---
title: "Will Forward Deployed Engineers Replace CSMs? What Each Owns"
description: "Forward deployed engineers take the technical implementation slice at AI-native and enterprise firms. The CSM role narrows to outcomes, renewals and expansion."
topic: "Customer Success"
author: "Raj Bheda, Co-founder, GainTrace"
audience: "Customer Success Manager, VP Customer Success"
published: 2026-09-04
modified: 2026-09-04
source: https://gaintrace.com/explore/customer-success/will-forward-deployed-engineers-replace-customer-success-managers
---

# Will Forward Deployed Engineers (FDEs) Take Customer Success Manager (CSM) Jobs?

*An opinion, argued from 946 r/CustomerSuccess threads*

**Short answer:** Forward deployed engineers (FDEs) will not take customer success manager (CSM) jobs. They take one slice of the work: the technical implementation at AI-native and enterprise companies where the product must be built to fit each customer. That slice used to belong to generalist CSMs. What remains for the CSM narrows toward outcomes, renewals and expansion, and that narrower role is the one companies keep paying for.

**Key takeaways**

- An FDE is hired to make the product work inside one customer's environment and is measured on time to live. A CSM is hired to keep a book of customers renewing and expanding and is measured on retention. Different job, different clock.
- FDEs only pencil where the deal can carry an engineer's cost for the deployment period, which means AI-native products and enterprise contracts. Most B2B SaaS books are not that.
- The CSM job at risk is the generalist one: logging, reporting, check-ins and relaying tickets. The Reddit thread that started this debate says so itself, and its author is a CS leader.
- Pick a lane inside 12 months: technical (scope deployments with engineers) or commercial (carry a renewal and expansion number). The CSM who does neither is the one an FDE plus an AI agent replaces.
- If you are hiring, the decision rule is whether every new customer needs engineering to go live. If yes, hire the FDE first and name the day the account hands to a CSM.

Forward deployed engineers (FDEs) have started showing up in your feed as the new customer success managers (CSMs), and it landed while your own company is talking about agentic workflows and asking what a CSM is for. One thread on r/CustomerSuccess put the question to a CS leader and got 21 comments. Another, from a CSM with eight years in the job, asked whether an FDE is a role a technical CSM can move into or something only an engineer can do. You are asking the same two things: is my job going away, and if part of it is, which part.
Our position is that the FDE takes a slice, at a specific kind of company, and that the slice is one most CSMs were never good at anyway. This page argues that from the threads and from what 3,628 public G2 reviews say CSMs spend their time on, gives the counter-argument its fair hearing, and ends with what to do in the next 12 months whether you are a CSM or the person deciding which role to hire.

## What do forward deployed engineers do, and where?

An FDE is a software engineer who sits with the customer, often on site, and builds whatever the product needs to work in that customer's environment: the integrations, the data pipelines, the configuration, and at AI companies the prompt, retrieval and evaluation work that turns a general model into something that answers this customer's questions from this customer's data. The role is old. Enterprise software has always sent engineers to implement, and the thread that started the debate says exactly that.

> "B2B software companies have always had FDE's involved in implementation. They guided the customer through the whole process; integration, training, and onto go-live."
>
> — CS leader, r/CustomerSuccess, 2026

What is new is where the role sits. At AI-native companies the product frequently does not work out of the box for anyone; each customer needs weeks of engineering before the value exists, so the FDE is the first person the customer meets after the contract, and the person the customer trusts. That is the origin of the "FDEs are the new CSMs" idea: at those companies, the post-sale relationship starts with an engineer.

The scale of the conversation is worth knowing. Of the 946 r/CustomerSuccess threads we collected, 220 mention AI in the title or body. Five mention forward deployed engineers or FDEs. The FDE question is real, and it is a small corner of a much larger anxiety about the role, which we take up separately in [will AI replace customer success managers](https://gaintrace.com/explore/customer-success/will-ai-replace-customer-success-managers).

## Forward deployed engineer (FDE) or customer success manager (CSM): what does each own?

Put the two roles side by side and the overlap is narrower than the debate suggests. The table is our reading of the threads, of the job descriptions companies publish for each role, and of what the G2 corpus says CSMs are asked to do.

