EVE Online is moving 2.4 million lines of Python off a version that died in 2020
EVE Online is being moved off Python 2.7, sixteen years after it last changed language version and six years after that version reached end of life. The studio's own devblog puts real numbers on the job, which is the reason it is worth reading rather than skipping as housekeeping.
A note on the name, because it changed this year. The devblog credits Fenris Creations with EVE's Stackless Python work, and the studio's own announcement of 6 May 2026 is where that name comes from: the company behind EVE, formerly CCP, returned to independent ownership and renamed itself that day. We use the name the sources use.
The measured size of the problem
| Measure | Number |
|---|---|
| Lines of Python in the codebase | about 2.4 million |
| Files scanned under both interpreters | about 20,000 |
| Files that already compiled under both | 95.9% on the first scan |
| Lines using syntax Python 3 rejects | about 3,300 |
| Old-style print statements | about 1,500 |
| Long number literals such as 123L | about 800 |
| Deprecated exception clauses | about 600 |
| Uses of the ancient not-equal operator | 50 |
| Lines that compile under both and behave differently | about 20,000 |
That last row is the whole project. The example given is division: in Python 2, one divided by two is zero, and in Python 3 it is 0.5. When the numbers involved are damage, currency or coordinates, each of those lines needs a person to decide, not a tool.
Our take: what it means for players
Nothing, this year, and that is exactly why we are writing about it.
A twenty-three year old world running on a dead language version is a slow-motion risk to everyone who has a character in it. Every year on Python 2 is another year of libraries falling out of reach and more of the toolchain maintained in-house instead of spent on the game. Doing the migration is unglamorous, expensive and invisible when it works, which is why studios put it off until something breaks. Starting it before something breaks is the correct call and deserves saying out loud.
The measurement discipline is the part worth copying. Compiling every file under both interpreters to find out how far the codebase actually is, rather than estimating, turned an unbounded fear into a countable list: 3,300 lines to fix mechanically and 20,000 to read. A studio that publishes those numbers is a studio that can be held to them.
Credit belongs to the players here as well as the engineers. The first stage was tested on the public test server in late July by capsuleers who volunteered to play a version of the game whose whole ambition was to feel identical, and the studio names that testing as the reason the changes went live. That is unpaid work protecting everyone else's assets, and it is worth naming.
The honest caveat is that stage one was the easy part by the studio's own account, and no completion date is given for the rest.
What's next
More Singularity test rounds, with no dates announced, and the agent mission backend being prepared next. Nothing here is dated, so nothing joins the calendar until the studio names a day.
Common questions
Why is EVE Online moving to Python 3?
Python 2.7 reached end of life in 2020, so modern libraries, debuggers and profilers no longer support it. The stated benefits are faster performance from recent Python 3 releases, better tooling to find bugs sooner, and a codebase new developers can work in productively.
How much of EVE's code is affected?
About 2.4 million lines across roughly 20,000 files. On the first scan 95.9 percent of files already compiled under both versions, leaving about 3,300 blocking lines, plus roughly 20,000 lines that compile under both and behave differently.
Will players notice the Python 3 migration?
The stated goal is that they do not. The studio says stage one changes are meant to be invisible, and asks players to file bug reports if anything feels off. The first set of changes was tested on Singularity in July and has now been deployed to the live server.
Written by 0hp from the publisher's own announcement, linked above, and every specific in it was checked against that page by a second pass before it published. Independent, and not affiliated with the publisher. Dates are announced or labelled as estimates. How this site is written, and how to correct it.
