#1
ELEKS
Strong engineering vendor for complex business software.
- Best fit
- custom software, data systems, and enterprise platforms
- Price range
- USD 50 to USD 99 per hour
- Team size
- 2000 plus
VendorProof category guide
Verified Api Integration Companies
API integration buyers need clear proof before they talk to vendors. The goal is to see relevant work, understand the team, and compare price and delivery fit without reading vague sales copy.
VendorProof compares companies by public reputation, project evidence, team size, case studies, pricing context, and fit for the category.
Verified API integration companies
Rankings are based on proof signals such as relevant work, pricing context, team size, buyer fit, and public reputation.
#2
Itransition
Useful choice for long running business software programs.
- Best fit
- software modernization, portals, and enterprise systems
- Price range
- USD 25 to USD 49 per hour
- Team size
- 3000 plus
#3
ScienceSoft
Established vendor with broad service coverage and mature process.
- Best fit
- software development, QA, and IT consulting
- Price range
- USD 50 to USD 99 per hour
- Team size
- 750 plus
#4
BairesDev
Large talent network for ongoing software delivery.
- Best fit
- dedicated software teams and product engineering
- Price range
- USD 50 to USD 99 per hour
- Team size
- 4000 plus
#5
STX Next
Good fit for Python led backends and product engineering.
- Best fit
- Python, web platforms, and dedicated teams
- Price range
- USD 50 to USD 99 per hour
- Team size
- 500 plus
Related Software Development categories
Narrow the search by platform, project type, or delivery need.
Custom Software DevelopmentVerified custom software development companies
Enterprise Software DevelopmentVerified enterprise software development companies
SaaS Product DevelopmentVerified SaaS product development companies
Api IntegrationVerified API integration companies
Legacy ModernizationVerified legacy modernization companies
Qa AutomationVerified QA automation companies
Product MaintenanceVerified product maintenance companies
How to choose a API integration partner
Use these checks before sending a brief or booking a sales call.
Ask for matching workLook for projects close to your platform, audience, budget, and timeline.
Check team ownershipConfirm who handles planning, design, engineering, QA, and post launch work.
Review pricing earlyCompare hourly ranges, project minimums, and what is included in the estimate.
Look for proofCase studies, public reviews, shipped links, and clear process notes are better than claims.