|  | Forward deployed engineer (FDE) | Customer success manager (CSM) |
| --- | --- | --- |
| What they own | Making the product work inside one customer's environment: integrations, data pipelines, configuration, custom code, and at AI companies the tuning that makes the model useful on this customer's data. | The outcome and the commercial relationship across the contract: adoption against the customer's goals, renewal, expansion, executive alignment, and risk across a book of accounts. |
| When they are hired | When most new customers need engineering to go live: AI-native products, enterprise deals with bespoke integrations, early products that are half consulting. Usually attached to a deal or a handful of accounts. | When there are enough customers on a repeatable product that someone must own retention across a book, and the account count justifies a ratio. |
| How they are measured | Time to live, technical milestones shipped, whether the deployment works, and sometimes the margin on the deployment. | Gross and net revenue retention, renewals on time, expansion sourced, and the health of the book. See [net revenue retention](/explore/revenue/how-to-calculate-net-revenue-retention-b2b-saas). |
| Time horizon | Weeks to months, front-loaded at deployment, then gone or on call. | The whole contract term, renewal to renewal, for years. |
| Who they report to | Engineering, a forward deployed group, or sales engineering. | Customer success, increasingly the revenue organisation. |
| What the deal must carry | An engineer's cost for the deployment period, which only works on high-contract-value deals. | A fraction of one person per account, spread across the book. The maths is in [the coverage model](/explore/playbooks/accounts-per-csm-coverage-model). |

The last row decides most of it. An FDE costs what an engineer costs, so the contract has to be large enough to pay for one for the weeks or months of deployment. A mid-market SaaS product with a five-figure average contract cannot put an engineer on every account. It can put one CSM across dozens of them.

## Where do the two roles overlap, and who wins the overlap?

> **The build-or-adopt split:** The build-or-adopt split: forward deployed engineers own the accounts where the customer needs something built, customer success managers own the accounts where the customer needs something adopted. Both roles show up in the same deals, and the overlap goes to whoever owns the outcome the customer is paying for.

The overlap is the first 90 days. Both roles are in the account during onboarding, both talk to the champion weekly, both carry product feedback back to the company, and both are asked "can it do this" by the customer. In that window the FDE usually wins, because the customer's question is technical and the FDE can answer it by changing the product. A CSM who can only relay the question to someone else is visibly the less useful person on the call.

After go-live the overlap ends and the FDE leaves. Somebody has to own the account for the remaining nine months of the contract: notice that the champion changed jobs, that usage narrowed to one team, that the renewal is in 90 days and nobody has raised a purchase order. None of that is engineering work. The CS leader who wrote the thread was blunt about what makes the difference.

> "There will always be a need for people who have in-depth knowledge of the product *and* the customers' business. The difference between FDE's and trusted advisor CSMs is, and will be, in how a company uses them to ensure retention and expansion of the company-customer relationship. Both are needed."
>
> — CS leader, r/CustomerSuccess, 2026

So the honest split is: the FDE owns the technical outcome at deployment, the CSM owns the business outcome across the term, and the handoff between them is the point most companies never write down. The CSM who tries to hold the technical work loses it to the FDE. The FDE who tries to hold the renewal is doing a second job badly, at an engineer's salary.

## Why does the customer success manager (CSM) role narrow rather than disappear?

Three things sit under our position. First, the FDE work shrinks as the product matures. Everything an FDE builds twice becomes a product feature, and at that point the company stops needing an engineer per customer. The FDE headcount at a given company is a bet that the product is still unfinished; the CSM headcount is a bet that the customers will still be there next year.

Second, retention is a year-round job that nobody in engineering wants. The evidence for that is the existence of the CS function at the AI-native companies themselves. One VP of customer success at what he described as one of the larger AI-native startups wrote on the same subreddit that he leads a team of around 80 CSMs, with the top of the team earning in the region of $250,000. If FDEs replaced CSMs anywhere, it would be there, and the team is 80 people.

Third, what the FDE removes from the CSM job was already the weakest part of it. Across 3,628 public G2 reviews of the three most-reviewed customer success platforms, 734 name setup, configuration or admin as the main downside and 187 use the word "manual" about their own work. The generalist CSM job that the thread's author says is at risk from AI, the busywork of logging, reporting and relaying, is the same job that platforms have failed to remove for a decade. The threat to it is real. It is also not the FDE.

> **Our position in one line:** FDEs take the technical deployment at companies whose product needs one. AI takes the busywork everywhere. What is left is a smaller number of CSMs who own outcomes, renewals and expansion for a book, and that job is more senior and better paid than the one it replaces.

### Which CSM jobs are at risk?

- The generalist who relays: forwards tickets to support, forwards feature requests to product, forwards technical questions to an engineer, and reports on all three. Every leg of that job is being automated or absorbed by the FDE.
- The check-in CSM: monthly calls with no agenda beyond "how is everything going", QBRs read from a template. [When QBRs stop being useful](https://gaintrace.com/explore/playbooks/qbr-template-when-qbrs-stop-being-useful) describes what replaces it.
- The CSM with no number: no retention, expansion or outcome metric attached to their name. When a company reorganises, this is the person whose work cannot be shown.
- Not at risk: the CSM who can scope a deployment with an engineer, or the CSM who carries a renewal and expansion number and hits it. Both are being hired more, not less.

