Interim CTO for the months between CTOs
An interim CTO covers the role for a defined period – after a CTO leaves, through an acquisition, or while you search for the permanent hire. The job is narrow and urgent: keep the system and the team stable, keep shipping, and set up the next CTO to succeed.
I’ve been the CTO through an acquisition and I’ve co-founded and sold a software studio, so I know what the gap feels like from both sides. I start with a two-week sprint, and the goal from day one is to leave.
The three gaps an interim CTO covers
- A departure. The CTO or founding engineer has left, sometimes on short notice. Knowledge walked out with them, the team is unsettled, and the board wants to know whether the roadmap still holds.
- An acquisition or merger. Someone has to answer the acquirer’s technical questions, plan the integration, and keep engineers from quietly updating their CVs while it happens.
- A pre-hire gap. You know you need a permanent CTO, but the search will take three to six months and you can’t write a convincing job spec yet because nobody has looked hard at what the role needs.
These look different but the first month is similar in all three: find out what you actually own, stop anything that’s about to break, and make sure the team knows who’s making decisions.
The first two weeks: control before strategy
A CTO departure exposes things that were held in one person’s head or one person’s password manager. Before I form any opinion about architecture, I work through a short list:
- Access and ownership. Who holds the root account on AWS or GCP, the domain registrar, DNS, the app store developer accounts, the Stripe account, the GitHub organization? Accounts registered to a personal email address get moved to company ownership first.
- Can we deploy without them? I build and ship from a clean machine using only what’s written down. Where that fails, the gap becomes the first piece of documentation.
- Do the backups restore? Not “are backups configured” – an actual restore into a scratch environment, timed.
- What’s on fire? Error rates, open incidents, unpaid vendor invoices, certificates and API keys close to expiry, contracts with renewal dates.
- One shipped change. Something real goes to production in the first fortnight, through the normal process, so the team sees that delivery continues.
At the end of the sprint you get a short written view: what’s at risk, what I’d do next, and what the permanent CTO role should look like.
Keeping the team and the roadmap moving
Teams don’t stall in a CTO gap because they lack skill. They stall because nobody will make a call on the decisions that were waiting for the old CTO – the database migration, the vendor contract, the senior hire. I make those calls, write down the reasoning, and keep the list short.
I also work in the code. Reviewing pull requests and pairing on the hardest change of the sprint is the fastest way I know to understand a system, and it tells the team that the interim leader isn’t just there to hold meetings.
For the roadmap, I don’t rewrite strategy in month one. I cut the roadmap down to what the current team can deliver and make the trade-offs visible to the founders and board. A technical roadmap rewrite, if it’s needed, is better owned by the permanent hire.
Interim CTO during an acquisition
If you’re selling, the interim CTO prepares the data room’s technical side and answers diligence questions accurately – the technical due diligence checklist is roughly what the buyer’s team will work through. If you’re buying, the interim role is about integration: identity, billing, data, and which of two overlapping systems survives.
In both cases the people risk is bigger than the code risk. Engineers want to know whether their work still matters. Clear, honest communication about what changes and what doesn’t keeps the people you need through the close.
Hiring the permanent CTO
An interim engagement should end with a hire, and I help run it: a job spec based on what I’ve learned about your system and team, a CTO job description that reflects the actual work, an interview loop with a practical technical component, and a handover plan.
Sometimes the right permanent hire isn’t a CTO at all. A ten-person team with a clear architecture may need a strong VP or head of engineering, with the founders keeping product ownership. I’ll say so if that’s what I see.
When you don’t need an interim CTO
If a senior engineer on the team is ready to step up and just needs backup, you’re better served by an hour or two of coaching a week than by bringing in an outsider. And if the gap is long-term rather than temporary – you don’t expect to hire a full-time CTO in the next year – look at fractional CTO work instead, which is designed to run indefinitely.
Questions
How long does an interim CTO engagement last?
Usually as long as the gap: through the close of an acquisition, or until the permanent CTO starts and has had a few weeks of overlap. It starts with a two-week sprint, and you can stop at any point after that with no notice period.
What’s the difference between an interim CTO and a fractional CTO?
An interim CTO fills a temporary vacancy and plans the handover from the start. A fractional CTO is an ongoing part-time arrangement for companies that don’t yet need a full-time CTO. The day-to-day work overlaps; the exit plan is what differs.
Can the interim CTO become the permanent CTO?
Not with me. I work with a small number of clients for a fixed number of days a week, not as a full-time hire. That’s useful in an interim role: I have no stake in the search outcome, so I can help you hire the best candidate.
Do interim CTO services include hands-on engineering?
With me, yes. I review pull requests, pair on hard changes and ship code, though not on the critical path. It keeps my judgement tied to your real codebase rather than to what people tell me about it.
Does a startup CTO gap need an interim CTO?
Not always. If the startup has two or three engineers and one is ready to lead, coaching them is cheaper and builds the team. An interim CTO makes sense when nobody can own the decisions, or when investors and an acquirer need a credible technical counterpart.
Your CTO just left, or is about to?
Tell me what the gap looks like. We start with a two-week sprint to secure access, keep shipping and map what the next CTO inherits.
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