Top 10 API & Integration Modernization Companies (2026)

Compare API and integration modernization companies by the middleware and interfaces they cover, their modernization approach, and delivery experience. Check the linked migration guides, service guides, and vendor profiles before adding a company to your shortlist. Companies are listed alphabetically, without rankings or scores.

Approach labels below use the seven modernization options — which of the seven Rs fits an integration layer.

Updated 4 September 2026·Peter Korpak·Methodology

Compare api & integration modernization companies

Narrow the list by source stack, supplier type, team size, or region. Check each company's integration and consumer-migration experience against your requirements. We currently have no sponsors. Vendor inclusion, recommendations, and highlights are editorial decisions based on documented evidence.

The lists show recorded source and target technologies. They do not prove delivery of every combination. Follow the public evidence links to the checked claims below. “Public sources not reviewed here” means we have not checked those claims; it is not a judgment of the supplier’s performance.

Migrates from:

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API & Integration Modernization company comparison: recorded source and target coverage, approach, supplier type, team size, region, public evidence kind, and internal relationship records
Company	Recorded source → target coverage	Approach	Type	Team size	Region	Public evidence kind
AltexSoft	Recorded source → target coverageCoverage not recorded	Approach—	TypeDelivery firm	Team sizeMid-size	RegionUSA / Europe	Public evidence kindPublic sources not reviewed here	Internal relationship records0 internal relationship records
Cognizant	Recorded source → target coverageTo: MuleSoft Anypoint Platform	Approach—	TypeDelivery firm	Team sizeEnterprise	RegionGlobal (US HQ)	Public evidence kindPublic sources not reviewed here	Internal relationship records0 internal relationship records
Endava	Recorded source → target coverageCoverage not recorded	Approach—	TypeDelivery firm	Team sizeEnterprise	RegionGlobal	Public evidence kindPublic sources not reviewed here	Internal relationship records0 internal relationship records
Grid Dynamics	Recorded source → target coverageMonolith to Microservices, Kubernetes	Approach—	TypeDelivery firm	Team sizeMid-size	RegionUSA / Global	Public evidence kindPublic sources not reviewed here	Internal relationship records0 internal relationship records
IBM Consulting	Recorded source → target coverageTo: IBM z/OS Connect	Approach—	TypeDelivery firm	Team sizeEnterprise	RegionArmonk, NY, USA (global)	Public evidence kindPublic sources not reviewed here	Internal relationship records0 internal relationship records
Intellias	Recorded source → target coverageSOAP, Monolith to REST, GraphQL, Event-driven APIs	Approach—	TypeDelivery firm	Team sizeEnterprise	RegionUkraine (Global)	Public evidence kindPublic sources not reviewed here	Internal relationship records0 internal relationship records
N-iX	Recorded source → target coverageCoverage not recorded	Approach—	TypeDelivery firm	Team sizeMid-size	RegionEurope / Global	Public evidence kindPublic sources not reviewed here	Internal relationship records0 internal relationship records
PLANEKS	Recorded source → target coverageCoverage not recorded	Approach—	TypeDelivery firm	Team size—	Region—	Public evidence kindPublic sources not reviewed here	Internal relationship records0 internal relationship records
Techzert	Recorded source → target coverageIBM WebSphere MQ to Google Apigee, IBM API Connect, IBM App Connect, Tyk	Approach—	TypeDelivery firm	Team size—	Region—	Public evidence kindPublic sources not reviewed here	Internal relationship records0 internal relationship records
Thoughtworks	Recorded source → target coverageCoverage not recorded	Approach—	TypeDelivery firm	Team sizeEnterprise	RegionChicago, IL, USA (global)	Public evidence kindPublic sources not reviewed here	Internal relationship records0 internal relationship records

The count covers this site’s migration and service links for each company, listed under its entry. It does not count verified case studies or successful projects.

The checked public sources, scoped claims and limits for suppliers across hubs are published as an open vendor evidence dataset with CSV and JSON downloads.

Before requesting bids, use the API & Integration Modernization services guide to define the work, delivery responsibilities, project cost, and timeline.

What each company delivers in api & integration modernization

One entry per company, carrying only attributes we can point at a source for. Where a company has no published evidence for an attribute, nothing is shown rather than a placeholder.

