Solutions Architect - 21902 Outstaffing

Project Delphi Developer, Linux Administrator, Embedded developer,

Roles Linux Kernel Developer

Customer Netis Systems and others

Project It was an old Norwegian company, which primarily focused on

automotive robotics and system integration, had some struggles with networking and support and was looking for interns to get things done.

Participation I got on board after implementing an RTMP server from scratch using plain Delphi components as an Intern, after two years got a title of Linux System Admin, but primarily focused on mbed systems and drivers development.

Had been engaged mostly as a remote part-time employee, due to age restriction and strict mentorship.

Project Mbed Developer, Linux Kernel Developer

Roles Customer Ericsson, few GSM providers and Military related projects

Project There were two projects:

• QoS metrics for GSM networks

• in-house developed RTOS development for Military purposes

Participation Helped with QoS packet processing and metrics implementation.

We've decided to put packet processing outside the linux kernel, 'cause I had some previous xp on the subject, and implement a poll-mode network driver for a custom NIC afterwards.

It was a pretty unconventional approach, which translated over the years into the most performant networking/storage solutions - Intel's DPDK and SPDK frameworks.

The other project was about designing a custom CPU with erlang BeamVM bytecode execution capabilities, similar to how Sun Sparc handled JVM bytecode.

Team 3 developers, including me

1 Senior MBed Systems architect

1 Senior C/C++ developer

Database An in-house developed one and PostgreSQL

Tools

• Eclipse

• IAR

• Xilinx ISE

• ModelSim

Technologies

• Linux Kernel Networking

• packet_mmap based packet processing

• pool mode user space network drivers

• Erlang and BeamVM

• Golang (nothing serious)

• Basic machine learning

• Java SE and a bit of EE

Project Fullstack Developer, Mobile Developer, SysAdmin

Roles Customer A whole bunch of customers

Project Had plenty of

• CRM's / ERP's on ZKoss / Vaadin with legacy extjs UI

• Different Marketplaces

• Salesforce and Alfresco based solutions

• iOS and Android applications

• Angular1 Webapps

• Puppet/Chef provisioning and administration

Participation Got tired of mbed projects, and went for part-time freelancing as a fullstack developer.

Mostly support and refactoring of the existing projects.

Team Up to 5 members

Database Mostly PostgreSQL, sometimes MySQL.

Rarely MongoDB, but was moving to Postgres anyway.

Had been working with a Hadoop based data mining project, it was based on Hive and Cassandra.

Tools Way too many...

Technologies

• Flash AIR / Haxe / robotlegs

• Cappuccino Framework Objective-J (a memorable one)

• ExtJS

• Vaadin

• Zkoss

• Groovy on Grails

• Node.js

• Angular1

• Asterisk telephony

• Android SDK for Android 3

• Cocoa SDK and basic ObjC

• J2ME

• Rest API's design

• Hadoop stack

• Cassandra

• MongoDB

• Spring framework

• Clojure (nothing serious)

• Scala with Play framework and Lift framework

• Golang (for rest API's)

Project Streaming Solutions Architect, Senior Developer

Roles

Customer Mostly Akamai and few RTB related companies

Project Real time RTMP streaming projects, mostly based on

Scala/Akka with a custom ad-hoc dynamic network routing with an unstable topology and congestion.

Participation Developed real time RTMP streaming services and OpenRTB projects with custom Data Providers.

Implemented a Data Mining Provider SDK for iOS and Android. Implemented a custom RTB stack on top of Seastar framework and DPDK.

Developed a few React frontend apps and few react-native mobiles apps with use of the aforementioned RTB SDK.

Had to leave the company due to the conflict of interest.

Team 6-10 team members, depended on the project

Mostly Senior staff members.

Database Cassandra

Tools Way too many to enum...

Technologies

• Scala / Akka

• RTMP streaming

• OpenRTB / rtbkit

• DPDK

• Hashicorp stack (terraform, consul, nomad, vault, packer)

• RxJava / RxJS

• Swift

• ReactJS

Project Senior Developer, Senior Advisor, Solution Architect

Roles Customer Can't disclose

Project Mostly involved part time engagements in internal and

OpenSource projects

Participation Part time engagements had few law enforcement related projects and learned a lot about ML and data science, can't disclose much.

Had been working on Power8 and Power9 afterwards CPU related optimizations.

Curated a few IBM's OpenSource projects.

Team Teams of 10-16 members

Database

• HP Vertica

• PostgreSQL

• Cassandra

• MongoDB

• CouchDB

Tools

Technologies

• Kotlin

• Scala

• Swift

• React Native

• Tensorflow

Project Senior Mobile Developer, Senior FullStack Developer, DevOps,

Roles Team Lead

Customer Internal Project

Project Had been developing a React Native application for document

workflow management targeting board of directors.

Participation Implemented a custom PDF1.4-2.0 rendering engine.

Had to leave because the project was disbanded due to lack of workforce and poor management.

