Forward Deploy · Outcome-Based

The arch is real.

The keystone

is missing.

The arch is real.

The keystone

is missing.

We embed. We don't advise.

One senior engineer in your operation. Running AI tools that do the output of a team of six. No hiring. No transformation programme. No slide deck at the end.

Start with the audit

How it works

0%

of mid-market AI pilots never reach production

of mid-market AI pilots never reach production


of mid-market AI pilots never reach production

McKinsey Global Survey, 2024

McKinsey Global Survey, 2024

$0.0M

average cost of a single data breach in 2024

average cost of a single data breach in 2024


average cost of a single data breach in 2024

IBM Cost of Data Breach Report, 2024

IBM Cost of Data Breach Report, 2024

1:6

1:6

one Keystone engineer outperforms a traditional QA team of six

one Keystone engineer outperforms a traditional QA team of six

one Keystone engineer outperforms a traditional QA team of six

Framework benchmark · representative

Framework benchmark · representative

0wk

typical time from audit to first agent in production

typical time from

audit to first agent

in production


typical time from audit to first agent in production

Representative engagement model

Representative engagement model

The forward deploy motion

Senior engineers in your operation.
Not partners on a slide.

Senior engineers in your operation.
Not partners on a slide.

Keystone does not send a team. It sends one senior engineer running an AI framework — scanning your codebase exhaustively, finding what six people used to find, writing the fixes, raising the PRs.

The sophistication of the full suite is why the buyer stays. The concreteness of one engineer outperforming your QA team is why they start.

What your engineer does from week one

What your engineer does from week one

1

Exhaustive codebase scan

AI reviews every line at speed no human team can match. Findings logged in real time.

2

Bug identification and fix

Critical issues found, fixes written, PRs raised. Your team reviews and merges.

3

Architecture and security review

Running CTO, CISO, and architect-level analysis in parallel — not five hires.

4

Agent builds and automation

Recurring tasks identified, agents specced and shipped. Maintained as models drift.

5

Audit-ready documentation

Every finding documented to compliance standards. SOC 2, HIPAA-mappable output.

THE PROBLEM

Most companies bolted AI

onto a 2019 workflow.

Most companies bolted AI onto a 2019 workflow.

Most companies bolted AI onto a 2019 workflow.

Most mid-market companies have invested in AI tools, run pilots, and hired engineers who understand the technology.

None of it has moved the numbers.

The reason is structural. The tools are real. The engineers are capable. What is missing is the piece that makes it all hold — the human judgment layer that decides where AI plugs in, what it touches, and what happens when it's wrong.

The arch is built from both sides. The keystone has not been placed. The scaffolding is still doing the work.

Team replacement

One engineer. The output of six.

One engineer. The output of six.

One engineer.

The output of six.

At the entry level we compete with your QA team. One Keystone engineer outperforms a traditional team of six — at a fraction of the cost, with higher coverage and faster turnaround.

Traditional model

A QA team built the old way

$0.000

/yr

7 US engineers — fully loaded

3–6 month hiring cycle before output

3–6 month hiring cycle before output

Limited to human review speed

Limited to human review speed

Partial codebase coverage

Partial codebase coverage

One discipline per person

One discipline per person

No architecture or security depth

No architecture or security depth

VS

VS

The Keystone model

One engineer. AI-amplified.

from $0.000

/mo

Outcome-priced. Deployed in days.

Operational from day one — no hiring cycle

Operational from day one — no hiring cycle

Exhaustive codebase coverage at AI speed

Exhaustive codebase coverage at AI speed

CTO, CISO, Architect, QA, Tester — one person

CTO, CISO, Architect, QA, Tester — one person

Finds bugs, writes fix, raises PR

Finds bugs, writes fix, raises PR

Grows into full AI architecture function

Grows into full AI architecture function

What we offer

Four ways in. All outcome-priced.

Four ways in.

All outcome-priced.