AltexSoft
Agency
A travel-tech specialist whose engineering team publishes technical comparisons of REST, SOAP, and GraphQL architectures, with its deepest real-world integration experience built on complex third-party distribution APIs such as Amadeus for travel and hospitality clients.
Firm profile
Mid-size · USA / Europe
Cognizant
Agency
A global strategic systems integration partner of MuleSoft, running API-led integration strategy, architecture, build, and legacy-platform migration onto the Anypoint Platform and CloudHub iPaaS.
Modernizes to
MuleSoft Anypoint Platform
Firm profile
Enterprise · Global (US HQ)
Endava
Agency
Legacy core-system assessment and re-architecture through its own patented Dava.X toolset, paired with published technical guidance on API management platforms — gateways, developer portals, lifecycle governance — using Apigee as a worked example.
Firm profile
Enterprise · Global
Grid Dynamics
Agency
Monolith decomposition into microservices on containers and Kubernetes — strangling legacy applications rather than rewriting them — as the core of its Application Modernization practice, citing 10x speed-to-market gains across Fortune 1000 implementations.
Modernizes
Monolith to Microservices, Kubernetes
Firm profile
Mid-size · USA / Global
IBM Consulting
Agency
IBM Consulting's documented integration work here is the BCC Iccrea z/OS Connect project, which let IBM Z banking applications call external REST APIs. IBM's own integration software, formerly Cloud Pak for Integration, is the product line for API management and event streaming.
Modernizes to
IBM z/OS Connect
Firm profile
Enterprise · Armonk, NY, USA (global)
Intellias
Agency
A dedicated API Modernization Services practice that replaces outdated SOAP-based interfaces and monolithic integrations with governed REST, GraphQL, and event-driven APIs, secured with OAuth 2.0 and JWT.
Modernizes
SOAP, Monolith to REST, GraphQL, Event-driven APIs
Firm profile
Enterprise · Ukraine (Global)
N-iX
Agency
A System Integration Services practice that designs enterprise service buses and API-based integration layers connecting legacy and cloud-native systems, reporting data accuracy up to 98% across delivered integration projects.
Firm profile
Mid-size · Europe / Global
PLANEKS
Agency
Incremental API modernization rather than full rewrites — layering FastAPI and Celery/Redis around a stable Django core and isolating third-party integrations behind dedicated retry and caching layers — under its own API Modernization Services practice.
Techzert
Agency
An IBM ecosystem specialist running API management and integration-middleware migrations across Google Apigee, IBM API Connect, IBM App Connect, and Tyk, alongside legacy WebSphere MQ and Cloud Pak for Integration delivery.
Modernizes
IBM WebSphere MQ to Google Apigee, IBM API Connect, IBM App Connect, Tyk
Thoughtworks
Agency
Thoughtworks documents AI-assisted modernization of a client's 25-plus backend APIs on .NET Framework 4 using its AI/works platform, and a client story on decommissioning legacy PHP 7 services at Docebo.
Firm profile
Enterprise · Chicago, IL, USA (global)

Market map

Companies to evaluate for API & Integration Modernization

Scope: published api & integration modernization companies with documented category, migration-path, or service evidence in this research domain.

Last evaluated 4 September 2026

208

Published modernization companies reviewed

Companies shown for api & integration modernization

Consultancies & integrators 10

Inclusion criteria: A company must have a published profile and documented category, migration-path, or service evidence in this domain. See the evidence threshold in our research methodology.

How to choose: Start with documented buyer fit (0 profiles) and specialty evidence (10), then narrow by team size (8) and location (8). Open a profile to verify the underlying experience before shortlisting.

This is an alphabetical market map, not an ordinal ranking. Inclusion is based on documented evidence and editorial review.

API and integration modernization suppliers divide into platforms and delivery partners. Platforms provide API management, gateways, iPaaS, event streaming, service connectivity, and integration observability; consultancies and integrators inventory dependencies, design the target architecture, migrate interfaces, and establish governance. Compare platforms by protocol coverage, connectors, policy controls, deployment model, portability, and lifecycle cost. Compare partners by legacy middleware expertise, integration-scale evidence, security capability, delivery capacity, and location. The roster is alphabetical and should be filtered by architecture and program fit.