentic form automation - LLM agents fill I-485 / DS-160 via a Playwright CDP harness
- LLM agents autonomously navigate and populate immigration forms via a Playwright CDP browser harness with mid-session decision handling and form-state recovery.
- LangChain pipeline extracts structured applicant data from noisy documents via schema mapping and field-level conflict resolution: 90% reduction in manual entry.
ElectronPlaywright CDPLangChain
// 03 — skills, with receipts
The toolbox, and the proof.
Every tool links to the shipped systems that used it. Hover one to see how I use it and what it was built alongside.
daily driver regular working knowledgehover to preview · click to pin · 31 tools · 7 shipped systems
Infra & Cloud
Terraform
Daily driversince 2024 · 2 yrs
Multi-environment IaC: versioned modules, S3 + DynamoDB state, plan-before-apply in CI and nightly drift jobs that open issues.
Receipts
- infra-opsReplaced click-ops and shared credentials with a single IaC repository: reusable Terraform modules, Ansible roles, plan-before-apply pipelines, OIDC auth and nightly drift detection.
- lgtm-sidecarThe full LGTM stack plus profiling and alerting, packaged as a decoupled sidecar that never starves the applications it watches, with distributed tracing across FastAPI and Next.js.
Where
RaghuvarTech
Shipped alongside
// 04 — journey
How I got here.
2022
Started BCA at St. Xavier's, Ranchi
First production code: a college fest site that survived launch day.
2024-11
EatTogether & Co. (remote, Seattle)
Sub-100ms surge pricing and the first monolith I pulled apart.
2025-06
InkHub / BRMH.ai
Prompt-to-app BaaS on AWS; cut the cloud bill by 76%.
2025-07
Graduated BCA · CGPA 8.5
2025-08
M.S. CS & Data Science, IIT Patna
Distributed systems and ML, part-time alongside work.
2025-11
RaghuvarTech
Own infra, CI/CD and observability; lead architecture reviews.
2026-06
AWS Solutions Architect – Associate
education
M.S. in Computer Science & Data Science (CSDA)
Indian Institute of Technology Patna · 2025–present
Bachelor of Computer Applications · CGPA 8.5/10
St. Xavier's College, Ranchi · 2022–2025-07
certifications
AWS Certified Solutions Architect – Associate (SAA-C03)
Amazon Web Services · 2026-06
on the shelf
- Building Microservices (2nd edition) · Sam Newman
- Site Reliability Engineering: How Google Runs Production Systems · Betsy Beyer, Chris Jones, Jennifer Petoff, Niall Richard Murphy
- Terraform: Up & Running (3rd edition) · Yevgeniy Brikman
- Designing Data-Intensive Applications · Martin Kleppmann
// 05 — case studies
The long versions.
// 06 — writing
Recent notes.
012 min
Advanced RAG Architecture: Graph, Vector, Redis, and PostgreSQL
Combining Graph databases, Vector databases with Reciprocal Rank Fusion (RRF), Redis caching, and PostgreSQL to build a state-of-the-art RAG system.
ragaidatabasesvector db
021 min
The Evolution of AI: From RAGs to Autonomous Agents
Exploring the transition from Retrieval-Augmented Generation (RAG) to fully autonomous AI agents capable of complex reasoning.
aiagentsragllms
032 min
Building a Digital Garden with Next.js and Obsidian
How this site turns an Obsidian vault into a blog, a knowledge graph and an AI knowledge base, and a tour of everything a note can contain.
next.jsobsidiandigital gardenmarkdown
// let's work together
Book a 15-min call
Pick a time that fits you, or just
email me at hi@nikhilsahu.dev