No hourly rates. No day rates. We price against what we find and what we fix. The audit fee converts to credit if you proceed.

01

Entry point

AI Readiness Audit

AI Readiness Audit


2–4 weeks. We read your code, workflows, and operations. We find where AI has been introduced without the structure changing. You get a prioritised roadmap, not a slide deck.

2–4 weeks. We read your code, workflows, and operations. We find where AI has been introduced without the structure changing. You get a prioritised roadmap, not a slide deck.


$15,000 – $35,000

$15,000 – $35,000

fixed fee

02

Lead wedge

Vulnerability +

Architecture Scan

Vulnerability +

Architecture Scan

Five personas reviewing your codebase in parallel. Every finding priced to fix before you commit. Audit-ready output. Pre-approved severity tiers — no surprise invoices.

Five personas reviewing your codebase in parallel. Every finding priced to fix before you commit. Audit-ready output. Pre-approved severity tiers — no surprise invoices.


$3,000 – $20,000

$3,000 – $20,000

per issue resolved

03

Output-based

Agent Build

Agent Build


We identify recurring tasks that cost you real money but aren't worth a full hire. We spec it, build it, ship it with monitoring. Priced against what it recovers — not how long it took.

We identify recurring tasks that cost you real money but aren't worth a full hire. We spec it, build it, ship it with monitoring. Priced against what it recovers — not how long it took.



$15,000 – $40,000

$15,000 – $40,000

per agent shipped

04

Long-tail revenue

Forward Deploy Pod

Forward

Deploy Pod

A senior engineer embedded as your fractional AI architect. Running the full framework. Maintaining agents as models drift and regulations evolve. This is where the long-term leverage lives.

A senior engineer embedded as your fractional AI architect. Running the full framework. Maintaining agents as models drift and regulations evolve. This is where the long-term leverage lives.

$25,000 – $40,000

$25,000 – $40,000

MONTHLY

One engineer. Five virtual experts.

What the framework runs in parallel.

When your Keystone engineer runs the framework, five senior personas work simultaneously at AI speed —

not five separate hires, not five separate invoices. One person with the tools to simulate all of them.

When your Keystone engineer runs the framework, five senior personas work simultaneously at AI speed — not five separate hires, not five separate invoices.

One person with the tools to simulate all of them.

CTO

$400–600k/yr to hire

Architecture review, tech debt assessment, rebuild roadmap, infrastructure strategy

Architecture review, tech debt assessment, rebuild roadmap, infrastructure strategy

CISO

$350–500k/yr to hire

Vulnerability identification, security posture, compliance mapping, threat surface

Vulnerability identification, security posture, compliance mapping, threat surface

Architect

$250–380k/yr to hire

System design, scalability, modern pattern benchmarking, dependency review

System design, scalability, modern pattern benchmarking, dependency review

Quality Lead

$180–260k/yr to hire

Test coverage, regression risk, code quality standards, release confidence

Test coverage, regression risk, code quality standards, release confidence

White-Box Tester

$160–240k/yr to hire

Deep code path, race conditions, threading bugs, edge cases, exploit simulation

Deep code path, race conditions, threading bugs, edge cases, exploit simulation

Combined annual cost to hire all five in-house

$0.0M

$0.0M

/ year

Continuous review from $20k/month

Continuous review from $20k/month

Combined annual cost to hire

all five in-house

$0.0M

$0.0M

/ year

Continuous review from $20k/month

Annual cost to deliver the same outcome

What you pay elsewhere vs here.

What you pay elsewhere vs here.

The cost of senior engineering oversight has not changed. What has changed is how much of it needs to be human.