Team me and other 2 guys - a middle and a senior developer, team

grew to 15 people over a course of year

Database PostgreSQL

Tools IntelliJ IDE's, VSCode etc

Project Roles Team lead, Mobile Developer, DevOps

Customer Khosla ventures related EDTech startup for ChildMinders and

Private schools. Can't disclose the exact company.

Project A SaaS solution for Childminders and Private schools, with

whitelabeling and real time media streaming support.

Participation Ported and refactored a legacy 10 years old ObjC app to Swift, and existing legacy 3 years old android app from Java to Kotlin.

Implemented GRPC API's on PHP (yeah...)

Deployed a custom self-hosted testfarm on OpenSTF.

Team 2 android and 2 ios developers, including me

1 delivery manager

1 project manager

Database PostgreSQL

Tools

• XCode

• AppCode

• VSCode and others

Technologies

• Swift

• RxSwift

• RxFIow

• RxDataSources

• SwiftUI

• Carbon

• DifferenceKit

• Kotlin

• Koin

• Android

• Android Jetpack

• Android NDK

• RxJava2

• Fastlane CI/CD with Ruby scripting

• Bazel builds

• Custom testfarm on top of OpenSTF

• GRPC API's

Customer Business Information and Media

Project Internal graph database

Participation Had been refactoring existing API's from Play2 to finagle/finch using shapeless based endpoint handlers to make 'em framework agnostic.

Documented existing HTTP API with Swagger.

Implemented API integration tests with Gatling.

Ported to KNative with a custom DevOps stack on top of Kubernetes and Operator Framework with deep OpenServiceBroker API integration.

Performed tech design of pluggable data stores and indexing (both SPDK based).

Team 1 delivery manager

1 project manager / part time senior developer

2 part time senior developers

1 part time tester

Database Cassandra 3

Tools scala / sbt, golang, swagger, gatling, Knative, terraform, consul,

envoy, linkerd2

Technologies

• akka

• play framework

• javascript

• react

• ember

• Kubernetes

Project Senior Scala Developer, DevOps, Solution Architect

Roles Customer Business Information and Media

Project Internal custom xp and engagement project

Participation Had been automating cassandra infrastructure management, implemented a custom cassandra backup tool and a custom automation tool for concurrent service management and orchestration, similar to Kubernetes Operators but able to handle concurrent actions and respective resource synchronization.

Team 1 delivery manager

1 project manager

5 middle developers

Database Cassandra 3

Tools Datadog, InfluxDB, Graphite, Terraform, Terratest, Terragrunt

Technologies

• Java Spring

• Java Vert.x

• Scala Akka and Flink

• Kubernetes operators

• React, mobx-state-tree

• rx.js

• AtlasKit

Project Team Lead, Senior Scala Developer, DevOps, Solution Architect,

Roles Senior Native Mobile Developer

Customer NDA

Project Internal R&D regarding hybrid compilers and formal languages,

and a startup regarding automated mobile and web app testing for further funding and estimates

Participation Leading R&D regarding formal compilation approaches.

The idea is to be able to make all the architectural decisions at compile time, for instance how to “split an app” into frontend and backend, how to implement API’s, how to manage API versioning and migrations, how to split an app into microservices etc.

Team me

2 interns

3 senior developers

3 solution architects

Database In-house Database

Tools In-house stack on top of AWS and GCP

Project Tech Lead, AWS&GCP Solution Architect, Senior Scala

Roles Developer, Senior Golang Developer, Senior React Frontend

Developer, DevOps

Customer Google-related Companies

Project KYC/KYB solutions and related data-mining

Highload banking app with more than 1M active users

Participation Participated in pre-sales, solution discovery, solution architecture development, staffing, various requirement development sessions.

Implemented highload capable User session management services using managed denormalization across multiple databases. Ported the existing apps from MySQL/MongoDB to PostgreSQL + ScyllaDB stack. Improved the existing QA using modern approaches like Mutational Testing and Fuzzing. Implemented Acceptance Testing scenarios and SRE metrics for the whole product.

Team Complex teams, around 20-50 people each.

Database ScyllaDB, PostgreSQL, MySQL, MongoDB, Firebase/Firestore

Project Solution Architect, Senior Scala Developer, Senior Golang

Roles Developer, Senior React Frontend Developer, DevOps

Customers ADTech Company, Multiple IOT related companies, Large

Enterprise

Projects Legacy OpenRTB solution

Highload IoT ETL projects in golang and Legacy Akka Classic

Participation Implemented OpenRTB Ad exchange according to the latest standards and conventions. Introduced new Business Opportunities by inventing a new type of Ad Exchange

Refactored IoT ETL storage completely - ported to ScyllaDB and PostgreSQL with storage segregation (hot/warm/cold storage on SSD’s/HDD’s/Tape) and managed denormalization (only the data of the active users gets indexed and denormalized for higher availability), which reduced storage costs 5x times.

Moved from AWS RDS to a custom PostgreSQL distro due to scalability and lack of proper support on AWS side.

Team Small team, around 40 people