## What should a CSM do in the next 12 months?

The eight-year CSM who asked the second thread had already worked out the answer; he was asking for permission. His framing is the one we would use.

> "I understand the conventional belief is that for most CSMs, the future likely involves one of two paths: getting highly involved in revenue or getting more technical."
>
> — Enterprise CSM, r/CustomerSuccess, 2026

1. **Months 1 to 3: pick the lane and say it out loud.** Technical (scope integrations, sit with engineers, move toward solutions or FDE-adjacent work) or commercial (own renewals and expansion for a book). Tell your manager which one. The CSM who stays in the middle is choosing the generalist job by default.
2. **Months 1 to 3: put a number on your book.** Gross revenue retention, net revenue retention, or expansion sourced, for your accounts, reported monthly without being asked. If you have never calculated it, the [NRR calculator](https://gaintrace.com/tools/nrr-calculator) is a start. A CSM with a number survives a reorganisation; a CSM with a satisfaction score does not.
3. **Months 3 to 6: learn the deployment well enough to scope it.** Read the API documentation, sit in on every FDE or implementation call you can, and write down what each customer needed built to go live. You do not need to write the code. You need to be the person who can tell a customer what is possible and what it costs before the engineer is booked.
4. **Months 3 to 6: give the busywork to a machine.** Call logging, summaries, draft follow-ups, pre-call briefs. The 90-day plan in [will AI replace customer success managers](https://gaintrace.com/explore/customer-success/will-ai-replace-customer-success-managers) is the how. The hours you get back are the hours the next two steps need.
5. **Months 6 to 9: own one measured outcome for three accounts.** Not adoption, an outcome: hours saved, revenue recovered, a process the customer retired. Write it down with the customer, measure it, and put it in the renewal conversation. This is the work an FDE cannot do and an AI agent cannot do.
6. **Months 9 to 12: write the case for the role you want.** In numbers: the book's retention, the outcomes delivered, the deployments you scoped. If your company is going FDE-first, this is the document that makes you the CSM the FDEs hand accounts to, rather than the one whose work they absorbed.

## What is the strongest counter-argument to this?

The strongest version of the other side goes like this. At AI-native companies the post-sale relationship is technical for the whole contract, because the product keeps changing and the customer's data keeps changing with it. The person who fixes things is the person the customer trusts, and that person is the FDE. A CSM who cannot change the product is a messenger, and messengers get cut. Meanwhile, companies are folding customer success into account management outright. One CSM described the second of two layoffs in a year.

> "The second happened when the company eliminated the Customer Success function altogether and absorbed those responsibilities into Account Management."
>
> — Senior CSM, r/CustomerSuccess, 2026

Another was told his principal CSM title was being replaced with "AI Growth Strategist". And the CS leader who wrote the original thread concedes that generalist CSM jobs are at risk. Put together: the technical half goes to the FDE, the administrative half goes to an agent, and the commercial half goes to an account manager. There is no CSM left.

Here is why we still hold our position. Every example above is a narrowing, and each names where the narrowed role went: to an account manager with a number, to a growth title, to a technical role. None of them describes a company that stopped having a person accountable for whether customers renew. The title moves; the job stays. And the counter-argument only fully applies at companies whose product is unfinished enough to need an engineer per customer, which is a real category and a small one. For a mid-market SaaS company with 400 customers on a repeatable product, the FDE question is not even the right question. The right one is whether your CSMs carry a number.

## If you are hiring, do you need an FDE, a CSM, or both?

For the VP deciding which role to open next, the answer follows from the table. Run through the list; the first "yes" usually settles it.

**Hiring decision**
- [ ] Does most new customers' go-live need engineering work that is different each time? If yes, hire the FDE first. If the work is the same each time, it is a product gap, and an FDE is an expensive way to avoid fixing it.
- [ ] Can the average contract carry an engineer's cost for the deployment period? If not, the FDE role does not pencil and you need an implementation specialist and a CSM instead.
- [ ] Nine months after go-live, who is accountable for the renewal? If the answer is "the FDE" or "nobody", that is the CSM gap, whatever the product's technical depth.
- [ ] Are your current CSMs spending most of the week on logging, reporting and relaying? Fix that before hiring either role; you are about to hire around a problem that software should remove.
- [ ] If you hire both, write the handoff: the day the FDE leaves, the artefacts that transfer, and the outcome the CSM inherits as a number. The overlap is where the two roles fight.
- [ ] Whichever you hire, give them the same view of the account. An FDE who cannot see renewal risk and a CSM who cannot see deployment status will each blame the other.

