What does an Internet Information Services (IIS) developer do?
An Internet Information Services (IIS) developer builds and configures Windows-hosted web applications by managing site structures, application pools, and configuration files. This role focuses on the server-side environment that allows web workloads to run reliably on Microsoft IIS. The developer maps physical paths to virtual directories and sets worker process parameters to control how applications execute. They also implement HTTP routing rules and secure runtime permissions for specific application identities.
- Designs the IIS architecture by creating sites, applications, and virtual directories that map to the correct physical paths on the server. This structure determines how incoming requests reach the intended codebase and ensures the hosting model matches the application requirements.
- Configures application pools and worker process settings to manage memory usage, recycling behavior, and identity permissions. These settings directly affect how apps run under IIS and isolate different workloads to prevent conflicts or security breaches during execution.
- Authors XML-based configuration in web.config and applicationHost.config to control per-application behavior and global defaults. The developer uses these files to override settings for specific environments and manages changes through tools like appcmd.exe for consistent deployment across servers.
- Implements HTTP routing and rewrite behavior using modules such as URL Rewrite and Application Request Routing (ARR). This work directs inbound traffic to the correct backend services and handles proxying rules when the application requires complex request handling or load balancing.
- Troubleshoots app execution issues by verifying application pool settings and analyzing process model behavior during runtime. The developer identifies configuration errors that cause failures and applies fixes to restore stable operation for the hosted web workload.
How to hire an Internet Information Services (IIS) developer on Upwork
Step 1: Post a job
Define your Windows hosting needs clearly to attract qualified candidates. Use the Job Post Generator powered by Uma™, Upwork's Mindful AI to draft a precise description in seconds. Describe your requirements in a few sentences and Uma creates a tailored post for this role. You can write a new post, update a saved draft, or reuse an existing one.
- Specify whether you need configuration of application pools, worker process settings, or virtual directories for your web workloads.
- List required tools such as IIS Manager, appcmd.exe, or the URL Rewrite Module to filter for technical fit.
- Clarify if the role involves managing web.config overrides or global applicationHost.config defaults for your environment.
Step 2: Evaluate candidates
Look for proof of hands-on experience with IIS architecture and deployment workflows. Uma can run instant video interviews and build shortlists with side-by-side comparisons to speed up your review. Focus on candidates who demonstrate clear understanding of request routing and security models.
- Check for portfolio examples showing deployed IIS configurations for sites and applications with specific pool settings.
- Verify experience implementing HTTP routing rules using URL Rewrite or Application Request Routing for inbound traffic.
- Review documentation samples that describe configuration steps and troubleshooting outcomes for runtime behavior issues.
Step 3: Interview your top choices
Discuss specific technical scenarios to gauge practical knowledge of the IIS config system. Schedule and conduct interviews within Upwork Messages to receive an immediate transcript and summary after each session. Ask about their approach to automation and error resolution.
- Ask how they configure application pool identities to manage security permissions for specific web applications.
- Request examples of how they use appcmd.exe or configuration delegation to automate IIS changes across servers.
- Discuss their method for troubleshooting worker process crashes or performance bottlenecks in production environments.
Step 4: Agree on scope and begin work
Set clear deliverables and milestones for your IIS configuration project. Use Upwork Messages and the contract workroom for all communication and project management tasks. Identity verification, payment protection, hourly tracking, and project funds add security to your engagement.
- Define milestones for delivering web.config files, URL rewrite rules, and verified application pool settings.
- Agree on a timeline for deploying configuration changes and documenting the steps for future maintenance.
- Establish criteria for accepting troubleshooting outcomes, such as resolved runtime errors or optimized request handling.
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