SWE & Architecture
I make mobile apps work really well, really quickly.
Hi! I'm
Nikita “Nek.12” Vaizin
I'll audit your codebase, fix the biggest bottlenecks, and train your devs to ship up to 2x faster.
I'm an AI + Mobile Dev consultant. Get faster delivery, fewer production issues, better product metrics. Hop on a free 20-min call to get 3 highest-leverage fixes + a plan
My Skills
I coded for 6000 hours, built 10+ apps with 1M+ users, and trained 300 devs - now I give my knowledge to businesses.
AI & DevEx
I make devs faster & happier with applied AI and developer tooling.
Psychology & UX
I turn users into fans through behavioral science and product design.
Leadership & Education
I turn juniors into seniors and boost team velocity
How I help teams ship better apps
I can audit code, analyze team dynamics, teach your devs a new stack, or solve a specific technical problem
Codebase health audit
I'll analyze your codebase and find how to improve performance, stability, and dev speed
Team velocity audit
Wonder why your devs are so slow? Not delivering? I'll be the unbiased third party that gives solutions
Stability & Performance audit
App is crashing? Bad reviews out of nowhere? Freezes? I will find the causes and how to fix them
System design
Building a complex app or system? I will design it end-to-end, so that your devs can execute unhindered
Team enablement
Onboarding, mentoring, interviewing, productivity audits, and training programs.
AI integration
Your devs can be 3x faster with AI. I will teach them how to and set everything up
Proven industry-leading expertise
My work is public & I got stats, testimonials, & reviews from my students, clients, and users
6,500+
hours spent coding
That's ~16 yrs of experience.
10+ apps
built for companies
Worked on apps with 1M DAU & $20M funding.
2 million
lines of code optimized
I made even the biggest apps better.
200-person
teams worked with
Led teams of 5+ engineers inside large orgs.
30+ interns
trained 0 -> middle
I trained interns, then they found jobs.
250+
students graduated
I taught CS at my country's most prestigious university
I make numbers go up
Before/after results from production apps.
App startup time
-15.3s17s → 1.7s
Optimized app startup - reduced churn by 43%.
Game loading time
-37.6s40s → 2.4s
Redesigned a game engine to cut loading times - doubled engagement.
Crash-free rate
+7.95%92% → 99.95%
Boosted an app from 1⭐ reviews to crash-free
ANR-free rate
+1.7%98.2% → 99.9%
Devs couldn't figure out where freezes are coming from. I did.
My projects
I built widely used products & apps and got hands-on experience shipping
FlowMVI
Kotlin Architecture Framework with 800 GitHub ⭐s.
- • 3rd most popular Kotlin architecture framework
- • Used in prod in commercial apps to deliver the results above
- • Loved by hundreds of devs for doubling their speed
Respawn
AI-powered self-improvement app built end-to-end by me.
- • 150k+ lines of code
- • 50k+ users
- • Revenue in production
Education & teaching
- Designed and taught a mobile development course for 200+ students.
- Built a training program and took 32 trainees from 0 to middle roles.
- BSc in Computer Science & Economics (GPA 9.5 honors diploma).
- Published scientific research papers.
Writing & community
- ~6,000 average views per article
- YouTube videos up to 4,000 views
- 500+ blog subscribers
- Speaker & Expert at Conferences
Click to expand
Recent posts
All my content is free forever & based on hands-on experience
I write because teaching and building are my passions.
Development
Case Study: How I Sped Up Android App Start by 10x
Real case study of Android app optimization: how to reduce cold start time from 17 to 1.7 seconds, improving retention from 82% to 98.5%. Concrete solutions: migration to Splash Screen API, background task system, reactive data loading, and backend optimization.
AIPersonal
I've been using OpenClaw for a month now. Full review: what it is, why the hype, and whether you should try it
OpenClaw (formerly ClawdBot) by Peter Steinberger is a personal AI assistant with file-system access, background agents, and remote control. This post covers its origins, hype, and my hands-on take.
Development
AGP 9.0 is Out, and It's a Disaster. Here's Full Migration Guide so you don't have to suffer
I migrated 150k lines of code to AGP 9.0 and wrote a comprehensive, step-by step guide to migrating large Kotlin Multiplatform projects from AGP 8 to AGP 9, covering all breaking changes including removed build types, BuildConfig issues, NDK restrictions, and the new DSL syntax.