If you are building the function from nothing, [building a customer success function from scratch](https://gaintrace.com/explore/customer-success/building-a-customer-success-function-from-scratch) covers the first 90 days, and [when to buy customer success software](https://gaintrace.com/explore/customer-success/when-to-buy-customer-success-software) covers the point at which the admin work above stops being a hiring question.

## How does GainTrace fit a narrower CSM role?

A CSM who owns outcomes, renewals and expansion for a book needs the account's technical state, commercial state and behaviour in one place without an admin to assemble it. GainTrace connects billing, CRM, product usage and support in the first week, so the day an FDE hands over an account the CSM inherits its history rather than a Slack thread. [Churn prediction](https://gaintrace.com/solutions/churn-prediction) ranks the book by what has changed, and [expansion intelligence](https://gaintrace.com/solutions/expansion-intelligence) shows where the commercial lane the page describes has revenue in it.

## Frequently asked questions

### What is a forward deployed engineer in customer success?

A forward deployed engineer (FDE) is a software engineer who works inside a customer's environment to make the product function there: integrations, data pipelines, configuration, custom code, and at AI companies the tuning that makes a model useful on the customer's data. The role sits in engineering, is attached to specific deals, and is measured on time to live rather than on retention.

### Will forward deployed engineers replace customer success managers?

No. They replace the technical implementation slice of the job at companies whose product needs engineering to go live, mostly AI-native products and enterprise contracts. The CSM role narrows toward outcomes, renewals and expansion across the contract term, which an FDE neither wants nor is paid for. The CSM at risk is the generalist who relays questions and logs activity; that job is being absorbed by AI, not by FDEs.

### What is the difference between a CSM and an FDE?

An FDE owns the technical outcome at deployment, over weeks or months, and reports to engineering. A CSM owns the business outcome across the whole contract, from go-live to renewal, and is measured on gross and net revenue retention. They overlap in the first 90 days, when the FDE usually leads, and the handoff at go-live is the part most companies never define.

### Can a customer success manager become a forward deployed engineer?

Sometimes, if the CSM can write code or is willing to learn to. More often the technical path for a CSM leads to a solutions, technical account management or implementation role that sits beside the FDE: scoping the deployment, knowing the API surface, telling customers what is possible before an engineer is booked. That role is being hired more, and it does not require an engineering background.

### Should a startup hire a forward deployed engineer or a customer success manager first?

Hire the FDE first if most new customers need different engineering work to go live and the contract value can carry an engineer for the deployment period. Hire the CSM first if the product is repeatable and nobody owns the renewal nine months after go-live. If your existing CSMs spend most of the week on logging and reporting, fix that with software before hiring around it.

## How this was researched

We read 1,328 Reddit threads collected on 2026-09-04, 946 of them from r/CustomerSuccess, and grepped title and body for "forward deployed" or "FDE" (5 threads), for "AI" (220 of the 946) and for "AI" paired with "replace" (15). We read the two FDE threads and the related career threads in full; quotes are verbatim with only typographic apostrophes straightened. The G2 figures (734 of 3,628 (20%) reviews naming setup or admin as the main downside; 187 using the word "manual") come from the same public review corpus as our implementation study. The role comparison table and the position are ours; no CSM on the threads is a customer of ours.

## Sources

- [r/CustomerSuccess: Are Forward Deployed Engineers the Future of Customer Success?](https://reddit.com/r/CustomerSuccess/comments/1tom61k/are_forward_deployed_engineers_the_future_of/)
- [r/CustomerSuccess: CSM vs. FDE: am I missing something?](https://reddit.com/r/CustomerSuccess/comments/1tns4ut/csm_vs_fde_am_i_missing_something/)
- [r/CustomerSuccess: AMA interest? (VP of CS at an AI-native startup leading ~80 CSMs)](https://reddit.com/r/CustomerSuccess/comments/1vt31i8/ama_interest/)
- [r/CustomerSuccess: Anyone else lose ambition as a CSM under this new job market & AI era?](https://reddit.com/r/CustomerSuccess/comments/1u17glv/anyone_else_lose_ambition_as_a_csm_under_this_new/)
- [r/CustomerSuccess: Just got told I'm being re-org'd from Principle CSM to AI Growth Strategist](https://reddit.com/r/CustomerSuccess/comments/1uco5j6/just_got_told_im_being_reorgd_from_principle_csm/)

## Next steps

Give the narrower CSM role the whole account in one view from day one, without an admin to build it. [Start free](https://app.gaintrace.com/auth/login) or [book a demo](https://gaintrace.com/booking).