Every founder building a software product faces the same decision at some point: hire engineers full-time, or work with a development agency?
Both choices are valid. Both are wrong in specific situations. The decision that goes badly is usually the one made based on incomplete cost data — looking at the agency invoice and comparing it to a salary, without accounting for everything else the salary requires.
Here's the full picture.
The True Cost of an In-House Engineer
A senior software engineer in a major US tech market earns $160,000–$200,000 in base salary. That's the number founders anchor on. It's not the total cost.
Employer taxes and benefits: Add 20–30% to the base salary. Employer payroll taxes (Social Security, Medicare, FUTA), health insurance (typically $600–$1,500/month for comprehensive family coverage), 401(k) matching, equity grants, and paid leave collectively push the total compensation cost to $200,000–$260,000/year for a $175,000 base.
Recruiting: Filling a senior engineering role through a recruiter costs 15–25% of first-year salary — $25,000–$45,000 per hire. Internal recruiting time and manager interview hours add another $10,000–$20,000 in real cost. Expect to spend $35,000–$65,000 getting a senior engineer in the seat.
Ramp time: A new engineer is not productive on day one. Depending on codebase complexity, tooling, and onboarding quality, expect 4–12 weeks before a new hire is shipping meaningfully. At a fully-loaded cost of $5,000–$7,000/week, that's $20,000–$84,000 in compensation before the engineer contributes independently.
Management overhead: Engineers require management. A senior engineer without effective management produces inconsistently and may build in the wrong direction. If you're a non-technical founder, add the cost of a technical lead or VP of Engineering who can manage the team — another $200,000–$280,000/year fully loaded.
Attrition: Senior engineers at startups turn over, on average, every 18–24 months. Each turnover event costs one recruiting cycle plus one ramp period — $55,000–$150,000 depending on seniority. A 3-person engineering team over two years can expect 1–2 turnover events.
Full-stack cost for a 3-person team, Year 1:
| Line item | Cost | | --------------------------------------- | --------------- | | Salaries (3 × $175k base) | $525,000 | | Taxes and benefits (25%) | $131,250 | | Recruiting (3 × $40k avg) | $120,000 | | Ramp cost (3 × 8 weeks avg) | $100,000 | | Management overhead (partial CTO or EM) | $120,000 | | Tooling, hardware, infrastructure | $30,000 | | Total Year 1 | ~$1,026,250 |
That is the actual cost of a 3-person senior engineering team in Year 1. Not $525,000.
The True Cost of a Development Agency
A good product engineering agency charges $15,000–$40,000 for an MVP sprint and $20,000–$60,000/month for ongoing product development with a dedicated team.
What you get: Senior engineers, a designer, and a PM, working on your product full-time during the engagement. No recruiting cost, no ramp period, no benefits overhead, no management overhead (the agency manages the team).
What you don't get: Institutional knowledge that accumulates over time in an in-house team. Deep familiarity with your codebase that compounds over years. Engineers who are thinking about your product at 2am because they believe in the mission.
Full cost for 12 months of product development with an agency:
| Line item | Cost | | ------------------------------------------- | --------------------- | | Ongoing product team ($20k–$40k/month × 12) | $240,000–$480,000 | | Discovery and onboarding (one-time) | $10,000–$20,000 | | Total Year 1 | $250,000–$500,000 |
The agency is typically cheaper in Year 1, especially when accounting for all the in-house costs that don't appear in salary comparisons.
Year 2 and beyond is where in-house can become cheaper — if you retain engineers (avoiding recruiting costs), if attrition is low, and if the product is stable enough that the team is productive rather than constantly refactoring previous decisions.
When an Agency Wins
You need to move fast. Agency teams are productive from week one. There's no recruiting, no ramp, no 3-month wait to ship. We kick off on Monday and ship a working demo on Friday. That timeline is not possible with a new in-house hire.
You have a defined scope. An agency is most cost-effective when the product is scoped — you know what you're building, the core workflows are defined, and the engineering is largely an execution problem. Fixed-scope, fixed-price engagements remove billing risk entirely.
You're a non-technical founder. Building an in-house engineering team without technical leadership is one of the hardest things a non-technical founder can do. An agency comes with technical leadership built in. You get a senior engineer or tech lead managing the quality of the work, not a junior team with no oversight.
You need specialized skills temporarily. AI/ML engineering, iOS native development, IoT firmware — these are skills with limited talent pools and high salaries. An agency that maintains these capabilities across many clients can deploy them to your project without you hiring a full-time specialist for a capability you need for one quarter.
You're pre-Series A. Burning your runway on permanent headcount before you've validated the product is a strategic risk. An agency lets you ship, validate, and scale the team only after you've proved the business.
When In-House Wins
Your product is your competitive moat. If your product is deeply proprietary and requires years of institutional knowledge — deep AI models trained on your data, complex domain logic that takes months to understand, tight feedback loops with your engineering culture — in-house builds this more effectively over time.
You have strong technical leadership. A CTO who can recruit, manage, and retain senior engineers changes the math significantly. In-house teams with strong technical leadership outperform agency engagements over a 3–5 year horizon.
Your product roadmap is inherently unpredictable. Fixed-scope agencies perform best when scope is defined. If your product requires constant strategic pivots, in-house engineers who are deeply invested in the mission can adapt faster than engagements that need to be re-scoped.
You're at Series B or beyond. At scale, in-house is usually cheaper per unit of output, and the institutional knowledge differential matters more as the system grows in complexity.
The Hybrid Model Most Teams Actually Use
The most common pattern for high-growth startups: use an agency to build V1 (or to supplement the team during a crunch), hire in-house engineers as the product validates and funding arrives, and transition the codebase to the in-house team.
This requires a good agency that codes with handover in mind — documentation, sensible architecture, no vendor-specific lock-in, clean code that a new in-house engineer can read in day one. A good agency treats handover as part of the engagement, not an afterthought.
The failure mode is agencies that write code only they can maintain. Always ask: "How would we transition this codebase to our own team?" before signing. Any agency that avoids the question is answering it.
The Decision Framework
Four questions determine which option is right at your current stage:
1. How much runway do you have? Under 12 months: agency. Over 24 months with strong conviction in the product: in-house can make sense, if you can recruit.
2. Is the product scope defined or still being discovered? Defined scope → agency wins on cost and speed. Undefined scope → in-house may be more flexible.
3. Do you have technical leadership? Without a CTO or senior technical lead, building an in-house team is high-risk. An agency reduces that risk.
4. What's the product complexity over 3 years? A simple SaaS product can be run by a small in-house team. A platform with AI, IoT, mobile, and complex infrastructure needs senior specialists in each domain — which is more expensive to staff permanently than to source through an agency.
Who We Work With
We work best with founders who have a defined product, a specific outcome they're funding toward, and a preference for a fixed-price engagement over open-ended T&M billing.
Our MVP development practice takes pre-revenue founders from idea to production in 2–6 weeks. Our web app development and mobile app development teams handle ongoing product development for post-launch companies with product-market fit who need to scale the product without scaling the headcount.
We also do staff augmentation — embedding a senior engineer or designer into your in-house team, using your tools, attending your standups, shipping on your roadmap.
Book a 30-min discovery call — a product engineer joins the call (not a BDR), we scope the work, and you get a written proposal within 24 hours.