McKinsey / Big 4 transformation

McKinsey / Big 4 transformation

$800k – $2M

Per engagement

6–18 months

Per engagement

6–18 months

Per engagement

6–18 months

In-house senior team (US)

In-house senior team (US)

$600k – $900k

Annual

4–6 people fully loaded

Annual

4–6 people fully loaded

Annual

4–6 people fully loaded

Fractional CTO + QA lead only

Fractional CTO + QA lead only

$180k – $300k

Annual

limited scope, no agents

Annual

limited scope, no agents

Annual

limited scope, no agents

Keystone

Keystone

$240k – $480k

Annual

full suite + agents

Annual

full suite + agents

Annual

full suite + agents

Time to value

Months to hire. Days to deploy.

Months to hire.

Days to deploy.

Traditional hiring approach

1

Week 1-6

Job specs and sourcing

Define roles, brief recruiters, build pipeline for 5–6 positions simultaneously

2

Weeks 6–14

Interviews and offers

Panel interviews, technical assessments, offer negotiations, counteroffers

Panel interviews, technical assessments, offer negotiations, counteroffers

3

Weeks 14–24

Notice periods and onboarding

4–12 week notice periods, access provisioning, team integration, ramp-up

4

Month 6+

First meaningful output

Team aligned, tools set up, processes established. First real findings delivered.

KEYSTONE

1

Day 1–3

Scoping call + codebase access

Scope confirmed, engineer assigned and briefed, framework deployed. No hiring.

2

Week 1–2

Full scan begins immediately

Five virtual personas running in parallel. Findings logged and prioritised in real time.

3

Week 2–4

Diagnostic report delivered

Full findings with severity tiers, cost estimates per issue, and fix roadmap.

4

Week 4–6

First agents in production

Critical fixes shipped. First agents deployed. Audit-ready documentation in hand.

5

Week 6

First fixes merged, audit-ready documentation in hand

Return on investment — worked example

What a $40M company typically finds.

A representative engagement across mid-market software businesses at the $30M–$60M revenue range.

What Keystone costs — year one

What Keystone costs — year one

What Keystone costs —

year one

AI Readiness Audit

$20,000

Critical vulnerability resolution ×4

Critical vulnerability resolution ×4

Critical vulnerability

resolution ×4

$40,000

Agent builds ×3 workflows

Agent builds

×3 workflows

$75,000

Forward deploy pod (6 months)

Forward deploy pod

(6 months)

Forward deploy

pod (6 months)

$150,000

Total year-one investment

Total year-one

investment

$0.000

What it recovers

Redundant labour recovered

$420k

3 workflows automated across ops and QA

3 workflows automated across ops and QA

3 workflows automated across

ops and QA

Breach risk reduction value

$900k

4 critical vulnerabilities resolved pre-incident

4 critical vulnerabilities resolved pre-incident

4 critical vulnerabilities resolved

pre-incident

Engineering velocity gain

$280k

Reduced rework, faster releases

Reduced rework, faster releases

Total recovered value

$0.0M

5.6× return on year-one investment

What a typical scan finds

Most codebases carry more risk than they know.

Most codebases carry more risk

than they know.

Most codebases carry more risk than they know.

A Keystone scan of a mid-market SaaS codebase (250k–1M lines) typically surfaces findings across four severity tiers within two weeks.

Typical findings — mid-market SaaS audit

Typical findings — mid-market SaaS audit

Typical findings — mid-market SaaS audit

Critical

Critical

3–5 issues
3–5 issues

$10–50k ea

$10–50k ea

High

High

8–14 issues
8–14 issues

$5–20k ea

$5–20k ea

Medium

20-35 issues
20-35 issues

$3–8k ea

$3–8k ea

Low

40-80 issues
40-80 issues

$1–3k ea

$1–3k ea

All findings come with severity assessment, cost to fix, and prioritised resolution order. Tier pricing approved upfront — no surprise invoices.

What critical findings look like in practice

What critical findings look like in practice

What critical findings look like in practice

Multi-threading collision in shared cache

Multi-threading collision in shared cache

Multi-threading collision in

shared cache

Cache accessed simultaneously by multiple threads — causes intermittent data corruption under load. Found in a single scan today on a real production system.

