WideFix

WideFix is a software development agency led by Andrei Kaleshka, a Toptal-verified expert ranked in the top 3% of global freelance developers. Based in Poland, the firm specializes in fixing, scaling, and modernizing existing applications rather than starting from scratch. Kaleshka is the author of "Rails Task Management Essentials" and has been quoted by Yukihiro Matsumoto, creator of Ruby. The agency holds a 4.8/5 rating on Clutch and has been recognized by Techreviewer.co as a most trusted development partner. Their open-sourced libraries—Migration Data and Actual DB Schema—have been downloaded over 7 million times combined.

Services and capabilities

WideFix focuses on four main areas: application optimization and debugging, legacy system modernization, feature development and integration, and fintech expertise.

On the performance side, they identify and fix speed bottlenecks, memory leaks, and stability issues. They specialize in rescuing outdated Ruby on Rails applications plagued by bugs, crashes, or deprecated technology stacks. The firm claims to have increased organic Google traffic by 4000% through app optimization for at least one client and prevented account-sharing fraud that increased another client's revenue by 30%.

They build full-stack features end-to-end, design and develop new screens, and handle infrastructure optimization and architectural guidance. Their backend work centers on Ruby on Rails, Hanami, Sinatra, and custom Ruby solutions. On the frontend, they work with React, Next.js, Node.js, and TypeScript. Mobile development spans React Native, Swift (iOS), Kotlin (Android), and C++. Infrastructure includes PostgreSQL, Redis, AWS, Heroku, and Docker.

Fintech is a declared specialty. They integrate payment processors (Stripe, PayPal, Square) and accounting software (Xero, QuickBooks, Sage, Clearbooks, Kashflow), building financial workflows, reporting solutions, and data analysis systems. They also offer technical consulting for architecture design, technology selection, and performance audits, plus 24/7 monitoring and maintenance.

Notable work

WideFix built BudgetingKid, a financial education app available on web and mobile platforms, which they position as both a portfolio piece and a live product. The app received a 4.9★ rating on both app stores. Beyond that, their website references solving problems for unnamed clients—including a recent technical issue related to fake signups and a Ruby/Rails upgrade project—but does not name specific client companies.

How they work

WideFix offers a free app audit and consultation to start engagements. They conduct internal code reviews and QA before delivery. Contact is available at call@widefix.com or +48516295359. The source does not specify pricing models, contract lengths, or team composition for individual projects, though the founder emphasizes a "true partnership" approach and understanding client needs before building solutions.

Team and credentials

Andrei Kaleshka, the founder, is verified as a Toptal expert in the top 3% globally and is a published author. Team size is not disclosed. WideFix has a 4.8/5 rating on Clutch (suggesting multiple reviews) and was recognized by Techreviewer.co as a most trusted development partner. The firm serves clients across the US, Europe, the Americas, UK, and Australia. English proficiency is implied by their client base and published content, but not explicitly stated.