PersonalDevelopment
My New Product is Myself. How I Became a Consultant in the Age of AI
I found my calling as a consultant - the story of how I saved a business millions and created my best product - myself.
AIDevelopment
What are AI agent skills and how to use them - complete breakdown with examples
Agent skills are a way to progressively disclose context to AI through markdown files, which saves tokens and boosts performance. I explain why you need them, when to use them, how to create them, and debunk the myths.
AIPersonal
I No Longer Write or Read Code. AI Does It Better Than Me
In December, AI models crossed a threshold after which I became useless as a programmer. Now I push code to prod that Ive never read.
DevelopmentAI
Agents and Gradle Don't Get Along - I Fixed It in Two Commands
Introducing ksrc - a CLI utility that simplifies searching and viewing Kotlin library source code from 15+ commands down to two for your AI agents.
Personal
Going independent for six months starting in 2026
Starting in 2026, Im going independent for at least six months - will be building my own product full-time and building in public.
Personal
Pulse in ChatGPT - how did I even live without this?
Im sharing how the Pulse feature in ChatGPT Pro proactively puts together a daily personalized digest for me - from Crashlytics crash fixes to Kotlin, Compose, and Jetpack updates. I explain why this is one of the most useful AI use cases for me.
AIDevelopment
I spent 400 hours working with AI agents and found the best one - here it is.
Detailed comparison of Codex and Claude Code after three months of using both tools. Breaking down the pros and cons of each, model features, harnesses, pricing, and revealing who I paid $200/month to
Development
I compared 17 Kotlin MVI libraries across 103 criteria - here are THE BEST 4
Comparison of MVIKotlin, FlowMVI, Orbit MVI, and Ballast based on research across 70 Kotlin architecture libraries and 100+ criteria, with examples, pros, cons, and use cases for each. Includes a public spreadsheet comparing 70 Kotlin MVI and state management libraries.
Development
I Found the #1 Cause of Freezes in Your app, and Here's the Proof
SharedPreferences in Android are leading to ANRs through a hidden mechanism that Google tried to lie to you about. I completely expose them with proofs.
Development
I achieved 0% ANR in my Android app. Spilling beans on how I did it - part 1
After a year of work, I reached 0% freezes (App Not Responding or ANRs) in my app. Sharing a complete guide with 12 tips: from removing SharedPreferences and enabling StrictMode to fighting memory leaks.
Development
How I built a game engine using MVI in Kotlin and avoided getting fired
I rebuilt a legacy game engine from scratch using MVI architecture and Kotlin, 7000+ -> 400 lines, 20s load time -> to 1.75s, crashes from 8% to 0.01%, and 1700% better event processing throughput.
Development
How to make Android notifications 100% reliable
A comprehensive guide to making Android notifications and alarms completely reliable, based on years of real-world experience building an alarm clock app with zero notification failure reports.
Personal
Why I switched to a split keyboard - and you should too
In August, I switched to the Piantor Pro split keyboard with 40 keys and the Colemak DH layout. It turns out that traditional QWERTY keyboards are relics of the past, while split keyboards are much more ergonomic, portable, and efficient.
Development
I Built a Wear OS App in One Evening. Full Guide and All the Google API Pitfalls
Built a Wear OS companion app in one evening, ran into terrible Java-based Google APIs and half-documented Horologist. Sharing my experience and step-by-step guide on how to avoid the main pitfalls when developing for watches.
Development
I Won't Make You a Reproducer
I wont make you a reproducer. Stop asking.
PsychologyPersonal
How to deal with toxic families - a practical guide to boundaries and accountability
A comprehensive guide on dealing with toxic family dynamics through structured conversations, exploring your emotions, and enforcing boundaries - including specific frameworks for creating accountability and knowing when its time to walk away.
PsychologyPersonal
How to work through emotions via journaling: my template after 4 years of Gestalt therapy
An 8-question template for an emotions journal, based on 4 years of experience in Gestalt therapy. Helps fully work through and resolve uncomfortable emotions through sequential entries.
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