Senior Back-End Developer

Kotsrentingprivatelimited; Bengaluru; On-site; INR 1,000,000 - 1,200,000; Full time

Job summary

Kotsrentingprivatelimited is seeking a hands-on Senior Back-End Developer in Bengaluru to design, build, and maintain production-grade server-side code. You will craft Python services (Flask/FastAPI) and REST APIs, write advanced SQL, and own deployments on AWS.

This senior role emphasizes ownership of code through testing, deployment, and production support, with emphasis on performance and reliability. Expect growth in a builder's role with strong teamwork and mentorship.

Qualifications

• 5+ years of hands-on back-end development experience.
• Python—REST APIs with Flask or FastAPI, not just scripting.
• SQL—write advanced queries (PostgreSQL/MySQL) and reason about execution.
• AWS experience deploying and running workloads (ECS/Fargate, Lambda, RDS).
• Testing—write proper unit and integration tests with pytest.

Responsibilities

• Design, build, and maintain Python services and REST APIs.
• Write and optimize complex SQL with multi-table joins, subqueries, and window functions.
• Model relational schemas, design indexes, and tune slow queries.
• Plan and run schema migrations safely on live data.
• Handle authentication, authorization, and API security.
• Build background jobs, queues, and scheduled tasks with reliable retries.
• Write meaningful tests for code and modules.

Skills

Python

Flask

FastAPI

SQL

PostgreSQL

MySQL

AWS

REST APIs

Git workflows

Docker

CI/CD

pytest

Tools

Docker

CI/CD tools

Terraform

AWS CDK

Job description

Wearelookingforahands-onSeniorBack-EndDeveloperwhowritesproduction-gradeserver-sidecode.Youwill

designandbuildtheservicesanddatalayerbehindourapplicationsusingPython,withrelationaldatabases

underneath—alldeployedandoperatedonAWS.

Thisisabuilder'srole,notacoordinator's.YoushouldbecomfortablewritingcomplexSQLbyhand,designingREST

APIsthatotherteamsdependon,reasoningaboutperformanceandfailure,andowningyourcodethroughtesting,

deploymentandproductionsupport.

WhatYou'llDo

• Design,build,andmaintainPython(Flask/FastAPI)servicesandRESTAPIsconsumedbyourfrontendsand
• WriteandoptimiseadvancedSQL—multi-tablejoins,subqueries,CTEs,andwindowfunctions—withoutleaningonanORMtodothethinkingforyou.
• Modelandevolverelationalschemas,designindexes,andtuneslowqueriesusingEXPLAIN/EXPLAINANALYZE.
• Planandrunschemamigrationssafelyagainstlivedata.
• Handleauthentication,authorisation,andthesecurityoftheendpointsyouexpose.
• Buildbackgroundjobs,queues,andscheduledwork,andmakethemsafetoretry.
• Writemeaningfulunitandintegrationtestsforthecodeandmodulesyouship.
• Deploy,monitor,andtroubleshootservicesonAWS,andimprovebuildandreleasepipelines.
• Reviewpeers'code,upholdqualitystandards,andmentorlessexperienceddevelopers.

WhatWe'reLookingFor

Thisisaseniorback-endrole—weexpectdepthinPythonandinrelationaldatabases,andtheabilitytorunwhat

youbuild.

• 5+yearsofrelevant,hands-onback-enddevelopmentexperience.
• Python—solidbackendexperiencebuildingRESTAPIs(FlaskorFastAPI),notjustscripting.
• SQL—abilitytowriteadvancedqueriesfromscratchandreasonabouthowtheyexecute;PostgreSQLand/or
• MySQLinproduction.
• Schemadesign,indexing,andqueryoptimisationonrealdatavolumes.
• AWS—practicalexperiencedeployingandrunningworkloads(e.g.ECS/Fargate,Lambda,RDS).
• APIsecurity—authenticationandauthorisation(JWT,OAuth2)andcommonOWASPrisks.
• Testing—abletowriteproperunitandintegrationtestswithpytest.
• ComfortwithGitworkflows,Docker,andCI/CDpipelines.

ThisRoleIsNotaFitIf

• YouworkonlyinJavaandhavenoPythonexperienceorfamiliarity.
• YourelyentirelyonORMsandcannotwriterawSQLqueriesyourself.
• YourPythonisscriptingandautomationonly—youhaveneverbuiltandrunaproductionservice.
• YouhaveneverworkedwithAWS.(ExperienceonGCPorAzureisaplus,butAWSexperienceisrequired.)
• Youhaveneverwrittentestsforyourowncode.
• Youarelookingforarolethatismostlyfront-endwork.

NicetoHave

• AsyncPython(asyncio)andanunderstandingofconcurrencytrade-offs.
• Queuesandbackgroundprocessing—Celery,SQS,orKafka.
• CachingstrategieswithRedis,andknowingwhennottocache.
• Infrastructureascode(TerraformorAWSCDK).
• Observability—structuredlogging,metrics,tracing,andusefulalerts.
• NoSQLstores(MongoDB,DynamoDB)alongsiderelationaldatabases.
• Enoughfront-endfamiliarity(AngularorReact)todebuganintegrationendtoend.

CTC range is 10-12L