Authentication bypass via header injection

Authentication bypass via header injection

Authentication bypass via

header injection

Improperly validated headers allow privilege escalation. Invisible in normal testing, exploited by automated scanners in hours.

Unbounded memory growth in event loop

Unbounded memory growth in event loop

Unbounded memory growth

in event loop

Event listeners never deregistered — causes gradual memory leak that crashes production under sustained load.

API key exposed in version-controlled config

API key exposed in version-controlled config

API key exposed in

version-controlled config

Production credentials in repository history. Accessible to anyone with repo access, including former employees.

The objection

You could run Claude yourself.

You could run Claude yourself.

For a weekend code review, you should. For a production system thousands of people depend on, the distance between "an LLM can look at this" and "an LLM can systematically protect this" is where companies lose millions.

01

Your codebase does not fit in the window.

Your codebase does not fit in the window.

Even the largest context windows hold 1–2M tokens — a production system runs 12–80M. You review a fragment, and most bugs hide in the interactions between files that were never in context together.

Even the largest context windows hold 1–2M tokens — a production system runs 12–80M. You review a fragment, and most bugs hide in the interactions between files that were never in context together.

1–2M of a 12–80M-token system — under 10% in any one session

1–2M of a 12–80M-token system — under 10% in any one session

02

LLMs are confidently wrong. Regularly.

LLMs are confidently wrong. Regularly.

The dangerous output is not the obvious error — it is the plausible answer your team ships without questioning. Catching it takes an expert who knows which question to ask and can tell when the answer is wrong.

The dangerous output is not the obvious error — it is the plausible answer your team ships without questioning. Catching it takes an expert who knows which question to ask and can tell when the answer is wrong.

~30% false-positive rate without expert validation

~30% false-positive rate without expert validation

03

A chat answer is not a merged fix.

A chat answer is not a merged fix.


A suggestion is the start, not the end. Someone validates it, implements it, reviews it, ships it. Keystone's framework writes the fix, the engineer validates it, and the PR is raised against a branch for your team to merge.

A suggestion is the start, not the end. Someone validates it, implements it, reviews it, ships it. Keystone's framework writes the fix, the engineer validates it, and the PR is raised against a branch for your team to merge.

0 PRs — a chat produces text, not shipped code

0 PRs — a chat produces text, not shipped code

04

Pasting code into a commercial LLM is a risk.

Pasting code into a commercial LLM is a risk.

Without a data-processing agreement, your source — your most valuable asset — enters a third-party model. For SOC 2, HIPAA or GDPR that is a compliance event, and a chat export is not evidence an auditor will accept.

Without a data-processing agreement, your source — your most valuable asset — enters a third-party model. For SOC 2, HIPAA or GDPR that is a compliance event, and a chat export is not evidence an auditor will accept.

Keystone runs under a DPA — code stays controlled

Keystone runs under a DPA — code stays controlled

The AI does the scanning. The human does the judgment.

That is the difference between a conversation and a system that holds in production.

The AI does the scanning. The human does the judgment.

That is the difference between a conversation and a system that holds in production.

$0-
0k/mo

Keystone — all-in

VS

$4.5M+

One missed vulnerability at scale

The AI does the scanning. The human does the judgment. That is the difference between a conversation and a system that holds in production.

$0-
0k/mo

Keystone — all-in

VS

$4.5M+

One missed vulnerability

at scale

Market validation

The model is being validated
at the highest level.

The model is being validated at the highest level.

Building defensibility in the software layer on top of the models is going to be incredibly difficult. It is the ability to layer services on top of software — going the last mile with the customer, the forward deployed motion — that is creating stronger defensibility.

Mercor · $10B valuation · $1B+ revenue · 2025

Mercor

$10B valuation

$1B+ revenue, 2025

Start with the audit.
Risk nothing.

Start with

the audit.
Risk nothing.

The audit fee converts to credit if you proceed. If the findings don't justify the next step, you walk away with a roadmap worth more than you paid for it.

Book a 30-minute call

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