Ashim Saha
Verified Expert in Engineering
Full-stack Developer
Ashim is a software developer with nine years of experience. He specializes in using the Flutter toolkit to create mobile applications. He has delivered robust web apps, integrated and unit-tested web services with JavaScript, built tools to increase automation and reduce errors, and worked with cloud platforms and technologies such as AWS, Docker, and Kubernetes. Ashim creates tools that help companies automate and effectively improve their day-to-day performance.
Portfolio
Experience
Availability
Preferred Environment
Mobile App Development, Web Services, Flutter, Node.js, SQL, Full-stack, Back-end, Go, Rust
The most amazing...
...tool I've created was an end-to-end ERP application for mid-sized companies, enabling them to go paperless.
Work Experience
Full-stack Mobile Developer
Self-employed
- Created the mobile UI of the password manager mobile app from scratch using Flutter, FlutterFlow, and Rust.
- Tried to save the data locally in the device and securely. Due to this, I used Rust as the back end. The Flutter app talked to the Rust back end using FFI.
- Used Firebase to sign up and log in and for app monitoring purposes.
Senior Back-end Engineer
Atlan Pte Ltd
- Maintained the existing authentication and authorization services in Go. Also, built new APIs and implemented some of the SSO features.
- Migrated the Keycloak to the latest version and Keycloak SPIs.
- Used to debug several components of the back end to solve issues and maintain the existing codebase, and created new features.
Senior Mobile App Developer
Freelance
- Developed a Flutter-and-Dart-based application to manage accounting, invoices, expenses, etc.
- Designed a schema for an SQLite database so that user can store their data a mobile device.
- Developed print-and-share PDF features for invoices and other accounting documents.
- Created analytics UI and back-end services; with this users can perform analytics features like SUM, AVG, COUNT, MAX, MIN, and GROUP BY.
- Created a fully featured filter UI for analytics and list pages.
Senior Full-stack Developer
Freelance
- Worked closely with different clients to understand their requirements and pain points with their existing system and proposed a solution to the problem.
- Designed the architecture from scratch of a cloud-based business management application for a mid-size firm.
- Developed the REST APIs for the application using Go and Dgraph; chose GraphQL as the database query language to query Dgraph.
- Implemented a UI with the help of React, Redux, MUI, and some other open-source libraries of the whole business application.
- Implemented CSV exports, PDFs, statements, and report generation on the client side.
- Created a tool to increase automation and reduce errors for internal use.
- Designed and developed an end-to-end institute management app using React, Redux, and MUI for the front-end and FOXX microservice at the back end. That application was delivered to the client's on-premise server.
Full-stack Developer
SAP
- Implemented an authorization microservice that takes less than five milliseconds for 100 concurrent requests; to achieve this, also designed and implemented a custom distributed cache using Go.
- Designed and developed REST APIs to store and retrieve users, roles, and organizational hierarchy, where we have to follow HIPPA compliance. Also implemented authorization using the user roles and organization position.
- Implemented web-based UIs and integrated with REST APIs for the app's user management module to manage users, roles, and organization hierarchy using SAPUI5.
- Designed and developed back-end services for the patient cohort management system; this system assigned or removed large numbers of patients based on different parameters and sorted them into cohorts in a single API call.
- Tested the services using unit tests and integrated the test methodology.
- Participated in the journey of the monolith to a microservice architecture where we used cloud technologies like Docker, Kubernetes, and AWS to implement microservices.
Software Developer
Vanenburg Software Pvt Ltd
- Worked as part of the core team to build a cloud-based workflow engine—designing the data model to store the workflow and revising the workflow and its instances—and achieved high throughput and low latency for a large dataset by using NoSQL.
- Designed and developed secure REST API endpoints to create, edit, delete, view, and search for workflow and its instances in Java. Here role-based authorization was used to protect the APIs from unauthorized access.
- Implemented and unit-tested a custom expression executor with the help of an open-source library in Java. That executor had two inputs, an expression as a string and an object. The output of the executor was a single value.
- Implemented and united tested various utility functions and POJO classes (plain old Java object).
Experience
Business App for A Mid-sized Firm
Business Accounting, Invoicing, and Management App
I completed the end-to-end development from the front-end in Flutter to the back-end in dart and SQLite.
Institute Management App
I developed the back end with ArangoDB and used ArangoDB as a document database. The front end was built using React, MUI (Material UI), and Redux for state management.
User Management Module
We used HANA as a database, JavaScript for the back end, and SAPUI5 for the front end. I developed and maintained the user management module.
Back End for a Workflow Engine
My responsibility was to design the data model and schema for HBase. I also implemented the REST API and database interaction module, and I used JUnit to test different methods.
Education
Master's Degree in Computer Science
Cochin University of Science and Technology - Kochi, Kerala, India
Skills
Languages
JavaScript, Go, Dart, SQL, Rust, Java, HTML5, CSS, ECMAScript (ES6), GraphQL, TypeScript, HTML, C#, PHP, XML, cXML, Python
Frameworks
Flutter, Material UI, Redux, Express.js, JUnit, React Native, OAuth 2, Next.js, Apache Ranger
Libraries/APIs
React, Node.js, Redux-Saga, REST APIs
Paradigms
REST, Object-oriented Programming (OOP), Agile Software Development, Microservices Architecture, Unit Testing, HIPAA Compliance, Test-driven Development (TDD), DevOps, Microservices, Mobile Development, Agile, API/Services Architecture, ETL
Storage
Databases, Database Management Systems (DBMS), NoSQL, HBase, Cloud Deployment, SQLite, ArangoDB, Dgraph, PostgreSQL, MySQL, MongoDB, Azure Cloud Services, Relational Databases, JSON, Amazon S3 (AWS S3), Redis
Other
Web Services, Software Architecture, Full-stack, User Interface (UI), Back-end, API Design, Full-stack Development, Algorithms, Software Engineering, Mobile App Development, APIs, CI/CD Pipelines, API Integration, Containers, User Experience (UX), Ajax, Servers, SDKs, Mobile Apps, SOAP, SAP, OData, Finance, WebSockets, Performance, Security, Architecture, Front-end, Cloud Services, SaaS, No-code Development, ESLint, Single Sign-on (SSO), System Design, LDAP, Ranger, Team Leadership
Tools
Solr, SAP UI5, Firebase Authentication, Git, Apache Solr, Jenkins, Docker Compose, GitHub, GitLab, Keycloak
Platforms
SAP HANA, Linux, Android, Docker, Kubernetes, Firebase, Google Cloud Platform (GCP), Amazon Web Services (AWS), Mobile, Apple, FlutterFlow, Apache Kafka, Azure
Industry Expertise
Accounting
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