Frontend Modernization

Next.js Codemods are the automated code-transformation scripts Vercel ships with the framework, run through the @next/codemod CLI, to rewrite a project's code when a Next.js release deprecates or renames an API. Vercel published the @next/codemod package in October 2020 alongside Next.js 10 and has added a new set of transforms with most major releases since, including Next.js 13, 14, 15, and 16. Each codemod targets one specific breaking change, such as converting next/image imports or updating middleware geo/ip usage, so a major upgrade typically requires running several in sequence, and coverage is limited to the changes Vercel has chosen to automate.

jscodeshift is an open-source command-line toolkit for running codemods, scripted AST-based find-and-replace transforms, across many JavaScript or TypeScript files at once instead of editing each file by hand. Meta (then Facebook) published the first version to npm in March 2015 and continues to maintain it on GitHub under the facebook org; it is free to use and requires no license or account. It supplies the parser, AST query API, and test runner that most published React and Next.js upgrade codemods are themselves built on top of — it is a building block for writing transforms, not a ready-made migration for any specific framework.

Toptal is a network of freelance software developers, designers, and finance experts, which it describes as the top 3% of applicants. It provides on-demand senior talent for frontend modernization projects.

Thoughtworks is a global technology consultancy headquartered in Chicago. It was taken private by Apax Funds in a transaction announced complete on November 13, 2024. Martin Fowler, who works at Thoughtworks, named and described the Strangler Fig pattern after watching colleagues modernize legacy systems gradually. Its published client work centres on re-architecture and incremental modernization.

TestPros provides independent IT assessment and testing services, specializing in test automation for large-scale modernization projects in regulated industries.

SoftServe combines engineering services with industry verticals, particularly healthcare and retail. Its Adaptive Modernization Platform (SAMP) is a platform-as-a-service accelerator for building self-service platforms on AWS and Azure, aimed at platform engineering and cloud modernization rather than any single source technology.

Slalom takes a "strategy-first" approach, aligning the business case for modernization with the technical execution. It has partnerships with AWS, Azure, and Google Cloud.

PITSS is a specialist in Oracle Forms modernization. Their proprietary tools automate the analysis and migration of Oracle Forms and Reports to technologies such as Java, React, and APEX, which PITSS positions as lower in risk and cost than manual rewrites.

Mobilize.Net no longer operates as an independent vendor. In January 2023 it agreed to sell its data business to Snowflake and its application migration business to Growth Acceleration Partners (GAP), and the Snowflake acquisition closed on February 10, 2023. Snowflake took the SnowConvert data migration tools and the BlackDiamond Studio developer tools. GAP took the WebMAP family of cloud-native application migration products, the Visual Basic Upgrade Companion (VBUC), the services teams, and the Mobilize.Net brand and website. The mobilize.net domain now redirects to GAPVelocity.ai.

Grid Dynamics specializes in enterprise digital transformation, with a focus on retail and CPG. It modernizes monolithic commerce platforms into microservices-based cloud architectures.

Globant uses AI ("Augmented Coding") to accelerate the understanding and refactoring of legacy code. Its work is oriented toward modernizations driven by customer experience (CX) goals.

EPAM is a software engineering services firm. Its modernization work goes beyond migrating code to re-engineering it into modern digital products, and its published modernization tooling includes the AI/RUN platform (AI-assisted migration and modernization on AWS) and KubeRocketCI, an open-source application delivery platform.

Cognizant is ranked #1 in Application Modernization by HFS. Its "Skygrade" platform uses generative AI and modern tooling to accelerate cloud-native transformations, particularly in banking and healthcare.

Codurance is a software consultancy focused on software craftsmanship, TDD, and clean architecture. They specialize in modernizing legacy systems with a focus on quality and maintainability.

Braintrust is a user-owned talent network that connects enterprises with technical talent. It focuses on modern tech stacks including React, Next.js, and Web3.

Brainhub, founded in 2015 in Gliwice, Poland, is a 500-person software engineering agency part of the STX Next group. Specializes in AI/ML and software modernization. Recognized by Deloitte Technology Fast 50; 4.9/5 Clutch rating from 42 reviews. Typical rates: $50-99/hr.

Accenture is a global professional services firm with a mainframe modernization practice. It combines strategic consulting with large-scale delivery and partnerships with the major cloud providers. Its "myNav" platform is used to chart migration paths.

10Clouds is a software house with a Warsaw address (Chmielna 73). Its homepage counts 17 years in business and currently positions the company around AI for banks, insurers and fintechs. It also lists React engineering and an AWS migration service.