Technical SEO Agency: Audits, Fixes and Site Architecture That Let Content Rank

Updated September 2026 · Written and maintained by the Progression Agency strategy team

A technical SEO agency finds and fixes the things that stop a site from being crawled, indexed, rendered and ranked: crawl waste, index bloat, rendering problems, slow pages, broken structure, duplicate content, hreflang, schema and migrations. Buyers comparing a technical SEO company with a roster of technical SEO experts are really asking one question: who can read server logs, rendered output and page templates, and then get the fixes shipped? Technical SEO work sits with Progression Agency, which operates from New York for companies across the United States and worldwide. This page explains what technical SEO covers, what a technical SEO audit service delivers, how fixes get implemented in real codebases and platforms, what changes for ecommerce, enterprise and JavaScript sites, how migrations are protected, what a technical SEO consultant should report, and what it costs.

What technical SEO covers

The technical SEO audit service

An audit crawls the site, reads log files and Search Console, tests rendering and speed, checks structure, schema and international setup, and produces a prioritized list of issues with the fix for each, the effort, and the expected effect. It is a deliverable you can hand to developers or have us implement. Our SEO audit service page covers the full audit; this page is the technical half.

Getting fixes shipped

Findings are written as tickets with acceptance criteria; fixes are implemented in WordPress, Shopify, Webflow or a custom codebase where access allows, or handed to your team; each fix is verified after deployment by re-crawl and Search Console. Our WordPress development page and custom development page cover the platforms we work in. A technical SEO services agency that hands over the audit and leaves the tickets with you has done half the job, which is why checking each fix after deployment belongs in the work.

Edge SEO when the platform will not cooperate

Some platforms and release queues make even small changes slow. Working at the CDN lets us rewrite a title, add a canonical or hreflang tag, or issue a redirect as the page passes through, with no deployment on the origin. It suits stopgaps and tests. It also adds a layer developers must know about, so every rule gets documented and kept under version control, with a plan to move the fix into the codebase.

JavaScript frameworks and rendering

React, Next.js, Vue and Angular sites need rendering strategy (server-side rendering, static generation, hydration checks), crawlable links, and testing with how search engines actually render. Our Next.js development page covers the framework side. Angular SEO work often comes down to choosing a render mode per route, prerendered or server-rendered for anything meant to rank. A JavaScript SEO audit then compares raw HTML with the rendered page by template, so missing links, titles and copy show up in batches.

JavaScript SEO: what we test first

We start from how Google handles these sites: pages are crawled, queued for rendering and then indexed, and you cannot easily tell from the outside which stage a page is waiting on. So we test what each stage sees. We read the raw response, the rendered DOM in the URL Inspection tool, and the scripts and API calls the page depends on, looking for anything blocked in robots.txt.

Content that loads only after a click or a scroll gets its own check. So do internal links built as click handlers instead of anchors, which Google generally cannot follow. We also assume an AI crawler may read only the raw HTML, so key copy and links should be there before any script runs.

Single page application SEO: routes, status codes and titles

One HTML shell serves every view and the browser swaps content in afterward, which creates failure modes a normal site does not have. Routes built on fragments are the first thing to check: Google says it cannot reliably resolve them and asks for the History API, with real anchor links carrying an href. Error views are next. A client-side router can show a not-found message while the server answers 200, and Google’s documentation warns about that soft 404 pattern, so we redirect those to a true 404 URL or add noindex.

Titles, descriptions and canonicals also have to change on each route, and that is where React SEO problems usually hide, since a default React setup ships the same head on every view until someone adds per-route metadata or server rendering.

Ecommerce technical SEO

Faceted navigation rules, canonicalization of variants, pagination, out-of-stock handling, product schema, feed alignment and speed on large catalogs. Our ecommerce SEO page covers the wider program.

Enterprise technical SEO

Large sites need crawl budget management, log analysis at scale, templated fixes, governance for changes by many teams, and monitoring that catches regressions. Our enterprise SEO page covers the model.

Speed and Core Web Vitals

Field data by page type, fixes in order of impact and proof in conversion rate. Our website speed optimization page covers the project.

Large sites need crawl budget management, log analysis at scale, templated fixes, governance for changes by many teams, and monitoring that catches regressions.

International and hreflang

URL structure by market, hreflang with return links and x-default, canonical alignment and testing. Our international SEO page and the free hreflang checker cover it.

Migrations and redesigns

URL mapping and redirects, content parity checks, staging crawls, launch-day monitoring and post-launch verification. Our website migration page covers the process. For a new build, SEO website design puts these checks in the scope before design begins. Google SEO on a subdomain, such as a blog or store moved off the main site, depends on that subdomain having its own robots.txt file, because the main site’s file is not valid for other subdomains.

Technical SEO for AI search

AI crawlers need access, extractable content and clear structure; the same technical foundations serve AI answers. Our answer engine optimization page covers the strategy; the free AI crawler access checker tests access.

SEO for developers: what to check in code review

Most search damage arrives through ordinary releases, so the cheapest protection is a short list in the review process. Removed routes should return a redirect or a proper 404, and a noindex tag from staging must never reach production. Titles, canonicals and main content should be present in the first HTML response, internal links should be real anchors with an href, and structured data should still validate after a template change.

Then automate it. A build step that fetches key templates and fails on a stray noindex or a missing canonical catches the mistake before anyone has to find it in Search Console weeks later.

What a technical SEO agency delivers

1. Audit with prioritized findings and fixes.
2. Tickets with acceptance criteria, or implementation where access allows.
3. Verification of each fix by re-crawl and Search Console.
4. Monitoring for regressions after releases.
5. Migration protection when the site changes.
6. Reporting: indexing, crawl efficiency, speed, rankings and traffic.

How to choose a technical SEO agency or consultant

• Ask whether they implement fixes or only list them.
• Ask how fixes are verified after deployment.
• Ask for experience with your platform or framework.
• Ask how they use log files and Search Console, not just a crawler.
• Ask who owns the audit and the code. You must.

What it costs: technical SEO

SEO is sold as a retainer sized to the market you compete in. For technical SEO, the tiers below are the price bands from our marketing agency pricing guide and our SEO engagement models; the right tier follows an audit of the site and the competition, and the quote follows that.

Every figure above is a price band already published on this site; the quote for technical SEO follows a written scope, and the same ranges apply across the United States and worldwide.

Related services and guides

Pages on this site that sit next to technical SEO and that a buyer usually reads alongside it.

• SEO audit service
• Website speed optimization service
• International SEO agency
• Ecommerce SEO services
• Enterprise SEO agency
• Website migration services
• Tech SEO agency
• SEO for directory websites
• Publisher SEO
• Best SEO Chrome extensions

Frequently asked questions